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Hello!
My 240 broke down last night and wouldn't run - story below.
Over the past few weeks, the car has bogged down and hesitated on cold start. It would do this up until the engine warmed up a bit, then everything would be back to normal. This would only happen on some days - generally cold days. Yesterday, the car started behaving that way over the whole drive, even after warming up. And last night it totally gave up - sputtered out and died.
Symptoms (that I could tell - it was freezing rain last night so I couldn't do much but get a tow):
Backfiring (could hear it through the intake a few times)
If the car started, it would run at ~200-300 RPM, very jumpy, until it died a few seconds later.
Oil pressure was good. No coolant in oil, no oil in coolant.
Fuel economy gauge showed a pretty steady increase in manifold pressure until the car died each time.
Fuel pump relay is clicking normally (dropped a spare in, just in case).
Unplugging the AMM or IAC (separately) did nothing.
Distributor cap/rotor are in great shape - no moisture in there
Jumping the right side of fuse 4 to the left side of fuse 6 did nothing - no pump buzz.
Hooked up a spare ECT (just let it sit in the engine bay) - no change
That last note is probably the culprit (main fuel pump) - the pump is original (347,000 miles), but I just wanted to see if anyone had other advice. It seems like the car is running super lean. I probably forgot to add a few things - so ask questions if you've got 'em!
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Sorry to hear about your wagon problem Mike.
Art helped me out last year when my wagon was bogging down. It ended up being a bad AMM.
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Alright, so I finally spent some time testing on Saturday. Before that - a quick symptom update. The car runs great the first time I start it everyday, and hesitates/stumbles for a minute or so everytime I stop/restart. More information on that further down...
Fuel pressure (pumps running, engine not running, using vacuum pump to adjust pressure via fuel pressure regulator vacuum port):
48 psi (0 psi vacuum)
46 psi (2.5 psi vacuum)
43 psi (5 psi vacuum)
41 psi (7.5 psi vacuum)
38 psi (10 psi vacuum)
36 psi (12.5 psi vacuum)
Couldn't pull a harder vacuum with the vacuum pump after this. The specs (Bentley) said that the fuel pressure drop should be equal to the vacuum increase. My measurements seem to match that.
Just to be sure, I measured the fuel pressure with the car running:
48-49 psi (FPR vacuum line removed and plugged)
40 psi (FPR vacuum line re-attached)
That also matches what the Bentley says - so the FPR *seems* to be working fine.
BUT, after shutting down the engine, fuel pressure is gone (0 psi) within 1-2 minutes. Hm. Pulled the fuel rail and ran the pumps - no leakage (did replace with 16 valve injectors, since it was on my list ;)). Pulled the cold-start injector, too - no leakage. Looked under the car...no leakage! Faulty check valve on the brand new Bosch fuel pump? Didn't want to pull all of that again, figured I would see if you guys had any thoughts first.
I checked a few other things along the way - cleaned the IAC, checked it and the TPS using Bentley specs. IAC checked out, TPS did not match specs*** (900 with throttle close, 2900 at WOT). I pulled a used one out of the parts stash and threw it in even though it was off, too (1000 at closed throttle, 2600 at WOT). Might need to buy a new one at some point.
The intake hose had some issues as well..ScanTech. Had a spare (well, now the 242 doesn't have one ha!). Didn't seem to improve anything noticeably, but I'm happy I found the problem before it fully gave up.
Also popped the access cover off to check the in-tank pump. Found a mess of wires with butt connectors from a previous poor patching attempt. Don't have a spare sender, and the pigtails off the sender are extremely short (<1 inch), so I used ScotchLoks for now. Pump fired right up - will be replacing the sender when I find a used one.
I didn't want to fiddle with the fragile fuel level sender wiring, so I didn't pull the unit - might still have a hole-y hose in there.
I am most suspicious of the system's inability to hold pressure after shutdown - the fuel-level-sender hose isn't relevant to that issue. So, what do you all think?
Other notes and such (not relevant to diagnosis):
16-valve injectors - plastic and much lighter. Idle is smoother than with the 350k-mile 8-valve units.
***Don't know if this is in the Bentley errata yet: Bentley says to measure the resistance across terminals 1 and 2 - actually, you need to measure across 1 and 3. This is for LH3.1.
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Were you able to check if it is the AMM?
Somebody has been trying to sell a new LH3.1 AMM over on TurboBricks.
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This issue stopped in March or so, and suddenly came back a couple days ago. Any further thoughts? I am going to pull the fuel level sender soon, in hopes that there is some sort of obvious issue there..
The hesitation/stumble is pretty bad until the temp gauge rises to ~1/4 the way up. Under high load, it just falls on its face. Have to downshift and keep the RPMs high, throttle low, to keep it from stumbling.
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Hi there,
You said from your first post.
"That last note is probably the culprit (main fuel pump) - the pump is original (347,000 miles), but I just wanted to see if anyone had other advice. It seems like the car is running super lean. I probably forgot to add a few things - so ask questions if you've got 'em!"
Super lean! Yep, I am leaning alright, into what Art says, a fuel issue! No questions from me, just because of 347,000 miles on the original pump, yow!
I would have already changed out that pump somewhere past 250,000. Its been my experience that they can begin have intermittent issues, like hesitation to turn over at the first click of the key, when they get that old. Mostly due to worn brushes.
With this many miles on it you might have two things going on.
This is a roller pump which is pretty simple in operation. It is somewhat a positive displacement pump.
Lots of wear opens up clearances. The filter is where it is so that stuff stops there and not into the injectors.
347'000 has me thinking that you have probably lost a bunch of efficiency, just not dead, yet!
If you throw in those worn brushes, you should NOT have enough torque being generated to really run pressure up either. Pick a flavor!
That is, unless the pump itself is worn out so much that its bypassing fuel within the housing itself. All of it not going out but the pump hums.
It might explain why you are not hearing cavitation sounds, which are louder than normal, but sounds like an electric motor turning.
Yep, inconsistent buzz, I will buy into that game!
Advice coming at you!
Change out the pump, for the piece of mind. The pump owes you nothing. You are past any pro-rating and warranties. (:-)
I will also say that the firing up and running "consistently" is not an ignition issue. It's been my experience that ignition does not "wane" out. It misses or quits to function at all.
Do what Art suggest, I would.
There nothing like feeling a bulging going on and things are working well down there!
No matter where down there, is!
(:-)
Phil
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Spent an hour doing some more tests!
In-tank pump: Pulled fuse 4 and jumped the right side - no in-tank pump. Either it's dead or there is a wiring issue.
Main fuel pump: I managed to smack it (really hard) a few times while it was running - changed the sound and ran a bit better (more consistent buzz) actually! Think that might be the final diagnosis..
Fuel Pressure Regulator: Jumped the main pump and disconnected the FPR vacuum line. When I pinched the return line, fuel found the weakest link and leaked out of the hose connected to the FPR. Seems like the FPR is working fine (hose doesn't leak when the line is pinched).
Compression: even 160 across the board (sort of a leaky tester, but it's consistent!)
Injector resistance (Cylinders 1, 2, 3, 4): 16, 15.7, 15.9, 15.7
Checked the timing (timing light): 1-2 degrees advanced. Strange - maybe it slipped last time I replaced the cam seal while too lazy to remove the crank pulley.. Don't think it would cause this issue though.
Also, I cleaned up all of the engine grounds (wire brush). And sprayed carb cleaner around looking for vacuum leaks - none.
I think you guys had a good point - a lot of running solo without the in tank pump assist might have pushed the main pump to its final breath. I've got an aftermarket pump that I picked up cheap awhile back - I'll put that in. Does anyone have any experience comparing Genuine Volvo vs. Bosch vs. aftermarket (Airtex, Delphi, etc)?
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OK here is a true test of your threaded forum reading skills.
You posted:
"Checked the timing (timing light): 1-2 degrees advanced. Strange - maybe it slipped last time I replaced the cam seal while too lazy to remove the crank pulley.. Don't think it would cause this issue though."
I agree, this would not cause the issue. But your guess that your work on the cam seal had anything to do with however you determined the ignition timing was one to two degrees out of range is safely set aside. EZ116K ignition timing is not affected by any sprockets, gears, or belts. It is referenced from the crank position sensor and only adjustable by the EZK controller in the 6-crank-degree increments the tone ring can resolve.
What I find interesting is your timing light (perhaps adjustable?) might be seeing a mark only a degree or two misplaced. What, does the dial read 14 or something? I've never used one of those you can dial in and match the advance, so I'm curious. A slipped crank pulley isolator doesn't seem plausible for that small error.
--
Art Benstein near Baltimore
A man and his wife are sitting in the living room and he says to her: "Just so you know, I never want to live in a vegetative state dependent on some machine. If that ever happens, just pull the plug."
His wife gets up and unplugs the TV.
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Sorry for not responding sooner.
I assumed that turning the distributor gear one or two teeth might throw off the timing?
I just hooked the timing light onto the number 1 spark plug wire - my mark on the harmonic balancer showed up at ~2-3 degrees before TDC.
What should it be?
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It is 100% controlled by the computer. Your distributor just distributes spark to one of four leads. The Rotor in that distributor covers about 20 degrees of sweep.
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Ah okay - makes sense. I'd have to really spin that distributor gear out of whack to affect the ignition timing, then.
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It should be closer to 12 degrees on the crank +/- 2 degrees at idle. This is on the label on the strut tower.
Are you sure you are not reading the 10 as the zero mark since the zero is not marked on the plastic?
Study the spacing or the harmonic balancer rim for spinning on the rubber hub is possible.
The rotor should be directly under the number one cap wire terminal while on zero crank and cam marks.
The CPS does keep things on target to the flywheel but you don't want the distributor off its intended place.
The intermediate gear going to the distributor shaft could be off a tooth on the belt and was compensated for by turning. The engine can still run but possibly not at its best.
The width of the Rotor button contact is needed for "spark time duration" on the arc around the distributors terminal pins.
I would Roll things around and eyeball lines and things up just in case the light is correct.
Phil
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"Main fuel pump: I managed to smack it (really hard) a few times while it was running - changed the sound and ran a bit better (more consistent buzz) actually! Think that might be the final diagnosis."
But you just stated, "no in-tank pump. Either it's dead or there is a wiring issue". So fix the in-tank pump first as it was probably the culprit as it was starving the main fuel pump.
--
1980 245 Canadian B21A with SU carb, M46 trans, 3:31 dif, in Brampton, Ont.
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Well, I plan to replace both (have a couple spare in-tank pumps). I just want to determine what actually kept the car from running by replacing the main pump first.
I looked at my spare pump last night, and it is an Airtex pump. Seems like the terminals are completely different, and are much less protected from the elements than the original wiring. There are several bad experiences with the pump (with one good one from Art awhile back). Makes me unhappy to chop up the OE harness, too. I ordered a Bosch unit from RockAuto (needed a fuel filter anyway). Should be here within a week - I'll let you guys know how it runs after I swap it in.
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Just to be clear, Michael, I have not had any positive experience with an Airtex main pump in an LH car. Have not tried one. I'd probably not try one, either, because I know the Bosch is built to last a million miles, having had the opportunity to take them apart. And I would not like to re-terminate the harness in that area, so well-protected by the Bosch arrangement.
However, I keep using the Airtex 8778 in the tank. No failures yet. Pretty soon all of our cars will have one :-)
--
Art Benstein near Baltimore
Did you hear that they were going to rename the Hertz after Charles P. Steinmetz? The abbreviation will be CPS.
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Thanks for the confirmation on my Bosch decision!
Also, sorry for misquoting you Art - I see that it was a K-jet Airtex pump. Also, it only lasted for 15 years - what kind of lifetime is that?! ;)
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Yes, that k-jet pump is a different animal, and the decision to go Airtex was made by my car's PO, so the harness was already converted to ring terminals. I still wonder if I should have pursued a Bosch replacement despite all of the posts I read about that k-jet pump being scarce in Bosch. The internals of the failed Airtex did not impress me as being anywhere near as sturdy as those in a Bosch version I dissected.
--
Art Benstein near Baltimore
The Art Collector's Wife:
A New York attorney representing a wealthy art collector called and asked to speak to his client. "Saul, I have some good news and, I have some bad news."
The art collector replied, "I've had an awful day; let's hear the good news first."
The lawyer said, "Well, I met with your wife today, and she informed me that she invested $5,000 in two pictures that she thinks will bring a minimum of $15-20 million. I think she could be right."
Saul replied enthusiastically, "Well done! My wife is a brilliant businesswoman! You've just made my day. Now I know I can handle the bad news. What is it?"
The lawyer replied, "The pictures are of you with your secretary.”
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Quick update - I installed the fuel pump and a new fuel filter today. The pump sounds great - much smoother (quieter, too). The car ran decently, but still seemed to stutter a bit after idling for ~10 minutes, as if it would die again. I turned it off for an hour or so, then started it up and drove to the nearest gas station to fill up. For the first minute or so, the car bogged down (like it used to before it died), then something suddenly "worked" and all symptoms disappeared. The same exact thing happened after I restarted the car at the gas station (this time only for 10 seconds or so of driving).
All of that to say - I don't think the pump fixed the issue. I will replace the in-tank pump in a few days if I have time, and see if that helps, but I am doubting it.
Any other suggestions? I'll be driving it quite a bit tomorrow, so hopefully it doesn't act up again.
By the way, I found another issue when I pulled the fuel pump/filter assembly down. I'll have to replace the harness. It is just wrapped with electrical tape now to keep the wires from touching.
Lots and lots of rust coating all of the bolts, but somehow I managed to get everything apart without busting anything. Guess I can give Kroil all the credit for that ;)
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Drive to work this morning (humid and raining) was great. No hiccups, no hesitating..just the usual solid drive I am used to. Maybe the computer had to "re-learn" getting a steady signal to the fuel pump (after all this time with the two pump wires tapping each other and/or ground over every bump in the road).
Nabisco - I have a spare LH3.1 computer I have been thinking about swapping in, just to check. With the problem being so intermittent, I think I'd rather diagnose the cause of the symptom, and see if that could be ECU-related.
Art - I was thinking the same thing about Bosch pumps. I'm not going to cut it open - if I have time, I will use the little variable power supply I have and a container of gasoline to see how the 'ole pump fares.
Regarding fuel pressure testing: I have a '93 fuel rail with the schrader valve, but I don't think it will let me have the cold-start injector. Is that an issue? If not, I'll just swap that in and use the schrader port.
If it is an issue, maybe I should just go ahead and buy a fuel pressure tester kit (like this: http://wiseautotools.com/ta58012-volvo-14mm-lh-jetronic-adapter-with-quick-coupler/). I don't think I will have time to make a tool.
Michael
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Hi Michael,
Don't worry about the ECU control of the fuel pump. The only thing it does is switch on the relay. If those wires had been shorting together your blade fuse would have opened. And if the relay got "switched off" your car would die right there. But the fuel pump relay can be a locus of intermittent high resistance which is probably the most documented LH cause of death in Brickboard history. Replace or resolder is consensus advice.
As for re-learning, our LH2.4 cars are all a little stumbly for the first 10 mins after a reset. The idle is typically low and the urge to two-foot is a part of the re-learning. But I don't have any LH3.1 experience.
That kit is good to know about. Many would just like to buy the Bosch flare fittings and procure the rest at Home Depot. In 1999 I made many visits to auto parts stores looking for just those adapters before I found this forum and got the advice from Stoney to grab a fuel rail at the junkyard. Talk about having the time...
Anyway I can't tell you to sacrifice your cold start valve. In LH2.4 that would be simple -- just move to a 951 ECU.
--
Art Benstein near Baltimore
"How can I answer this and stay opaque?" Tina Fey
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Thanks for clarifying the Subject line. Brickboard is a little more difficult to follow than a standard forum (where everything is just in a line).
I ordered some tools so I can measure the fuel pressure. Found a way to spend more of the money on the generic tester (so it's more useful for other cars) and less money on the Volvo-specific part (14mmx1.5 fitting, mostly). Here is what I got (~$60 total):
http://www.langtools.com/sku-71305-volvo-adapter-14mm-lh-jetronic/
http://www.amazon.com/gp/product/B0009XQUKC?psc=1&redirect=true&ref_=ox_sc_act_title_1&smid=ATVPDKIKX0DER
I think that will do. I have been meaning to get a fuel pressure testing setup together in case something happened. Instead, I waited until something happened.
I'll update with pressure info, unless the car breaks down before then, in which case I'll update with what I expect to be more of the same issue.
-Michael
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"Thanks for clarifying the Subject line. Brickboard is a little more difficult to follow than a standard forum (where everything is just in a line)."
Yes, the advantage of threading -- keeping replies associated with their sub-subject -- can benefit the reader more often than the original poster, who must identify the new sub-topics which grow out of a generic thing like "my car doesn't run right." Brickboard provides the option of FLAT view, but, at least in my browser, the date info gets lost and the order of posting with it. It used to work years ago for me. I have not even tried to look into it.
This forum's custom software was once way ahead of the generics like vbulletin so many have become proficient at reading, reminding me of how we recognized BetaMax as a technically superior scheme despite popular acclaim. Have to admit it runs circles around the mail lists of the 90's. How many of us can still use WordStar? These RWD cars were designed then too.
--
Art Benstein near Baltimore
"Shun those who say we have eyes in order to see, and instead say we see because we happen to have eyes."
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I hated Wordstar. I loved Lotus 1,2,3. In the grand scheme of things, I do not miss either.
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Here's a thought, is the ECU programming "remapping" every time you start the car? Say, an intermittent short to the O2 sensor or something, and the ECU has to reset... ???
I know when I did a head job and restarted the motor it ran poorly until the ECU adjusted then suddenly ran fine.
Just a thought.
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Think an Airtex in-tank pump is just fine but have no experience with their main pumps.
The Bosch main pumps are beyond bulletproof! When I sold my 90 244 with 300k on it, the main pump was still going strong. Replaced the in-tank once. My 95 855 (one pump system) with 249k still has its original Bosch pump. I have an American truck-owning friend who can't believe how robust the Bosch fuel pumps are. He's amazed that my car still has its original fuel pump!
Good luck!
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"Unplugging the AMM or IAC (separately) did nothing."
Usually, with the LH3.1, if you unplug the AMM the car will not run or run very very rough with backfiring, so that may tell you something right there. From experience with my LH3.1 245, the car will not run with the AMM disconnected.
This sounds similar to an AMM failure I had with my LH3.1 system.
It is tough to test the AMM without a functioning AMM to swap in. LH3.1 AMMs are hard to find used and $350 new. Whatever you do, DON'T clean the AMM with AMM spray cleaner. That is what killed mine.
Also, check the connector from the ECU inside on the passenger side. It is up high on the center console near the firewall. Intermittent connection of that plug will act the same as a bad AMM.
Or maybe it is the CPS.
Maybe change the CPS for a "diagnosis via parts replacement"? Some people can swap it easily, others have real problems... Once you do it the first time it is not too hard. Cheaper to check than swapping a new AMM.
Good luck.
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Thank you everyone for the advice so far! I had ~20 minutes today to look at the car. The problem is a little more acutely defined now - Car started fine – but as it warmed up it stuttered worse and worse, eventually dying out after a minute or two. It restarted pretty easy after letting it cool a minute or two, only to die back down in the same fashion.
1. Thanks Art – didn’t even think about the ECT grounding in the block. I plugged it back in.
2. ECT – Resistance measurement matched the specs (it was at ~1.2 kOhm after warming up for a minute or two).
3. AMM – I concur with Nabisco’s comments on the LH3.1 AMM – the car doesn’t start without it ;) I keep a working spare with me in the trunk. Swapped that in, no change in symptoms.
4. Fuel pump fuses – Thanks again Steve and Art for the guidance. I opened up the wiring diagrams and read up a bit, just to clarify it in my mind. I powered the left side of fuse 4 using fuse 6, and the main pump ran. Choppy, though, not a nice consistent buzz. I couldn’t hear the in-tank pump – that’s on my list for checking tomorrow (see below for a longer list) – but I’m not really worried about that (vapor lock is highly unlikely in this sort of weather, car should run fine without the intank pump).
5. Ignition – Power stage connector looks clean (unplugged it to inspect).
6. Fuel – I’ll bring some starting fluid tomorrow.
Question: Advice on a fuel pressure tester setup? I’ve got an old fuel pressure gauge, but no fittings for it. Actually, come to think of it, I have a 1993 fuel rail I planned on installing so I could have the Schrader valve. I digress..
Plan for tomorrow:
Starting fluid (easiest place to spray that, and how much?)
Check ECU connector
Check Crank Position Sensor (swap with known good part)
Check Timing
Pull spark plugs and take a look
Check O2 sensor (if car runs)
Check In-tank pump (right side of fuse 4 w/out fuse 4 installed)
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"Choppy, though, not a nice consistent buzz. I couldn’t hear the in-tank pump – that’s on my list for checking tomorrow (see below for a longer list) – but I’m not really worried about that (vapor lock is highly unlikely in this sort of weather, car should run fine without the intank pump)."
Choppy is not how it should sound. You're right, vapor lock is not something you worry about in this weather. Maybe you could call it something else besides "vapor lock" to understand why the main pump isn't getting fuel to it so it will run smoothly -- not choppily.
Because you say it runs choppy, I think you have a fuel problem, not an ignition problem. Your starter fluid spritz will help confirm, but consider taking my advice on checking fuel pressure without all the correct tools. It is quick and easy, and you having more than one 240 gives you the opportunity to see how it should feel on a working car.
Run the pump(s) with a jumper and squeeze the return line to feel the flow. If it is flowing back to the tank, you know the fuel regulator is maintaining the pressure it is designed to, taking the leap of faith the regulator hasn't failed in an abnormal way.
--
Art Benstein near Baltimore
After eating an entire bull, a mountain lion felt so good he started roaring. He kept it up until a hunter came along and shot him. The moral: When you're full of bull, keep your mouth shut.
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"It restarted pretty easy after letting it cool a minute or two, only to die back down in the same fashion."
Maybe the ignition amplifier (power stage) is defective.
"Power stage connector looks clean (unplugged it to inspect)."
Try a spare instead.
--
1980 245 Canadian B21A with SU carb, M46 trans, 3:31 dif, in Brampton, Ont.
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"Jumping the right side of fuse 4 to the left side of fuse 6 did nothing - no pump buzz.
Hooked up a spare ECT (just let it sit in the engine bay) - no change
That last note is probably the culprit (main fuel pump) - the pump is original (347,000 miles), but I just wanted to see if anyone had other advice. It seems like the car is running super lean."
HillBilly explained the wiring at fuse 4. Your test really begs the question asked: did you do this with good continuity through fuse 4? In other words, what you did should have had both pumps buzzing, but none would buzz if BOTH fuse 4 were open and the tank pump were dead.
Thing is, the tank pump can be dead for years and you won't know it, if you keep the tank fairly well filled and are not driving in the hills in July. You know that.
Anyway, I believe changing the main pump on mileage or suspicion is a mistake. That's just me. See In the Tank again. But maybe it is time for you.
If you substitute the ECT like you mention, you need to provide a good ground between its body (threads) and the head. It is a three-terminal device.
My first suspect given last night's weather would be ignition despite your assertion the cap 'n' wires were in good shape. How about the power stage connector?
Basic check has you getting a can of starting fluid, so you can prove the problem is fuel if that's what you suspect. If you do then, maybe you could devise a pressure gauge connection like many of us have, or in most cases a squeeze of the return line with the pumps enabled will tell you the rail pressure is up.
The 1990 wiring: The left side of fuse 6 is powered separately from the 25A fuse under the hood, so if you use that as a power source, you are bypassing a possible red wire/blade fuse trouble.
--
Art Benstein near Baltimore
If you're riding' ahead of the herd, take a look back every now and then to make sure it's still there.
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"Jumping the right side of fuse 4 to the left side of fuse 6 did nothing - no pump buzz".
If fuse #4 is defective or blown, it would prevent the main fuel pump from running with it hooked up like this.
The power into the fuse block comes from the battery (+), through the 25A in line fuse, and onto the left side of Fuse terminal #6. It's a big red wire. The primary contact on the fuel relay is powered (continuously) through this fuse
The left side of fuse terminal #4 has two Yellow/red wires attached.
One of these wires is the 12V (+) power feed from the fuel pump relay, and the other is the power feed from the fuel relay (secondary contact) to the main fuel pump. These two wires are not fused at this point, it is merely a junction point.
When the fuel relay closes, it supplies 12V power to the main fuel pump, and power to the in-tank fuel pump through fuse #4. So if fuse #4 is blown, the in-tank pump won't run.
To jumper the pumps, connect the jumper between the left side of fuse terminals #4 and #6. The main pump should run continuously with this jumper installed. You can hear it under the car in front of the rear wheels, to the center.
The in-tank pump will also run as long as this jumper installed.....and....as long as fuse #4 is good. You should hear the in-tank pump if you listen through the fuel filler hole.....use a short piece of hose to help your hearing.
Hope this helps
steve
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A few thoughts:
1. Have you tested for fuel pressure?
2. What about intake manifold gasket and vacuum leaks?
3. Under hood corroded 25amp fuel injection fuse and fuseholder.
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1. I haven't tested fuel pressure - don't know how I would do that (outside of disconnecting the rail inlet line and watching it flow)
2. I searched around for vacuum leaks after I saw the vacuum gauge dropping. Didn't see/feel any. I could grab some carb cleaner and spray around, but the car won't even run right now.
3. I replaced the underhood fuse a while back with a nice waterproof fuseholder - checked it last night and it looks good (will check continuity later today).
Also - the FPR vacuum hose does not have gasoline (or a gas smell) in it.
Thanks for the questions - keep 'em coming!
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1. I have never done it, but I'm pretty sure that a fuel pressure gauge can be attached to the fuel rail so you can test the PSI to see if it meets specs.
What about the CPS?
How about the fuel injection computer (ECU)? Ever been replaced? A lot of 89's and some 90's had bogus computers. You can check the label's color to verify whether it is a good one. AS I recall, white is good.
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I've got LH3.1, so it has a 572 computer (no known issues). Although, the windshield has been leaking into the car on that side - maybe I'll give it a look!
Won't be able to look at it until later today, unfortunately
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