Cuting out Problems...

[wickedmotorhead]

I have a problem that I can't figure out.
Incident 1:
I just got my 87 GN and after driving it home about 300 miles it started cutting out and the service engine soon light would flicker every time it cut out. I stopped let it sit for a while then it was fine for the next few hundred miles home.
Incident 2:
Went out for a cruize about a week later and after a couple miles did the same thing and finally died. Let it sit for awhile and was fine after that. I drove it to work (30 miles) and back several times afterwards without incident.
Incident 3:
Drove it to Woodward cruise this Friday and Saturday. Friday no problems. Saturday without warning same problem.

The scanmaster gives no malfunction codes, no overheating (180 or below always), no particular rpm or speed. Has anyone had this problem or have any idea what it could be. Anyone had problems with vapor lock in these? Any help would be greatly appreciated since this is my daily driver.

 

[SFITurbo]

Ohm out the coils, if good I'd lean towards the module under the coils.

 

[pacecarta]

same thing happened to me tonight , drove it around all day today getting a feel of the new rear contol arms and had no problems . and when i was cruising out of town at around 30mph almost no load for about 3/4 mi it just cut off sputtered lightly and died (which of course caused the service engine light to come on), no smoke , pulled over noted temp only about 170 popped hood thinking maybe a turbo hose slipped off (even though i didnt have it under boost) and everything looked fine , got back in , turned key and she fired right up and drove home 5 miles with no problems , checked codes and none stored
I replaced the coil last week because it ohmed out high on two coils (12.3) and out of spec (14.2) on other coil (it was the original87 coil) . the new one checked perfect (11.4ohm) on all three coils and its been running smoother than its ever been . since its all that i changed recently I double checked my wiring of the coil and all checked out correct , yellow/blk # 1, grn/blk #5 , blue/blk #3 all others to even side terminals . looks like ill be trying a new module, maybe its time to drop in a type11

 

[wickedmotorhead]

I'm a rookie at this, by Ohming out the coils what do you mean and how do I do that? Thanks.

 

[pacecarta]

your coil pack is actually three coils in one pack , pull off the spark plug wires and check across the towers on the ends of one coil with an ohm meter , youll have three reading to take and the readings should be close to each other and around 11.5 , i think higher than 13ohms is considered out of spec

 

[wickedmotorhead]

Well,

I Ohmed the coil out and got 11.78, 11.78, and 11.73. Looks to be ok their. I personally believe that its a fuel starvation/pump problem. I believe it has the stock original in tank pump and an outside auxilary pump which I've heard isn't optimum. Where would I get a good in tank pump like a Walbro and what do you recommend. What do I all need to make this change over? Thanks again.

 

[ACME RACING]

Are your spark plug wires ok, new ??
Mine has been cutting out and changed spark plug wires and found the old plug wires had rust on the inside of the end plug that goes on the coil....now it runs ok... No missing.. Should have done this a year ago .

 

[GNX423]

when it cuts out does it backfire badly? i chased down a simular problem that turned out to be the crank sensor, but when mine cut out it sounded as if the exhaust was going to blow off.
Good luck,
Mike

 

[WIKEDV6]

Check and see if your ECM is ok, sometimes if it gets wet from water leaking in, you may have the same problem. Is it a T top car?

Prasad

 

[superballs5337]

GOOD LUCK! my car has had this same problem, ive done what everyone in here has said. and im still chashing the problem. im starting to start back over and replace everything with ACDELCO stuff. maybe thats my probelm but who knows. i love this car its just been a pain in the arse.

 

[JeffW]

Originally posted by SFITurbo
Ohm out the coils, if good I'd lean towards the module under the coils.

I'm with you SFITurbo. I've had this problem before and it ended up being the ignitiion module. Also make sure the plug wires are in good shape like ACME said.

Sometimes these ign. module issues don't show up until the engine, and thus the module, get warm. If you need a good source for an inexpensive module/coil pack, let me know and I'll email his name.

 

[MGTTYPE]

Check the grounds that go to the back of the head and on the tranny bellhousing on the passanger side. If the check engine light comes on while it sputters that is an indication that for a split second the electrical circuit thinks the car has shut off. I had that problem and just moved the grounds to one of the intake bolts and problem was solved. Mario mgttype

 

[sumnerw]

When I had a similar problem (engine would cut out or die once it got hot but would restart immediately, no codes) it turned out to be the brand new Wells ignition module. Put a used, AC-Delco ignition module in and no more problem. Nothing but AC-Delco electronics for me after that one.

Good luck,
Buzz White in Houston, TX