87 2.8 mfpi hot start problem

[8728_brns]

Hi all,
As the title suggests my 87 2.8 won't start after it's been idling at operating temp. My son was driving this car for a year or two and never experienced this problem. When it's cold( or after 20-40 minutes of cool down) it fires right up. The car was sitting for about 8 months but was started up and let run a few times.
Any ideas folks?

[wrightz28]

Most common heat related problem: Ignition control module.

Sounds like a classic case. You can pull it out and have it tested by a reputable parts supplier. if bad, get a GM replacement, no substitutes.

Oh, and welcome

[8728_brns]

Originally Posted by wrightz28

Most common heat related problem: Ignition control module.

Sounds like a classic case. You can pull it out and have it tested by a reputable parts supplier. if bad, get a GM replacement, no substitutes.

Oh, and welcome

Thanks for your reply. Would I still have spark at the spark plugs if that module was suspect? The last time I tried doing a warm start, after about 20 minutes, and it didn't start I pulled a plug laid it against the block and observed a nice blue spark when cranking. Didn't notice any fuel on the plug at all.....
So far I've replaced the dist. cap, rotor, plug wires, fuel filter and air filters. The alternator and fuel pump was replaced within the last year or so.
Oh and the car has 210k kilometers on it but the guy I bought it from dropped a rebuilt engine in it which has approx. 40k klicks on it.

[malletslinger]

You didnt notice any fuel on the plugs, but could you smell any fuel? If not, you should consider checking the fuel pump relay and the fuel pump/oil pressure switch sender...this is not the oil pressure sensor that feeds info to the oil pressure gage, this is a separate pressure sensor and if it thinks the oil pressure is to low, then it will prevent power from reaching the fuel pump.
How is the oil pressure? If it is ok, then you might want to check and be shure it isnt malfunctioning.

[wrightz28]

Control Module sends a reference signal to the PCM, which in this case it may not be doing. Might as well just have it tested, usually free, but make sure it is tested several times, they can test googd once then bad a few times later. It's a transistor pack, subjected to heat, it will eventuall not function correctly. If it tests ok then I would persue a fuel problem.