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420A 2gNT Engine dies while driving.

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Aday320

Probationary Member
11
0
Aug 2, 2015
Troy, Montana
Okay, I'm new. I looked for about 20 minutes to find a problem like mine. There were some somewhat similar ones, but not quite the same. I drive a manual 99 eclipse 420a non turbo by the way.
So today I was driving from Montana to Washington, and after a couple hundred miles my car died. Everything was normal, I was doing 80 on the freeway and then all the gauges dropped. There were no immediate warnings, the car wasn't surging, nothing. The only warning was the check engine light which had came on about a week ago. While coasting, I tried starting it but it wouldn't start. After coming to the side of the road and stopping, I tried starting it back up. It fired right up and I figured all was well, probably just hiccuped. I got back on the road and as I shifted to second it did it again. So I pulled back over and popped the hood. I checked all my fluids and took off the gas cap to see if I had pressure. Fluids looked fine although I didn't hear it release any pressure when I unscrewed the gas cap (I had nearly a full tank). I got back in and took off very slowly. It seemed to drive just fine for about 10 minutes when it suddenly died again. I pulled over and decided to let it cool off for about 20 minutes. This seemed to work as it waited about 30 minutes after I left to die this time. Throughout the remaining couple hundred miles to my destination it randomly died 6 or 7 more times. I noticed it always died when I hit about 4k rpms before I shifted. So I drove very mellow and kept the rpms between 2 and 3 thousand. This definitely helped although about every half hour it would die again.
On the way I stopped in at an O'Reilley's since they do free diagnostics. The only code it gave me was for a bad O2 sensor. I don't have the code number right now but it was the second sensor which is the one behind the catalytic converter. The lady at O'Reilley's said this is a very likely cause of my car stalling. I'm not sure I believe her 100% though. Tomorrow I plan on getting a new O2 sensor somewhere and hopefully I'll be able to install it soon (I don't have any tools over here though I do have some family who should).
What do you guys all think? Other things I was considering were ECU, Coil, Vehicle Speed Sensor, and Fuel System related parts. Has anyone had issues like these? I'm really hoping to get it fixed on a relatively small budget.
 
It's very unlikely (like astronomical IMO) it will be the 2nd O2 sensor which only adjusts ignition slightly for emissions. Plus you said that CEL started a week ago anyway. These intermittent failures are very difficult to pin down and can be anything. Some things come to mind are: bad tank of gas (started after last fill-up?), fuel filter clogged, leaky fuel pressure regulator, CAS, ECU, coil.

Does it seem to be temperature related for a component failing with temp? You could heat components (ECU, CAS, coil) with a hair dryer while idling to see effect.

Or is the fuel supply being cut off starving it (measure fuel rail pressure).

First thing I'd check: Perhaps a connection gets loose. Start by making sure the battery terminals are clean and tight. Also that the battery is tied down - a wobbling battery can short the positive against the hood. And have a rubber insulator on the positive terminal. If not that pull/move/twist all other connections/wires while idling to see effect.
 
All that stuff^^^^^^^^

I just finished chasing this exact same thing down on a 98. What I found was the engine wiring harness coming from connector A-32 had a group of wires that were missing their shielding. If you follow the "motor" fuse down, connected to it are two red-black stripe wires. One goes to the PCM, the other to connector A-32. It is under the intake. On the other side of the connector is the run of wires that goes to everything on the motor. CPS, CRANK, Coil.... Etc. Follow it over the bell housing before it splits and goes to the firewall. Included an image of the connector from the manual. This is where I found the bad wires. Hope this helps.
 

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Thank you for your replies. I tried driving it again after it was completely cooled down, and as soon as I pushed more than half way down on the gas pedal while in gear, it did the same thing. I only run premium in my car, and since the problem started happening I went through 10-12 gallons of new fuel which should have cleaned out any bad gas. Also, some of the roads I was driving on yesterday were extremely bumpy with the stiff suspension the car currently has on it. And most of the time when it died I was on a smooth surface. These two things kind of narrow it down to not being heat related, and not being a loose or bad connection anywhere. It's probably safe to check over my wires anyways though, so I will do that today. I'm also going to try and get an O2 sensor put on today. I'll give you guys an update later!
 
look at your spark plugs. they'll tell you the story of how its beeb running since they've been in. cavalier i used to have would randomly die when driving. even on a new engine. had a cooling fan that wouldn't work so itd get hot and as a chevy usually is, itd die. i also had detonation going on at that time to. never found the cause but it went through 9 sets of spark plugs. itd smash the electrodes together or break the ceramic and let the spark jump. gotta love doing highway speeds and your engine randomly die. sounding like a chain on a rollercoaster pulling the train up the hill. but look at your spark plugs. even if theyre new, detonation will kill a spark plug fast
 
Well I went to O'Reilley's and ordered an O2 sensor. I'm not going home tonight so tomorrow I'll pick up my new sensor and and head to my car. I'll check the spark plugs and replace the O2 sensor and hopefully she will run again.
 
I certainly would test the o2 sensor with a good multimeter before installing the new one. If you install it you can't return it.

The general consensus on this type of repair is always going to be the same. You're going about this in the wrong direction, if you just buy random parts and throw them at the car. You will continue until you have no money and the car is still running the same. You will do what you want, but I wouldn't buy anything until I was sure it is needed.
 
Most likely it's throwing another CEL when the car is dying. I was on a long trip the other day and thought I was either getting fuel cut or a misfire. The CEL would flash but not long enough for me to read on my pocket scanner. After checking all kinds of other stuff, my gf commented that the radio also shut off for a second when it happened. Long story short, my strut bar had worn its way into the wiring leading to the battery. DUH:ohdamn: Anyway, you wouldn't know this because of the 02 CEL.
 
Thanks for all the help guys. I'm by no means a mechanic, so most of this stuff I will be walked through by my father. When testing the O2 sensor, which wires should I test?
 
I took it to an auto shop and had them put it on the scope and do diagnostics. They said the crank and cam sensors lost power when it died. They said more than likely there was a short somewhere before these sensors causing the engine to die. They recomended another shop that focused more on electical. I called the shop and they were booked for a few days. Now I'm not sure what to do. I would put a new crankshaft sensor on it but the shop told me that it probably didn't need one.
 
I took it to an auto shop and had them put it on the scope and do diagnostics. They said the crank and cam sensors lost power when it died. They said more than likely there was a short somewhere before these sensors causing the engine to die.
How would they know it lost power when it died since I assume it was running when they looked at it? Anyway, if that's true you probably lost the 8v from PCM pin 44 to them (which also goes to vehicle speed sensor) somewhere along the way (or a possible short there), OR you lost their sensor grounds which go to PCM pin 43 (along with other sensor grounds). Whatever, it's intermittent on something else like vibration, poor connection, low voltage, etc which is going to make it very difficult to find.
 
check the crankshaft position sensor, when they start to go bad they can kill the car

Bingo.

I took it to an auto shop and had them put it on the scope and do diagnostics. They said the crank and cam sensors lost power when it died. They said more than likely there was a short somewhere before these sensors causing the engine to die. They recomended another shop that focused more on electical. I called the shop and they were booked for a few days. Now I'm not sure what to do. I would put a new crankshaft sensor on it but the shop told me that it probably didn't need one.

The CPS on the 420a is extremely erratic and it sounds exactly like what a CPS does when it's on its way out. I've had the same issues with 420as, even the v6 avengers.
 
Tps connector or tps connector cables cuts and asc relay next to fuel pump relay that your problem.relay when hot turn off
 
Alright. Today my cousin and I assessed the wire harness. We found one wire that needed a little attention. We cleaned it off and wrapped it with electrical tape. We also changed the oil, which was really thin and black especially since the oil was changed about 2k miles ago. We pulled the CPS and found it soaked in oil. We cleaned it off, put a new o-ring on it, (the old one looked okay) and put it back in. I took my car out for a drive and it seemed to run good at high rpms for a minute. Then it died. After it died it routinely continued dying at almost exactly 3,400 rpms. I'm thinking that after running for a minute it might've gotten oil back on it and that's why it started dying again. Do you guys think that's plausible? Tomorrow I think I'll try a new CPS and hope for the best. Also since the engine dies at almost the same rpm every time I was wondering if it could be the coil. But from what I've heard the coil usually either works or it doesn't. So I'm back to thinking the CPS is the problem. Any way to keep it protected from oil? I think there's a few oil leaks and I'm not sure where they are. The car doesn't go through oil very fast. I think it went through less than a half quart in the last month and that was the thin oil. We put heavier weight oil in it today hoping it wouldn't leak as much. Thanks for all the help so far guys! :)
 
Sounds similar to my problem couple years ago, runs normal after letting it cool down... Turned out to be the ignition control module. Has happened to 2 different DSMs that ive owned with the same symptoms, let it cool down for a few mins and its good again for a while
 
Spades, did your car die at a certain rpm though? Because mine dies at pretty close to 3,500 whether it's cold or hot. But after about 30 minutes of highway driving even under 3k rpms it randomly dies too.
 
Not at a certain RPM, but rather when under moderate load. And when it would fail I restart after 5-10 mins and run normal again. I stayed off boost for almost a week until my part arrived but I was able to drive to & from work to get by
 
Hey all, it's been a while. I'm still having the same issue with my car. I've replaced the crank and cam sensors and I've put a new coil and plug wires on it. Just to recap, the car runs and drives just as it should until it hits about 3500 rpms which results in the engine shutting off. Almost like I just turned the key off, except the radio stays on. I believe this happens at all temperatures too. I am really leaning towards a faulty ECU. I found one online from All Computer Resources but after looking at their reviews I decided not to purchase from them. I'm not exactly sure how the ECU works either, can I go to a junkyard and pull one? Or do I have to have one made/programmed for my specific vin? Any help is appreciated, thanks.
 
Just in case anyone else having this problem stumbles across this, I finally figured it out. The vehicle speed sensor was shorting out, which cut power to the crank and cam sensors. I put a new one on it about a week ago (pretty easy with an 10 inch extension and a wobbly) and she's been running like a champ ever since. Thanks to the guys who tried helping me out before. It's nice to know other people love these cars too :)
 
i'm not quite sure about that. had a buddy with a 3000gt. speedometer stopped because his speed sensor wasn't plugged in. but still ran and drove fine. either way, as long as your car is running good again is the good part
 
i'm not quite sure about that. had a buddy with a 3000gt. speedometer stopped because his speed sensor wasn't plugged in. but still ran and drove fine.
Normally yes, but he lost the 8v (from PCM pin 44) to VSS due to it's shorting in/at the VSS. So that 8v also no longer appeared at the CPS and CAS (which also use it) which killed the engine.
 
I'm glad you finally (after 4 months) got it figured out.

No offense to Aday320 (cause we've all been there, including me) but LET THIS BE A LESSON TO EVERYONE. THROWING PARTS (GUESSING) AT A PROBLEM DOES NOTHING BUT DRAIN YOUR WALLET. The autostore person told him the 2nd O2 sensor was very likely the cause of the stalling because it had that CEL code. Well that's astronomical or in IMO not even possible (and the person should have known it). The 2nd O2 is to slightly adjust mixture/timing for emissions. And even if it is bad the ECU will just ignore it. So a very expensive part was purchased which had nothing to do with the problem. In addition the CPS, CAS, coil, and plug wires were also guessed at and purchased. The shop in post 13 nearly had it figured out when they
"put it on the scope and do diagnostics. They said the crank and cam sensors lost power when it died. They said more than likely there was a short somewhere before these sensors causing the engine to die."
If they had pursued it more (kudos to them btw), it would have saved hundreds of dollars and 4 months time to repair.
 
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