QuestionConsistently after running the car for approximately 5 miles on a warm day(70+ degrees F.) or approximately 35 miles on a cold day(35- degrees F.) engine stalls(dies) at any speed-can limp home by repeatedly parking car on the side of the road for about 5+ minutes, starting engine, and proceeding normally for a quarter mile at a time on warm days or a little further on cold days before engine stalls again. Engine is not overheating. Service engine soon light only comes on just prior to key switch engaging starter and when engine has stalled but never while engine is running. I think the problem is a temperature related breakdown(malfunctioning open and/or closed circuit(s)) somewhere in the electronic ignition system components. I have had both an auto service center and a Buick dealer with all their electronic test equipment, technicians, and service managers try to solve the problem. The original fuel pump, crankshaft position sensor, camshaft position sensor, MAF sensor, MAT sensor, engine coolant temperature sensor, and C31 ignition module have been replaced with new ones to no avail, and the C31 ignition module was replaced twice. When a static ignition spark gap test is performed on the ignition system cold before starting engine or warm before engine stalls the #3 and #6 cylinders are the only cylinders that will jump a 1/4" gap, before and after switching around the 3 coils’ positions on the ignition module, yet the engine will run perfectly until it stalls. I don’t understand why the ignition system won’t jump 1/4" up to 7/16" gap on all 6 cylinders. This indicated to me an ignition problem. Two years or so before this problem the engine would occasionally stall when coming to or at a stop, but it would readily restart and run beautifully. Then one year ago a radiator hose burst, the engine overheated, and I had to be towed to a service center for repair. About 9 months later the present problem developed. This car runs too good when it runs and is in excellent garage kept condition to just junk especially after spending so much money in vain to fix this problem. Can you help me? Thanks!
AnswerOuch!! Sounds like you have tried all the expensive stuff.
One thing I hate to say about swapping the parts, is, if something causes an item like a spark control module to go bad, and the module is replaced without correcting the cause of the first module to burn out, then the replacement is liable to suffer the same fate.
A poor ground someplace might cause that spark deficiency.
Make sure you have a good ground to the engine from the battery. That is probably fine, since you don't have a cranking problem.
Then, make sure you have a good ground between the engine block, and the car body, like the firewall.
Make sure there is a good ground to the ECM, and the coil packs.
Van
