|
|
Well, the story of this car is: I purchased it 2 years ago with a broken timing belt for $100. I replaced it, and a water pump 200 miles later. 3000 miles later the voltage regulator went and I replaced that. Other than that the car ran great, with no major issues until....
Three months ago I started having trouble starting it on a cold morning (I think around 5 degrees F). It seemed sluggish to crank and false started a few times. It took about 20 tries and then it finally started. I thought his was odd because I had consciously noted how easily it had started on cold days in previous winters. I drove it that day and had similar problems getting it started to go home. I checked it out and found a coolant leak. The upper seal on the water pump (into the head) went so I put in a new pump (when it wasn't so cold). I also timed it to 8 deg. below TDC (which I now believe to be incorrect) and put in two new belts to the alternator. I also located a vacuum leak on the line running to the After that it started and ran consistently for about 2 weeks. I didn't have any problems and no coolant leaks. Then more cold weather came and the problem re-appeared. It also seemed worse. I couldn't get it started one day. Then more days came when it wouldn't start.
On occasion it would turn over and the engine started to run but for only a few seconds. I tried priming it by turning the ignition back and forth to get fuel in the line, but it didn't seem to make much difference. I tried holding my foot to the floor and leaving it off with the same results. On rare occasion holding the accelerator halfway in while starting the car would result in the engine starting and running at high RPM but as soon as the slightest release from the accelerator it would die. I tried just about every starting variable combination I could think of...
So I started with the Fuel Pump relay and LH System relay. They clicked while I turned the ignition but to be sure, I tried swapping them, I tried pulling them out and keeping them warm, I tried cleaning the contacts and rotating fuses, etc... I located some Bosch replacement relays (the parts store crossed both relay numbers to an updated version, same part for both as it's an LH 1.0). Those didn't help... I got a fuel filter, new plugs, wires, and new fuel line from the filter to the rail and a new section on the return line. I tested the fuel pump also and it cranked. I checked the resistance on the fuel pump wires that are easily accessible underneath the rear passenger seat and the resistance was low (good). After all that it started great!!! I was so excited, until 6 hours later when I was driving home. It died in the middle of the road... twice (on a street named Broadway). I got out in the middle of the street and fiddled with the fuel pump and wires and got it going again both times (thank god!).
So moderate or warm temperature seems ok, but cold temp seems to kill it. I guess, maybe I should have focused on that problem more. My only unchecked thought is that the timing is off and that is doing it? I was reading on one of the threads that the LH 1.0 is 12 deg below. I thought I set it to 8 below from my shop manual but now I think the manual is wrong for my engine. Could that throw it off enough to cause these problems in cold weather. I also have the White Cap distributor (MPG), could that be part of my problem too?
I just wana drive my wagon!!! :(
Alex
|
|
-
|
|
|
Have you checked your 25 AMP fuse (driver side fender, under hood) ? Gunk on fuse/ in fuse holder ?
Just a thought.
Enjoy.
--
84, 242GLTi, 167K, 4+OD, still in rehab; 89, 245 DL, 318K, M 47, daily driver; 93, 245, auto, 167K ; and other toys.
|
|
-
|
|
This LH 1.0 car doesn't have the 25 amp fuse.
It still uses fuse 7 as the main FI fuse.
--
Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
|
|
-
|
|
|
I'm no metallurgist, but I think that temperature can affect electrical contacts that may be "marginal" due to corrosion, oxidation, and/or mechanical tension. So here's where I'd start:
Fuse 13, Fuel relay coil
Fuse 7, Main power thru relays to pumps, ECU, etc.
Fuse 5, Tank pump (but not apt to be a show stopper, IMO)
Also the Coil primary connections, especially #1 (negative). The LH ECU requires Pulses from Coil #1, and will shut the FI system down if doesn't get them (or won't START).
I have a simple schematic that shows a connector in that wire between Coil #1 and ECU #1 wire. I don't know where it's physically located, but to me it's another suspect.
Next time it fails, if you are getting spark at the plugs, try a jumper from the Left side contact of any fuse 6 thru 10 (always hot) to the Left contact of fuse 5. This will put +12 right where the Fuel relay does/should, but bypassing it and forcing the pumps to run.
NOTE that this jumper won't help on an ECU or Coil #1 pulse type problem.
I believe your timing should be 12°±2° before TDC, but doubt the 8° has any effect on the start-run problem
--
Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
|
|
-
|
|
|
Thanks for the suggestions Bruce,
Well, today was warmer. I tried to start it and had the same results. I double checked all the resistances to the fuel pump and all wires had low resistance. I tried to start it again and it fired and ran.
I corrected the timing to 12. I also found a ground wire that snapped and reconnected it. It was totally unrelated to the fuel circuits, but it couldn't hurt to fix. I it had warmed it up in the driveway for about 30 minutes and drove it around for about 20-30 minutes. Once I got back I parked it and shut it off.
I decided I should get voltages for the relays and fuses for the 'off' Ύ], acc Ώ], run ΐ] and start Α] states. as I turned to 'start' the engine would turnover and fire (like it should). I would then return it to the acc or off state and try again to get the voltages for start. but after 3 or 4 of these starts, it didn't want to start again. and since then it has not started.... ARG! so I'm going out to check the ignition coil connections and the connector between terminal #1 on the coli and #1 on the ECU (if I can find it).
a.
|
|
-
|
|
|
Before any more checking or measuring, I'd say the first thing is to be certain there is (or isn't) spark at the plugs when it fails.
There is no point in checking fuel-related items if it's actually an ignition issue, because ignition problems will by design prevent (or stop) fuel system operation.
That old white-cap Chrysler distributor could be a problem, given its age and reputation for fragile foil conductors, or something like that. I don't have any actual experience to back that up though. Many people replace it with the Bosch unit, adapting wires and plug as needed.
1982 was a transitional year too, and there might be wiring (connector) issues in the Coil Primary circuit, where the wires followed the previous Bosch path, and are known to lose the +12 to the coil.
I don't like to beat a dead horse here, but you don't know for sure that you have a fuel problem until you have verified trouble-free ignition at the time of failure.
BTW, what shop manual do you have? It might aid future exchanges if we can be "on the same page".
--
Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
|
|
-
|
|
|
I just checked for spark with my timing gun. the coil put out a signal, and I got pulses to all 4 cylinders from the distribuitor. It's hard to visualy assure I have good quality spark by my self, but I think that proves I have a working ignition system.
|
|
-
|
|
|
OK -- we'll say the spark is OK. Did you try forcing the pumps, as I suggested before, bypassing the Fuel relay with a fuse jumper?
That Fuel relay doesn't get picked until coil pulses (while cranking) reach the ECU, and the ECU puts a ground on it.
The click when you turn the key on is just the System relay.
Try the +12 jumper to fuse 5 (Left side). The pumps will run immediately. So if spark is OK, it should start.
And your shop manual is...?
Check with you tomorrow.
--
Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
|
|
-
-
|
|
|
I've reviewed this thread and am still unclear as to whether the pumps (Main at least) ever run at all on a No-Start condition. In your first (1/24) post you say, "I tested the fuel pump also and it cranked". But how did you "test" it? Did you jumper +12 directly to it? If not, at what point was the +12 applied?
As you can probably see on your Haynes diagram*, my 1/24 suggestion to jumper from the Left (hot) side of fuses 6-10 to Fuse 5 eliminates Fuse 7 and the Fuel relay as potential suspects. But I don't see a clear response to my 1/28 question: "Did you try forcing the pumps, as I suggested before, bypassing the Fuel relay with a fuse jumper?"
You did say yesterday (1/29) that: "I jumped the #5 fuse and had the same no start results.", but did the pump(s) run with the fuse jumper (as a test) before you tried starting? If so, that means it failed to start with pumps running (which can happen), and we have to look somewhere besides the fuel circuits.
So again, do the pumps run when +12 is jumped to Fuse 5 input? I meant for you to verify that before you tried starting, but failed to make it clear. Please try again. Even working solo, with the fuses jumped you can reach under the car to hear and feel the Main pump—and go around to listen for the Tank pump at the filler pipe. You can also test the pumps individually by removing fuse 5 and putting the jumper to either fuse contact.
I'm also a bit confused by your neat table (relay diagrams are nice too)—specifically the "run (engine idle)" column. Was it running when you measured those voltages? I would hope so, because they look OK to me, the key points being cranking and running voltages from the System and Fuel relays. But I'd also like to know what they read (cranking) when it fails to start. That might give us more to go on.
* I have two Haynes manuals, 74-90 and 76-93, but not the 74-84 you mention below the table. Am I missing a 74-84 edition? Because I do see an LH diagram on 4A-26 in my 76-93 book. It looks like a Volvo greenbook pictorial. My other LH 1.0 diagram is in a 1982 Clymer manual, and looks like a copy of a greenbook fold-out. From what I can tell 1.0 is pretty close to LH 2.0, but for ECU terminals and some other things that I don't suspect at this point.
--
Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
|
|
-
|
|
|
Hey Bruce,
Ok to clear up some of your questions...
The Fuel pump was tested when I replaced the fuel filter. I removed it from the bracket, cleaned it up and tested it straight off the battery (with a fused link) in my hand. It had plenty of torque, so I think it's fine.
I did jump the #5 fuse on the 28th, but I think it was jumped from the wrong side. So that test was probably invalid. I re-tested this tonight, results are below the table.
The table column for 'run (engine idle)' was from when I had it running on the 28th. The last column 'start' is during cranking when the engine failed to run. I never recorded data for 'start' when engine runs since it was unpredictable when that would happen.
Regarding the Haynes, I found this copy in a thrift store. It is for 74-84, printed in 84. Looking at the copyrights, there may also be publications from 81, 78 and 77 if you're hunting them down. I've looked at the Bentley manual and it looks great, but doesn't cover my engine or year....
ok, so new information:
I did check a few more voltages last night for the pumps. This should be appended to the table above:
| - | connected to | off | acc | run
(engine off) | run
(engine idle) | start | | Fuel Pump | | Yellow Wire | - | 0.00v | - | 12.30v | - | 10.80v | | Pre-Pump | | Light Blue wire | - | 0.00v | - | 6.90v | - | 6.90v | | Black/Orange wire | - | 0.00v | - | 0.00v | - | 10.8 |
I fixed the pin on the ECU connector (#24). it was bent and just needed a little attention. After checking my LH 1 diagram, I find it's a redundant connection for the O2 sensor anyway. It didn't have any impact on the starting issue.
I just want out and jumped left side #7 to right side #5 and the pre-pump was running. However, with #5 jumped, the main pump wasn't running (I grabbed it and didn't feel any vibration). I also jumped #7 to #13 which I now believe was the dumbest thing I could have done. Anyway, after that I tried starting the car with #5 jumped and it started up! I smelled something in the cab, almost like burning, but it didn't last long.
...And now I have a new problem.... it revs really high all the time. It starts great, with out any effort. but revs higher than a 'cold start' and it doesn't want to 'kick down'. I checked the accelerator cable and linkage and find them in working order. argh! So this eliminates the fuel pumps I think.
|
|
-
|
|
|
Alex,
Glad the car seems OK now, but must comment on some points:
"I did jump the #5 fuse on the 28th, but I think it was jumped from the wrong side. So that test was probably invalid. I re-tested this tonight, results are below the table."
"Wrong side" would be the output or fused Right Side fuse contact. That's why I've tried to stress jumpering to the LEFT (input side) where Fuel relay voltage is delivered. By jumpering to the output (wrong) side, the voltage goes unfused to the Tank pump—and backwards thru fuse 5 to the input and only then to the Main pump. In this case, a bad fuse 5 or contact at either end would block (or reduce) voltage to the Main pump.
Well, I can't tell for sure what you meant there by "wrong side", but on 1/24 I made a point of saying, "...jumper from the Left side contact of any fuse 6 thru 10 (always hot) to the Left contact of fuse 5...", and again on 1/28 at 20:07, "Try the +12 jumper to fuse 5 (Left side)".
Yet in last night's final paragraph above, you say, "I just want out and jumped left side #7 to right side #5 and the pre-pump was running. However, with #5 jumped, the main pump wasn't running..." Very likely the Main pump wasn't running for the reasons I suggested above—running the voltage backwards thru an unknown fuse and its contacts. Sorry, but this is straining my patience.
I'm afraid we've become entangled in a thicket of detailed, esoteric measurements and tables, while stumbling over specific, basic tests that are known to help isolate problems in the relatively simple fuel control circuit. I see in your next post that the car is now running. I have no clue as to why, but seriously doubt that "discharging capacitance" was a factor. Inadvertantly restoring a faulty fuse connection would be more likely, I believe.
I can't draw any conclusions from your latest table, but assume the Main pump was running—given the 10.80v in the "start" (cranking) column. As for the Pre-Pump part, I don't know of any light Blue or Black/Orange wires, so the odd voltages are suspect there. The wire to the pre-pump is yellow/red, changing to black at the final connector in the trunk.
Bruce
--
Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
|
|
-
|
|
|
Sorry Bruce,
you are correct, and my post was incorrect. I jumped from the right side of 7 to left side of 5 last night. My first attempt on the 28th was backwards. sorry again for any confusion. I thought I had made a mistake the first time and came back inside and re-read your post to get the correct sides. I must have just transposed the numbers/sides in my post.
as for the wires running to the pre-pump, I believe the black wire ran to the pump and light blue to the sending unit. Both were in the same harness connector. I coded the wire as Black/Orange because it's black after the connector and orange before. There is also a connector between this connector and the fuse where the capacitor is spliced in ( I still haven't located this one) as shown in the LH diagram I have. The diagram also lists the wire as Red-Yellow, but I have orange for some reason (maybe replaced some time ago).
I'm considering checking voltages again to see if anything is behaving differently now. Do you think this is a waste of time?
It ran great today. no stating isses, no stalling.
Thanks again,
Alex
|
|
-
|
|
|
Hey Bruce,
Well, it had trouble starting today. I jumpped #5 the correct way and heard the pumps running. I then truned to start and it started after two tries. It was going great for the first 15 minutes, but then it died while I was driving to work... I tried jumping to #5 again and didn't hear any pumps running... I'll try to get it back home tonight on the way home. seems like the connection to either of the pumps is not that stable.
Alex
|
|
-
|
|
|
Good news!
ok, well I found a loose connection to the CIS and now it starts and runs fine. I've started it and driven it a few times now. seems to be running. The loose connection was my fault, I did it yesterday.
the fuse jumping changed something (discharging capacitance?). it runs with out the jumper, and doesn't require it to start either. I only used the jumper to test the pumps as listed in the previous post, and once while starting. since then I haven't needed it. I'm still not certain what the problem, was, is or could still be. at least a few things have been eliminated. I'll continue to work on and drive it for now. do you have any other ideas? why would jumping it once have such an impact? I'm going to try to put together a web page on the LH 1.0 system. if you have any input on this specific early EFI system, please send it my way.
Thanks again for your help!
Alex
|
|
-
posted by
someone claiming to be jrewing
on
Mon Jan 30 02:29 CST 2006 [ RELATED]
|
|
not that it has anything to do with it but those voltage readings on a running car don't speak well for the alternator belt and regulator work done.
|
|
-
|
|
|
I agree as well as my friend who stopped by yesterday. My best guess would be that when the water pump seal went, coolant leaked on and into the alternator. I didn't actualy do the work on the regulator replacement. I took it to a local starter/alternator shop and had it checked out. The guy there replaced the regulator for $35 and said the rest was ok. so I can only assume the rest is ok... I don't have any idea how old it is, maybe original? It looks like it's been on this car for a while now. It was just a bit pricy at the time to get a new one, but I could probably afford one now. The belts are only a month or 2 old now and tight. just something else to fix...
|
|
|
|
|
