Mechanics

ENGINE DIES WHILE DRIVING

1995 Mitsubishi Eclipse

Engine Mechanical problem
1995 Mitsubishi Eclipse 4 cyl Front Wheel Drive Automatic 180000 miles

The engine just shuts off while driving, sometimes it will restart once the key is cycled off and back on but lately it still wont restart, it trys but will not idle. If I remove the battery cable for a few minutes or let it set a while (may be heat related) until it cools off it will restart. No ECM codes. I have replaced the crank position sensor whit no change. This car has the 420A engine.
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Tim cline
July 7, 2009.




Hi Tim

Thank you for the donation.

When engine stallled, were the dash indicators lights showing?

Were you able to restart if the accelerator pedal is depressed?

When engine is running, what is the idling speed?

Does turning the AC on cause the idling speed to drop before stabilising?

KHLow2008
Jul 7, 2009.
When engine stallled, were the dash indicators lights showing? Yes once it has died but not before it dies. I have noticed a couple of times I get a couple of warning lights that seem like they shouldn't be on (brake, check engine) then they go away and no codes are present.

Were you able to restart if the accelerator pedal is depressed? No it trys to start, gets to about 400 rpm and dies again, over and over until the battery cable is removed for a few minutes or it has cooled off.

When engine is running, what is the idling speed? Normal idling speed is about 800 rpm.

Does turning the AC on cause the idling speed to drop before stabilising? It seems like it drops momentarely then recovers in about one second. Problem happens with AC on or off.

When the problem first started, it would stumble and die while driving at highway speed, I could put it in netural and cycle the key off and back on and it then would restart and run just fine, it has been very intermittent but gets worse with warmer weather.

I'm leaning to the ECM since interupting power seems to help. I can remove the battery cable and things seem to reset but it may go a mile or 50 miles before it does it again. It has happened while ideling and also at speed. Sometimes it just shuts off and sometimes it feels like it is missing ( for maybe 5 seconds) the shuts off.
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Tiny
Tim cline
Jul 7, 2009.
When warning indicator lights shows without any codes stored, it usually is due to power interruption.

From the information I would narrow the problem to either ECM, power supply/grounds or fuel pump.

ECM seldom goes bad intermittently but there are cases of bad contacts of the printed circuit board or leaking capacitors. If this is the case, removing the ECM for a visual inspection might show something. Check all connections for contaminations.

For power supply, check connections from battery, underhood fuse box to ignition switch wire.

The best time to diagnose problem is when it does not start. Test if it is sparks or fuel that is causing the problem. If it is sparks, then might be related to the ECM or wirings.

If it is fuel, it could possibly be an intermittently failing fuel pump. Test fuel pressure when it could not start.

KHLow2008
Jul 8, 2009.
Thanks for the advise. I've been carrying a spare ing. Lead and spark plug to check for spark when if fails. The last time it did it I tried restarting several times while I was coasting with now luck. I pulled off and attached the lead and spark plug and grounded it under the WS wiper blade so I could see it and the dang thing started right up (missing on one cyclinder since I had the lead off). I'll check out the ecu wiring power and gnd, sometimes just making and breaking a connection fixes things.

Tiny
Tim cline
Jul 8, 2009.
You are correct about making and breaking a connection solving problems.

If you need any assistance, just reply to post and I will getback to you once I am online.

Good luck to your undertakings.

KHLow2008
Jul 9, 2009.

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