Stalling when hot outside

[camshaks]

98 blazer 4.3 liter 4 wheel drive 140,000 miles
Chasing a ghost here...
fuel pressure is good
new fuel pump and filter
no engine codes
plenty of spark
car dies on very hot days in slow traffic and wont start until engine cools for an hour or so.
one day it stalled and it restarted VERY sluggishly, i had keep my foot on the accelorator and give it about 1500 rpm at stoplights to get it home.
very next day it was cold and it ran like a champ.

[muddog321]

Clean the MAF sensor first, then if an idle problem check the idle air control (IAC) on the side of the throttle body as they fail and the port inside gets crapped up. About a $70 part and had that go on an 01 with 90k recently. Have to remove the TB to replace and clean so use spray and a toothbrush. The rear bolt is that air cleaner one. Watch out that you don't loose the little clip off the cruise cable that comes off to pull the plastic TB cable end off.

[camshaks]

ok thanks muddog, ill check that out.

[camshaks]

ok, i cleaned the maf sensor and it stalled again a couple weeks later. this time it was while i was moving so i dont think it was an idle problem. a friend told me to change the round thing right under the distributor. changed that and its still acting up. now it drives ok then wont restart while hot. i come back a few hours later and it restarts. wtf

[Rick Norwood]

Are saying that you replaced the Distributor Module? Is stalling the only problem, or does it back fire etc. I have seen similar issues before. You might try replacing the spark plug wires, Rotor, and distributor cap.

[camshaks]

no, there is no backfiring. tuned it up at about 115,000 miles. now when it stalls, it wont start for hours at a time. have to bum a ride home and start it in the morning. somthing is getting hot and keeping it from runnin. i replace the chiny little plastic piece that goes right under the cap. 12 dollar part.

[Rick Norwood]

Originally Posted by camshaks

no, there is no backfiring. tuned it up at about 115,000 miles. now when it stalls, it wont start for hours at a time. have to bum a ride home and start it in the morning. somthing is getting hot and keeping it from runnin. i replace the chiny little plastic piece that goes right under the cap. 12 dollar part.

I think what you are describing is the Rotor.

This sounds more like the distributor module going bad. The older models (pre-1995?) had the module inside of the distributor, but on the newer models it is located outside. Anyway, when the Distributor Module goes bad (at least the older ones) it will do exactly what you are describing. These things are easily tested off of the truck at Autozone. The older ones cost about $35.00

[camshaks]

hey rick is that the same thing as the ignition control module?

[camshaks]

ok rick, i found a shcematic of a distributor for my truck and i see the module. its under the pickup coil. do you suggest replacing the pickup coil too?

[camshaks]

come on guys,please dont let this post die, i really need the help.

[Rick Norwood]

I think you can have the Ignition module checked at Autozone for free. I wouldn't just start replacing everything in a shotgun approach. Have the Ignition Module tested. And yes, My mistake, I believe the real name is the ignition Module. I called it a Distributor Module because it used to be located inside the distributor.

[blazes9395]

For the '98 the ignition control module is located on the passenger side of the engine, just on top of the valve cover. The module in/under the cap is the camshaft sensor. As soon as it dies, thats when you have to check for spark and fuel pressure. My personal opinion on this is that its an ignition problem, maybe a crankshaft position sensor, could be wrong, but you have to test it when its warm and stalled.