So I posted about this earlier and thought I had fixed the problem but apparently not. Here goes, forgive the length but this has been driving me nuts for weeks:

1999 Stratus ES, 2.5L v6, 146,000 miles and change

1. I tried to get to the CPS (car was randomly stalling at highway speeds and then not restarting for 10, 20 min.) myself by moving the EGR hose, snap a bolt that goes into the manifold and wind up with a leak from the EGR hose into the manifold. I start getting p300, p300+ codes I assume from a lean air mixture.

2. I get a mechanic to change the CPS, car starts and runs fine. I turn it off to pick something up, come back out and the car starts and then stalls immediately. I wait about 6 hours and nothing happens, car starts up fine, I drive it off.

3. Pretty soon the p300s start coming back, first just on one side but pretty soon the whole engine. I assume it might still have something to do with the EGR valve so I replace that, the intake manifold gaskets and fix the snapped bolt from my previous endeavor. Everything is torqued correctly and I go on my way.

4. Soon the car starts stalling at low speeds and in stop-and-go traffic. It's favorite place to stall was parking garages, taking heavy turns at low RPMs. I replace the IAT sensor and the TPS, give the TB a thorough scrubbing and the problem gets a little better, but doesn't completely fix itself until I realize that the speed control servo was unplugged the whole time. I plug that sucker back in and the car runs fine, still getting the p300 codes every now and then but generally no problems, until...

5. Just the other night the codes came back and I'm back to stalling at low RPMs or at sudden decreases in acceleration (speeding up then suddenly slowing down). Also, turning sharply left seems to affect my idle but not so much turning right. Coming from a dead stop the engine seems to over compensate (really jolts you off the line with a little bit of a hiccup because it feels like I'm giving it too much throttle) and speed up really fast, then if I stop too suddenly after that the RPMs will drop to around 200 and it's probably going to stall.

Right now I'm thinking it might be the Power Steering Pressure Switch, a part which my Haynes manual says a mechanic should diagnose/replace. I also think it may be my MAP sensor or, possibly, my distributor cap + rotor, though I feel like if this were a fuel or timing or spark issue the problem would be a lot more consistent (there are brief periods when the car runs with no problems at all).

Could the Power Steering Pressure Switch be it? What about the MAP? Maybe a clogged fuel filter? Maybe a fried ECU or a TCM? I'm looking for any help here. Thanks so much to everyone in advance.

 

Did you open up the wire harness going to the crank sensor? I have had the problem before. The wires were shorted together.

 

That would actually make sense. The mechanic who did the job said the wiring connector was kind of loose, so he said he had to tape it down to get it to stay. Do you think it could be as simple as a loose connector? Would the CPS be responsible for all these other problems?

Also, what's the easiest way to reach the CPS for inspection? From what I can tell it's way back in there...

 

Sure it could, but I would still open up the harness. Doesn't take much time and will only cost a roll of tape.

 

I'll give it a shot when I get home today...I think I can get to at least the wiring connector. I'll report back later.

One more thing, though: why would it only start stalling once I replaced the EGR valve? I didn't have the low RPM symptoms before I did the EGR...could the change in intake gases be a trigger for this problem?

 

Do you still have the old EGR valve? Unless you have the wrong EGR for you motor. Or something isn't hook up right.

 

I've still got the old EGR valve but I'm not sure what wouldn't be hooked up right, unless of course the newer EGR valve wasn't the right one (but then why would it fit so well?). I guess I can throw the old one on real quick as it'll make getting to the CPS harness easier.

I always assumed the misfires were from the EGR system anyway, especially since my screwing with that was what set them off in the first place. But then I figured replacing the entire system and fixing that snapped bolt would correct my original problem, unless the fact that I drove the car with the faulty system caused critical engine damage.

 

Update: So I replaced the MAP sensor and left the battery unplugged for about 2 hours. Car started up fine and drove great for 2 days. On the way home from my girlfriend's house last night (highway speeds) I got another CE light and it's the same as it's always been: p0300 then p030x's (they usually start with cylinders 1, 3, and 5 and then move to all/most of them).

The idle seems to be back to normal, but it still drops when I turn the car left at low speeds (no affect when I turn the car to the right). Everything else seems to be fine, no stalls *knock on wood*.

I'm going to replace the cap and rotor today and inspect all the spark plugs the whole way around. Is it possible that leaky EGR valve fouled the spark plugs by running lean? I've got this theory that I fried my intake sensors by letting it run with the misfire codes for so long--thus why every time I replace a sensor the car drives/idles better.

The other thing I'm considering is the ECU, since the car runs fine and operates normally if I just unplug it for long periods of time. Maybe this could translate into a fried computer? Or maybe a lack in voltage caused by the alternator/battery?

I'm just throwing possibilities out there because I don't honestly understand why nothing I do seems to fix this problem. I'm sick of sensor chasing.