magius231

My car has recently started randomly dying while driving down the road. I'll just be driving and suddenly it will shut off, then jump start itself again (M6) but it causes the car to buck back and forth every time it does it. It doesn't seem to care if the car is hot or cold, idling or driving, or what RPM although I haven't taken it past 3000 very often since it started as I don't want to lose the rear end if it does that during a first gear WOT pull. There are no other symtpoms that I can see, it runs fine, still barks the tires going into 2nd and 3rd, the PCM doesn't reset itself (none of the startup dash lights come on) and there is no SES light coming on. I played around with all the wiring to the opti, ICM, coil, etc and nothing caused it to die.

I did a search for other people with this problem, and found only 2 threads which matched my issues, but noone had a fix in there. Does anyone have any suggestions on things to check? Is there a way to get the coil/ICM checked or check it at home? I'm pretty sure theres no way to get the opti checked but if anyone has any suggestions that would be great, I absolutely cannot afford to just randomly throw money/parts at the car.

Thanks in advance!

944v8inDFW

You change the fuel filter lately?

shoebox

Do your idiot lights on the dash go dead, too, at the time it quits or do they light up?

magius231

the lights stay on, nothing in the dash lights up. I don't think I have ever changed the fuel filter, but if the filter was dying wouldn't that cause some performance loss, and maybe sputtering/popping and dying (lack of fuel symptoms) instead of just a sudden stop?

97bowtie

Check all your grounds. This could be a number of things, but sounds like a bad connection with the coil/battery. Does it fire back up every time or have you had to pull over and fiddle w/stuff to get it to start back up?

magius231

it has always started right back up. I thought about a bad battery connection, but none of the dash lights go back on nor does the radio stop playing. A bad ground is possible though, Where is the main engine ground located? I wiggled all the connections I coudl find with the elbow/MAF off and none of them made the car act any different...

slmdgmc

Mine did this, the coil wire was burnt at the connection on the coil. It would just randomly die, which really sucked. Mine wouldnt crank back up some of the times though, it would take it awhile.

magius231

that sounds exactly like mine...lemme run out and check that real quick

magius231

no deal - coil wire looks fine (didn't measure resistance though), its only 6 months old and still looks like its in good shape except for some white residue on the opti side plug. The coil is a used PS-91 that I picked up so I am not sure what condition it is in...

slmdgmc

Mine was at the coil connection coming from the engine harness, not the coil to opti connection.

Hawk350

Ever figure out what the problem was? Mine began doing this a few days back and I think it may be something with the fuel filter.....did you solve your problem?

bdc95ta

there shouldn't be white residue something's causeing that. I read a post a while back of people getting white residue on there opti. connections and there opti.'s kept on going out. Turns out they hooked up the one way air thing up wrong so the opti. couldn't vent. Or something along those lines.
-b

magius231

Haven't solved it yet, but some more things to check..

I haven't messed with the opti air vent any, but that doesn't mean it wasn't wrong when I got the car so I'll check that. I'll also check the connections at the coil and opti and see if any are broken. Thanks for the tips guys.

Does anyone know if you can have the coil or ICM tested?

superkia8

Man, Im very interested in how it turns out for you! A friend of a friend at the dealership installed a thermostat and every since then the car will do that same thing?

Good luck in your search!

magius231

in that case it sounds like they splashed coolant on the opti...bad news