Yea I replaced my crank sensor based on info I found on the net even though I was sure that was not the problem. I even rang the sensor and all values were in limits but I went ahead and bought a new one in hopes it would take care of the problem. Amazing how much money I am willing to spend to keep my wife from griping and bitching about her car.

If you have a old cpu heatsink laying around they make a great ICM upgraded heatsink. Temps here have been close to 105 and still have not had a problem yet.

 

Dude, you are right about A-Zone parts, I wasted $ on two ICM's and ended up buying "Borg Warner" made in USA for $75...fixed the problem, those AZ units would last about 6
months here is the desert of Nevada..I also added heat sinks from radio shack, works great....rizzo


What sucks is autozone does not carry a better ICM so I can't ask them to upgrade me to a better unit. The only option I might have is ask autozone to refund my money and buy a AC delco unit but I bet they wont do that for me.[/quote]

Dude, where did you get that blue heatsink? that is the bomb! ....later Rizzo

helo, you would think that with all the 1,000's of complaints about 1990's
S-15/jimmy 4.3L or "any" vehicle with those engines..there would have been a recall on the f-pumps and ICM's or other electronic control devices? have you heard of any? I spent days reading about this very issue on the net, hundreds and hundreds, doesnt seem to be a solid answer................................4.3L..dies when hot!!


rizzo

 

That blue heatsink was from a old computer I happen to have had in the garage. I think it came from a thermaltake cpu heatsink. I just took the fan off.

 

Only TSB I've heard of that may be related is for the (recommended) upgraded spider assembly, which I have not yet purchased (couple hundred). The electronics don't seem to be the ultimate culprit.

2 years later, my problem remains. Last summer I determined it was fuel temperature related and my spontaneous engine shutdowns could be avoided for some length of time after topping off my tank with cool(er) fuel. On the flip side, the problem would occur more quickly with a light tank and would still happen after an hour with a full tank. After driving an hour away, I had the engine cut out over 20 times in 25 miles on my return trip. Parked for an hour and drove another 20 miles no issue.

The only things I haven't tried are replacing my (now) leaking injector spider and replacing the entire engine wiring harness. It's not my DD anymore, so I procrastinate in bolting cash onto rusty frame rails.

 

What temp is the car at when hot. Should be roughly 165. Check coolant temp sensor and thermostat isnt stuck open. This truck can run like complete crap if they are not functioning

 

I wish it had been something idiotic like that.

So anyway, I did the MFI upgrade. Can't say I'm 110% certain that the issue is gone now, but I'm fairly confident so far. I'll post back if it happens again.

Delphi FJ10565. [Hopefully] the best $$$ I ever dumped into my blazer (ordered from amazon). Of note, the delphi kit I got contained the bracket FH10098, even though I found numerous sources saying I needed to order it separately. The old poppet bracket will not work, though. 1-2 hour install. Engine idles so smooth now I often don't know if it's still running when I pull up to stop lights.

HTH future readers.

 

Its been a while but did the heat sink fix the problem? My 95 is doing same thing, spent way to much repairing from repair shop swapping parts.

 

It took a while but it has died with the heatsink. Not sure what I want to do now. We just don't drive it on long distances anymore so we haven't had the problem in a while.

 

im not a mechanic so these forums are very helpful. My 95 blazer starts right up goes for maybe 20 to 30 minutes then dies. Wont start up right away but will eventually start. Yesterday was a little different. After stallling waited 10 min. drove 30ft and died again. Then drove 10 min home with no issue. Had 2 fuel pumps replaced by repair shop,1 under warranty. Thinking its pump again. Whats your thoughts.

 

Ignition module would be my first thought but the first thing you need to do is check to see if you have fuel pressure when it is in its stalled condition. If you do have the correct fuel pressure then it is not a fuel pump problem. You can get a fuel pressure gauge at harbor freight for a few bucks and that will be good enough to check the pressure.