Car stalls while idling once it's warm, help!

[tanstaafl4]

Originally Posted by joshjames023

...
My other problem with the car is one that it's had for as long as I know of, where it sometimes won't start and if it fails to start it takes about 10 minutes of sitting until it will start properly. Every time before I start the car I wait until the pump runs and the fuel gauge rises to decrease the chance of a failure. Mostly it fails when it hasn't been sitting off for at least10 minutes, like if I shut it off, run into Circle K for a drink, then come back out and try to start it. When it won't start it tries to turn over as long as I hold the key, but never catches, and trying to give a little gas doesn't coax it at all. If the car didn't do this the stalling wouldn't be as much of a problem, but I've been stuck in rush hour traffic around the mall before and it's not fun.

Thanks,
Josh

You did say you replaced the ECTS with a brass one, right? This is just how mine acted until I replaced the ECTS. Did you also check the connector for corrosion or clean it?

A malfunctioning ECTS causes the computer to "think" the car is cold when it's actually warm -- causing it to flood the car when you try to start it. After the car is REALLY cold, it'll start with no problem. Or, at least, that was my problem.

When I first replaced the ECTS I got another resin one -- it was all they had in stock. It was less than a month before I had to replace it again!

[joshjames023]

I can't post URL's till I have 15+ posts so if you copy/paste this and remove the space after "http:" it should work. This is the one I had put in, I assumed it was brass because of the color, none of them I looked at actually said brass. I did not put this in myself so the connector didn't get looked at, I'll check it and clean it next time I have the hood up.

http: //shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_Coolant-Temperature-Sensor-BWD_18480069-P_290_R|GRPSENSAMS_529635641___

This is a brass one right? And thanks for the tip! Hopefully that was the problem all along and I can fix it...Wait is it the tip that needs to be brass? If that's the case I definitely have the wrong one, could you link the right one? And does the tip have to crack to go bad or does the plastic one just not function correctly to begin with?

Thanks!

[tanstaafl4]

The part that sticks into your engine needs to be brass. The one in the picture looks right.

Make sure that you've got a good/clean connection, no broken wires, etc.

Of course, it could be something completely different.

What's the reading on your temperature gauge as the car is warming up? If it gradually rises (over a few minutes) up to at least 3/8 of the way up the gauge, I'd guess it's working right. If it's always got the same value or if it never gets beyond 1/8th of the way up, then there's a problem.

[joshjames023]

Ok I'll check the wires and plug asap, lately my gauge has been reading at 3/8 when the car is moving, but it goes up quickly to 1/2 to 5/8 when idling in drive or in park. We lost some coolant when we replaced the sensor and I finally put some more in, but the gauge still rises too quickly for my liking. I'm actually going to go outside right now since my car is cold and make sure it's filled to the full line, might as well check the connection while I'm out there.

[joshjames023]

Alright the plug for the ECTS looks fine and I can't see an faults in the wires either. Also I took off my EGR again and ran the car (while warm) for 10 seconds to clear the carbon out, then shined up the EGR real quick and put it back on. Hopefully the stalling is done with, next is to figure out the problem with it starting, if it's not the ECTS I don't even know where to start.

[joshjames023]

I've got a problem again, I went to pull my car forward 10 feet in my driveway today and the service engine soon light came on. I let the car warm up then went to Auto Zone and got codes pulled, P0341 Camshaft Sensor Error (my car does not have a camshaft sensor as I'm sure you know). But, on the way to the store I nearly stalled twice at the same light, had to gas it while sitting there to stop it from happening. The camshaft sensor error used to be up all the time randomly, but never affected the driveability as far as I could tell. My car is still driving smooth, it just wants to stall again...If this has anything to do with it, I've been driving around in performance mode instead of normal since the car was "fixed". Any ideas?

Thanks,
Josh

[joshjames023]

Ok fdryer I read some of your posts on cleaning the coil packs and ignition control module of corrosion to solve the P0341 problem. Could a fault with those also be the reason why my car won't always start? I can't get them off right now because my tools are too big to fit in to get the top 2 bolts off, but looking at the outside they look like they've never been touched.

[fdryer]

Definitely, even more so if "they look like they've never been touched". The mystery is the engine dying off at random. Get to the ignition parts for cleaning.

[joshjames023]

I cleaned the coils and the module, the metal plate of the module looked like it had been used as home plate before, so much dirt on it. Cleaned that off and there's a handful of little corroded spots but most of the plate is clear, the coils themselves are rusty on the ring that goes around them where the paint wore off, I can put up put up pictures later if necessary. The car started better and I didn't get stuck anywhere for a few days, but it's really bad again, stranded at Chipotle for 10 minutes this afternoon and it took 20 minutes to start tonight. My aunt said she had nearly the same problem with her Saturn, the car would crank but not turn over and it would take up to 10 minutes to start it. Also she said the car held her key in really tightly and didn't want to release it. All my keys have gold scrapings on them because my car does this too. Could the actual ignition cylinder (I think that's what it's called, where I put the key in) be my problem? And if I would need to replace that would I be able to do it or would my security system make that really difficult?

[fdryer]

At this point in recurring engine stalls I'm leaning torwards the crank position sensor (CPS). The recurrence when the engine is fully warmed and stalling seems to point at the cps so testing at the time of failure may verify it but risky if stopped anywhere not safe to suddenly jump out of the car to test for spark. It would be perfect if the stall occurred in a parking lot or at home in relative safety so its your call.

A spark test at the moment the engine dies and refuses to restart immediately would be the ideal moment to remove the coil wires (after noting firing order) and have someone crank the engine while you observe for spark across the coils. The lack of spark is a sure sign of a failing/intermittent cps. The only other part to fail in this instance would be the ignition module but more cps' fail than ignition modules. The cps is above and behind the starter, mounted with one 10mm bolt. Almost any auto store has it. Ignition modules/coils are cheaper from junk yards and work just as well.

The spark test is the best troubleshooting aid for many issues about the ignition system as it begins with the cps and ends as spark. The cps is at the beginning of the entire ignition system since it controls the pcm through the precise timing signals that allows the pcm to run the fuel pump, ignition system for spark, and pulse the injectors. No cps = no pcm to run the pump, ignition system, and injector pulses. The warm engine die-off at random is one of the worst case scenarios for cps failures as its supposed to operate at all temperatures while many here have posted similar issues with random dying while driving and having to wait before being allowed to start up and drive away.

[joshjames023]

Alright I will look into that, one thing before I do that though, last time I cleaned the egr and ran the car for 10 seconds without it, it ran great for about a week before acting up...am I supposed to gas it when the egr is off, and if I am how much? A little or full throttle? Everyone just said to run the car, I'm thinking at this point it was implied I was supposed to give it some gas. If I was supposed to I'm guessing the leftover carbon that never got blasted out is still the cause of my problems. I'm thinking this because in one thread a guy said "be prepared to make a lot of smoke" and I didn't have any.

[fdryer]

When the egr valve is removed, both ports on the manifold is open to the atmosphere; one is an intake port directly to the intake manifold and the other is the exhaust system port leading to the exhaust manifold. Leaving these ports open without the egr valve in place will allow any engine to run to full throttle as the intake port isn't blocked. The engine will rev quickly and reach its programmed rev limit around 4k-4.5k and stay there. No throttle needed. The exhaust port will blow out exhaust from the exhaust manifold and any carbon sticking anywhere in the exhaust passageway.

A faulty egr valve will cause the engine to drop rpm's, hesitate, stumble, or stall. The blocking temporary method is a way to tell if the egr valve is causing the symptoms just described.

[joshjames023]

Alright guys, I'm calling the car's stalling fixed! It's been a week and no hiccups or issues at all and it's driving better than ever. Plus, it used to get 29-30 mpg in normal mode and now it's getting 30-31+ in performance mode. I just took off the new egr a 3rd time, cleaned it so it's like new again, and let my car run for a full minute with it off. After that we sprayed some carb cleaner on the exhaust side up front and repeatedly started the car until the exhaust out the back was clear and the front wasn't spitting out clouds of soot. Now to get around to examining the ignition parts after finals this week. I may post again in a few weeks if I make any progress.

Thanks for all the help everyone, especially fdryer!
Josh

[joshjames023]

Hey fdryer, my fix by cleaning the valves under the egr only lasted 2 weeks. Since that time the car still stalls so I'm thinking I'll give it one more thorough cleaning to see if that helps, sound ok? Also I had a coolant leak and my SES light was on so I went to Auto Zone to pick up 3 feet of hose and check the code. It was the camshaft sensor coming up again. Also, when I went to leave my car wouldn't start so I had the guy come out again and check for a spark (spark testing) and not only did he see a spark, the car started with the 4th and 1st wires off the coil. After that I popped the wires back on and the car started right up, normally I would have sat there for 10 minutes trying before the car started. Does this tell us anything? Bad crankshaft sensor or faulty coil pack or ignition module?

Thanks,
Josh

[fdryer]

Well, this persistent stall can be either ignition or fuel related and both may be hard to monitor. A new cps would imply either the cps is intermittent or the ignition module is. Junk yard ignition modules and coils are cheaper than new and work just as well so it may be worth a junk yard set. A fuel pressure that's intermittent may be harder to troubleshoot unless you can leave a pressure gauge on while driving to monitor pressures.

To eliminate the egr valve altogether; use two quarters as blocking gaskets and leave them on for a week or more. Nothing will harm the engine running this way.

[joshjames023]

I finally got tired of messing with it and took it to the mechanic my parents use. He got an ECTS error to come up one time in 2 days of looking at it so that may have been over-tightened when we put it in, but his main concern is the fuel pump. My fuel pressure drops off very quickly when the car is shut off and goes to 0, for the times when the car won't start for 10 minutes it's because it takes about that long for the pressure to slowly build up until it's enough to start. I'm going to say that is the cause of the stalling, the fuel pump has always been bad in that it lost fuel pressure, I think it just got worse around the time the EGR was clogged and started stalling the car. Once I get it back it should start like a normal car and if stalling persists at all I'll go right back to the ECTS...kind of disappointed I didn't fix it myself though...either way my car runs much better than when I started thanks to you guys and your help!

Josh

[madpogue]

That fuel pressure drop is actually a common issue with the '97 cars. But it's not the pressure drop that's really the problem. What's of concern is:

Originally Posted by joshjames023

... for the times when the car won't start for 10 minutes it's because it takes about that long for the pressure to slowly build up until it's enough to start.

That just doesn't make any sense. Even if you intentionally dropped the pressure by opening the schrader valve upstream of the fuel rail, or by disconnecting a line, or by pulling the fuel pump relay and running it 'til it starved, the pressure should come right back up to 40-45 PSI when you turn the key to RUN, and the fuel pump runs for 3-ish seconds. Okay, maybe two reps of turning the key to RUN to run the pump, maybe 6 seconds of pump run time, max. If you're having to leave the key in RUN for 10 MINUTES to get that pressure, something's going on upstream of the fuel rail, i.e. filter, pump, pressure regulator, etc...

[joshjames023]

Well my car has been in my family since new and it's had this problem for at least a few years, when it won't start it's not that you have to leave the key in for 10 minutes, the car just has to sit for 10 minutes. It doesn't matter how many times you turn the key to on and let the pump run, it just won't start until you let it sit. I'm just trusting this guy because he guarantees his work and warranties it for 18 months or 18000 miles...I have pretty much eliminated everything except a fuel issue at this point...I really don't know much about cars but I've done everything these guys have suggested. I'm pretty sure it's just a really inconsistent pump that occasionally acts up. It's in his hands now and it should be back tomorrow so I'll post again with the results, hopefully they're good!

[joshjames023]

Well so far so good, no stalling and the car starts right up now with no waiting, problem now is my coolant leak. Replaced the hose that runs from the top of the reservior and that helped but then found the infamous driver-side tank crack in the radiator...

I bought some silicon sealing stuff and covered the crack and I have to say the stuff works really well but I'm told the pressure will eventually just blow it out of the way and continue to leak. Most likely going to order a new radiator tomorrow and just put it in myself, I'm not dropping another $500 like I just did on a mechanic. Only thing is that on these forums people say the Auto Zone Spectra brand tends to fail and the Delphi and Silla (I think it's those 2 brands) are the best. Anyone know who sells these? Or is the Spectra thing nothing to worry about?

Thanks,
Josh

[adventureoflink]

I remember someone here posting a link to the Delphi radiator on Amazon..