420A Strange Stalling Issue

[1BadRS]

Car is a 1995 Eclipse 5 speed

I hope somebody has experienced this before and can help me out. I'm driving along and all of a sudden my RPMs drop to 0, I hit the gas and the car kicks back on and the RPMs return to normal. This kept on happening while I was driving, but as long as I got back on the gas the RPMs would come back up again. Then while sitting in traffic at idle which was too low to begin with the car wanted to shut down. I had to keep reving the motor to keep the engine going until traffic started to move again. The last draw was I let the car sit for a day, then when I went to crank it up it just kept cranking and cranking not even attempting to start. I towed it to my parents house and finally it started but same deal, it kept wanting to shut down and I had to kept the RPMs up high enough to keep it running.

I read an article on how to test the coil and it is within spec. I also have new plugs and wires. I put a fuel pressure guage on and it has good pressure while running so I think i can eliminate that.

Any input would be greatly appreciated.

 

[BLACKpsiECLIPSE]

Have you done any work to the motor? Install any aftermarket parts? Timing belt?... cams?... ect..ect..

 

[SpectreTalon]

Sounds like your ECU.

 

[BLACKpsiECLIPSE]

I had a problem with those symptoms and it was my timing.

 

[1BadRS]

Timing belt was installed about 5,000 miles ago, I will pull the inspection cover to make sure the marks are still lining up. Other than that no mods to the motor. It is just strange how this is happening out of the blue. It seems like some electrical issue a sensor or something gone wacky becasue the motor just drops to 0 RPM then comes back to life.

Is there anyway to test the ECM? mine has been reflashed or reprogramed already. How about any of the other sensors anyway to check if they are good? I have no codes just the 11 for disconnecting the battery.

 

[Locke]

Check your crank and cam sensors first.

Then check this --> http://www.dsmtuners.com/forums/showthread.php?t=259892

Then try swapping ECU's with one that is known to be good.

 

[4UH8ERS]

Don't forget about your TPS, it seems that your only effected when you let off the gas, so you might want to check it out.

(p.s if you going to give input on what you think the problem is, don't just start spitting out all these answers without any justification of why that might be it.)

 

[bob123131]

Not sure if its the same for n/a and turbo, but mine did the samething when my tps wasnt lined up correct.

 

[Locke]

Does it run rich at idle?

Don't forget about your TPS, it seems that your only effected when you let off the gas, so you might want to check it out.

I don't suspect it would be the TPS. At idle, the VSS shows no speed, so the ECU will still supply fuel to idle, regardless of TPS reading. You can disconnect your TPS altogether, and the car will idle fine, and drive alright.

I am not saying it is not the cause, though. I am unsure what will happen if it thought it was wide open.

 

[1BadRS]

Thanks for all the replies guys. I'll try all those checks this weekend when I get back to the car.

Just throwing this out there but I read in another post about a similar issue and people were mentioning a bad MAP sensor. How do I check to see if that is good? Also I would agree with the thought about cam and crank sensors, anyway to check if they are good or not?

The bad thing is all these parts are pretty expensive so I don't want to have to buy them if they really don't need replacing. However if I knew what was causing it I would gladly spend the money.

 

[1BadRS]

Just thought I would post and let anybody with a similar situation know what fixed my car. Since I couldn't find anyway to check the computer or sensors I was up against a guessing game as to what might solve the issue. I decided to pickup a new computer since its a simple change and that sucker fired right up. I'm so glad the search is over and I finally have my car back on the road. I hope somebody else that runs into this problem find this post helpful.

Thanks again to everybody that contributed.

 

[Locke]

The '95 ECU's do seem to fail more often than would be normal. Glad you figured it out, and let everyone know.

 

[bullettdsm]

The '95 ECU's do seem to fail more often than would be normal. Glad you figured it out, and let everyone know.

X2.

Really important that you post up your solution for future "searchers". When I have a question/problem I always start with a search. It's amazing the number of threads that end with no stated resolution.

MB

 

[1BadRS]

I agree 100% with you guys. I hate to search around find the exact problem I'm experiencing and then not seeing the feedback as to what actually caused the condition. I did read in other posts about the reliability of the 95 computer and I found a used one for $100 which in my eyes was worth the chance. Message boards like this are absolutly invaluable for this kind of information, and it really saves people like us tons of money by not having to bring it into a shop for diagnosis.

I have to say I'm pretty amazed that thing just died like that. I was lucky in the fact that it acted up for a couple hundred miles before giving up completly or I'm sure I would have been stranded on the side of the road somewhere.