All,

I have a 1998, S70, auto, non-turbo, 170k.

The car has been very much trouble free ever since we bought it in 2016.

Recently, it has developed an issue, and seems to be related to humidity or dampness, where the car when cold will start up with out issue, but then if you drive it just a couple of miles or less, which is about enough time for the engine to go close loop, and then shut it off to run an errand inside a home depot for instance, then come back out, it will not start. This has happened to my son several times and well, its now time to finally find the problem and fix it.

What we've done is this: Removed Idle Air Control valve and cleaned it. I've also remove the distributor cap and rotor and cleaned it, though it is not very old from a mileage stand point.

I was also thinking of removing the throttle body and cleaning it, but I have not done that yet.

Also, the temperature control circuit in the air filter may be dead, but I've disconnected the exhaust exchange into the air filter, so that should not be an issue if in fact the thermostat is in fact toast.

There are 0 codes on the car as well.

Before doing anything else, I'd like to hear from the board and see what you all say.

Thanks in advance,

Matt

--
1989 - 245, 1990 - 245, 1991 - 245, and 1993 - 245

Well, the unthinkable has happened.

I pulled the distributor off this morning, and well, oil every where inside the cap.

The rear intake CAM seal is out and leaking into the distributor, most likely causing my hard start problem.

The really bad news is that I'm gonna have to pull the oil pan and find out how plugged up the return line is from the oil separator box. Most likely completely plugged.

This would explain the oil consumption issue that was noted on the last oil change. I also performed the glove test yesterday and it was limp; not filling up, not sucking in. My guess is that if the seal was still in place it most likely would be filling up.

This repair is going to take awhile to do, so don't look for any response anytime soon as it is getting cold here in Maryland.

Lord willing the rear intake seal is as bad as it will get for seals. Hopefully the rear main hasn't been affected, but only time will tell. Also, hopefully I haven't taken too many miles off the engine, but again, only time will tell.

Thanks for listening, now time to start tearing it apart.

Matt
--
1989 - 245, 1990 - 245, 1991 - 245, and 1993 - 245

If you take the intake to look at the PCV/ oil separator to check the ports. You can check how plug they are by hooking a plastic hose attach to funnel and add some solvent. The solvent might be able to dislodge any crude on behind, just change the oil w/ a cheap brand and dump after few minutes.

Humberto,

Thanks for the advice!

So after pulling the intake, I was able to look into the bottom tube that goes into the oil pan and determined that it was not plugged after all.

I put a new PCV system on the car and called it done.

I also pressed in a new seal and the car is no longer having an issue starting after warming up. I believe this to be a huge crisis adverted.

The lesson learned here is that I should have replaced both rear CAM seals when I replaced the CAM sensor seal a couple of years ago and I did not. Literally a ticking time bomb.

Chalk this up as don't do that again.

Later,

Matt
--
1989 - 245, 1990 - 245, 1991 - 245, and 1993 - 245

If the boot is still torn at the throttle body, don't forget to replace that. It will make the engine run rich and foul plugs.
--
Keeping it running is better than buying new

KlausC,

Yep! Its on order.

As soon as it shows up, I'm going to install it.

Its probably been rich for a while. Dang it!

This is what happens when you don't drive the car on a daily basis!

Matt
--
1989 - 245, 1990 - 245, 1991 - 245, and 1993 - 245

Air filter thermostat is a non issue. Idle air control is a non issue. Cleaning throttle body, won't hurt. Cleaning PCV wouldn't hurt.

I would recreate the problem in my driveway, just drive 2 miles roundtrip. Then you have time to pull the plugs and check for over rich condition (wet). Check the resistance of the ECT sensor, with the thermostat open, the reading should be around 250 Oms. A high reading would indicate a bad ECT.

A vacuum leak around the intake manifold, anywhere past the MAF will cause a rich condition.


--
Keeping it running is better than buying new

KlausC,

One more update for the day.

So I've been isolating my time on the ECTS, and well the connectors from the ECM are just toast, and nasty and I've now cleaned them to the best of my ability, and here are the results of my labor.

The last test was as follow(s):
Took the car for another test drive, and when I got back I did the following:
At 0 time, I measured the resistance of the ECTS to be 255 Ohms.
At 15 mins past 0 time, I measured the resistance of the ECTS to be 350 Ohms, attempted to start car, and it started without hesitation.
At 30 mins past 0 time, I measured the resistance of the ECTS to be 512 Ohms, attempted to start car, and it started without hesitation.
At 45 mins past 0 time, I measured the resistance of the ECTS to be 720 Ohms, attempted to start car, and it started without hesitation.
At 60 mins past 0 time, I measured the resistance of the ECTS to be 933 Ohms, attempted to start car, and it started without hesitation.

I put the whole assembly back together after a long time off, started the car once more, and waited for it to get up to temp, at which point I shut it off, and waited 15 minutes. Then attempted to start it, and it started right up.

So either the ECTS is intermittent, or the connection was so nasty as to cause a higher than normal resistance back to the ECM. Either way, I ordered a new ECTS and thermostat and will replace both once they get here next week.

Hopefully there should be no more issues once this is done.

Let me know what you think.

Regards,

Matt
--
1989 - 245, 1990 - 245, 1991 - 245, and 1993 - 245

Good job, you deserve a beer!

When you put the new ECT in verify the wiring is good - which is probably the root cause of the problem.

And be careful with the T40 bolt on the thermostat, loosen the front a single turn, then push down hard to get the rear bolt off. You will need to dump about 1 quart of antifreeze into a clean container and reuse it when finished.
--
Keeping it running is better than buying new

KlausC,

Got the new thermostat and ECTS today. I put them both in and ran the card to operating temperature and then shut it off for 10 minutes. I then went out and attempted to start the car, and it once again would not start, so I'm now at a loss as to what is going on here.

Any additional thoughts would be greatly appreciated.

Thanks,

Matt
--
1989 - 245, 1990 - 245, 1991 - 245, and 1993 - 245

Hi Matt,

I follow your posts when you put in your advice to other tabs here on the board and for this to get you down this hard, it must be a very elusive problem!

The idea I would like to put forth is this is a no start problem related to heat soak situations since it’s the only time it keeps doing it.

In my opinion to keep hammering on the ECT sensor isn’t so logical at this point. The ECT is really only a fuel trim system and not a fuel shut down system.

I want to say that the electrics on any system are heat sensitive. In this case it raises its ugly head after shutdown or during the restarting or during cranking phases.
Something is failing to give a signal or receive a signal that the engine is trying to start.

You don’t mention any flooding of the cylinders and what the ignition is doing right then?

To cut to the chase and reiterate the fact that something has stop talking to another component.
I will have to contend that these newer cars use Crank Position Sensors that are known in the 240s to fail.
Failure of these things, in many cases, we’re not catastrophic in nature and that, in itself, raises its ugliness during this startup scenario!

I know nothing about FWD and AWD cars or the engines and how many cylinders they have or don’t have. But I do know they all have sparking coils and paraphernalia leading up to do just the same darn things!
Your car won’t start hot and so can our 240s!

I would be scoping out putting in one of those Crank sensors, if you haven’t already, or combing over the wiring connectors since this is a 22-23 year old car!
If I had an engine with multiple coils, with no spark wires or rotor button, that would still leave me looking for a distribution system, that can have flaws!
A whole set of bad coils is unlikely but one power supply or input line is all you need!

Oh know, here comes a story!

When I was a teenager, I had an Italian motorcycle that used the old type brush DC generator.
It would quit charging when it got temperature or vibration.
Took it to the shop twice with the light on and leaving it running to confirm the problem to the Unauthorized Harley Davidson dealer/mechanic of an old man but his patience prevailed!

A stator winding had a cracked wire that grew longer and shorter with heat and separated like a tree twig in a wind. It would slip sideways just a hair and quit charging.

Why couldn’t the same thing be going on with your car?
You got to find out, which one, of the two sides of the FIRE TRIANGLE is not present under heat!
I think you are reaching, in mind, just not body, yet!
(:-)

Good luck!
Phil

Phil,

So I'm still looking at stuff. Hopefully getting closer.

After replacing the ECTS and still no joy in whoville, I went dark and performed the following:

0) Heated the car up as usual, waited 10 to 15 minutes, and then attempted to start the car, at which point it did not start, so...

1) replaced ECM with another one, and the engine fired up and ran for shit. Wrong year ECM!
2) replaced Original ECM, and car started right up, even though it had only cooled down for 10 to 15 minutes since the original shut off.
3) removed and replaced relay 2/32 and 2/53, Car again started right up and ran.

So now, the car will start up and run fine just as before, but now I can not get it to die on command like before after a 10 to 15 minute cool down. There is however a new symptom that is present. After the car has cooled down (10 t 15 minutes) I can start it just fine, however, if I smack the throttle from idle to say 4000 RPMS several times in succession, there is a minute hesitation that occurs and I think eventually goes away, but I will verify this tomorrow. As for the Crank Position sensor, it was replaced in 2018, so I'm not even digging into that, as was the CAM position sensor.

Tomorrow's festivities are as follow(s):
1) Attach fuel pressure gauge one more time to be used later.
2) Install my noid light into each injector to verify that they all do indeed work, or at least that I'm getting a signal there.
3) remove throttle body, check resistance of TPS, and then clean the throttle body, and then reinstall it.
4) Run car through warm up test, then shut off and let it cool for 10 to 15 minutes.

At this point there are several things I want to look at: Fuel pressure, how long does it take to bleed down, are any of the spark plugs wet (Yeah, I know, KlausC asked me to check this earlier, I'm lazy!), check the injector signal again with the NOID light, and will it start again after 10 to 15 minutes. I'll keep track of everything and report back.

My leaning right now is a cold solder joint within the ECM. I have a friend who is a Electronic Technician who can look at all the connections under a microscope and determine if in fact any of them are cracked. If there are, then he will reflow them and most likely we will be back in business and we'll call this one done.

I'll report back later in the week with results as I'm pretty busy this week.

Thanks to Phil and KlausC for asking great questions and pointing me in directions that I may not have wanted to go.

Regards,

Matt
--
1989 - 245, 1990 - 245, 1991 - 245, and 1993 - 245

Hi Matt

I want to remind you, I do not know anything about the front wheel drive cars. I have never looked under a hood of one any farther than to give it a cringe 😬!
I think you are on the right track now by placing 👀 peeping windows in strategic locations.
One noid light will tip you off to a failing injector firing system.
All injectors are fired in pairs or strings by grounding “almost” continuously in order to get enough gas into the intake and to the cylinders fast enough.
Those Pistons are flying, even at idle, with parts of a second to work.
Pulse widths times cannot be seen and is irrelevant in this case of a failing to start issue. No oscilloscopes needed.

It appears that the clues are pointing to this is an electrical thing. You have scared it by being very close, Since you moved those couple of items and the symptoms changed!
This, even though those items are not affected by engine heat per say but could be from operational use or components heating some.
I like the idea of cracked solder joint but connector clips, are even better and some under the hood.
Have you ever applied a thin film of corrosion prevention? I like a salve or LPS One or Two for a light dusting and check for deformities
The AMM connector on the 240s are notorious for releasing after years of earlier guesses and hunting.
Not that a AMM causes a fail to start, HOT!

Since this is 1998, you might still have ignition spark plug wires so would a timing light be an option or is it not?
I don’t know what other means are used to check for live sparks on these cars with coils over the plugs?
What can you do but lay a bunch of neon bulbs over the top of the engine and look some glows?
Like checking for a microwave spread pattern?
I know, a AM portable radio! (:- ) the RF static pop!

I can understand the laziness to dig into the top of these plastic capped engines of today to access those spark plugs.
I’m not real great in pulling those of my own 240 red blocks and their right there! (:). But they can give up some very definitive information, in their stories they tell.
Gas Fouling or not?
The other choice is getting caught kneeling and smelling up the butt of your car! (:) 🤥(:-)🤫

As far as the hesitation happening that could be a myriad of things going on with breathing of the engine and the dealing with abrupt fuel mixture changes since there no load on the motor.
The fuel management program is not going to match up to such conditions so repetitive, especially with a used exhaust system of this age.
The adaptation of “adaptive learning” adjustments, in 1998, was still on drawing boards for the most part.
This issue might be what DEALERS say, “ oh, it’s a characteristic of the car.”

You might have to accept, that it’s Now Acting, like the humans that made it? (:-)


Phil

All,

There is still just no joy in whoville today!

I did run through my list of items as posted last night, but nothing.

NOID light worked on all injector wiring harnesses, and
TPS was within resistance range at both idle and wide open,
No cold solder joints on the ECM.

So why did pulling the ECM cause it to change behavior????

I do have a small vacuum leak at the boot going into the throttle body, but would this cause the car to not start after it warmed up? I'd love to hear about this.

Also, to add insult to injury now, when I did move the car today back onto the street for the next car in need of maintenance, there was a large patch of oil on the driveway. What might have caused that to happen, any ideas????

I did get the car to get into that state again, but only once. I was however able to start it almost right away. It has a very bad hesitating on blip-ping the throttle, but only after it is warmed up, but this too comes and goes. This hesitation issue is not seen on a cold startup.

I'm about at my wits end and am close to taking it to a good INDY in the area, however the new to me, oil leak is very disturbing and I would like to know where this is coming from before moving forward to an INDY to tell me what the issue is.

As always, any thoughts would be greatly appreciated, even it they are the same thoughts, maybe I just need my head beaten in a little bit more.

Thanks in advance,

Matt
--
1989 - 245, 1990 - 245, 1991 - 245, and 1993 - 245

Hi Matt,

That dying problem sounds like the year old KAE fuel controller 2/32 in my 1995 850. It would get hot with use, and the engine would quit,
and start working again when it cooled down. It got progressively worse.
I replaced it with a new Stribel relay and it solved that problem.
Keep a new spare in the car.

Good luck, Bill

I still think it is the wiring at the ECT sensor. You proved that before installing the new sensor/thermostat. It is worth going over again.
--
Keeping it running is better than buying new

When I did check the wiring before I checked for voltage, which was 5 VDC.

What I didn't check was voltage after warming up. I will do that tomorrow and get back.

Matt
--
1989 - 245, 1990 - 245, 1991 - 245, and 1993 - 245

KlausC,

I'm able to recreate the problem when ever I want to now.

Before the last go round, I checked the resistance, and it was about 1.2K Ohms after say about 1.5 hours of just sitting outside. Outside air temperature about 45 degrees or there abouts.

I was able to jumper across the two wires and get it to kick off and run.

I then hooked up the ECT and took it for a drive, brought it home, and shut it off. I checked the resistance again and it is about 350 Ohms, and now I have a new condition where the cooling fans wants to run when I shut it off, the car that is.

I also no longer have any readout on my dash telling me what my engine temperature is, so that is some what disturbing, hopefully dead shoring the two connectors did not fry that gauge.

So, I'm not convinced that the ECT is bad, but then again it might be. Thoughts?

Thanks in advance,

Matt
--
1989 - 245, 1990 - 245, 1991 - 245, and 1993 - 245

I did a search for- hot start problem - and found - 700/900 Hot start problem quick reference guide

While I am sure that most of it does not apply to your problem, it does give a couple of suggestions such as a bad gas cap (???).

The old saw - fuel, air, and ignition - I think your problem is fuel related

Let us know what you find.

In older cars, trouble with hot starts is sometimes caused by fuel seeping into the intake manifold caused by expansion of the fuel when hot and a bad needle valve.

How do you start the car when it is hot?

Since there is pressure in the fuel system, the problem could be a leaky fuel injector, (I have no expertise in this area, just brainstorming) or a pressure regulating problem.

I have read that if you hold the gas pedal to the floor when starting, no new fuel is sent to the engine.

If this tactic works, your problem may be flooding of the engine caused by heat.