Ok so to start off I just finished rebuilding my 2.8l in my 87 s10 blazer! Not what I wanted but needed something until I can afford the motor I want! It stalls out after its warmed up! When I first start it and it's cold it sounds like it has a cam for about 5-10 sec then idles up! Runs fine till its to running temp! Then if I turn the wheel till it hits the bump stop it will die! When I drive and come to a stop it dies! It has a new dizzy and I cleaned the iac but still no luck! It's very frustraiting and I would like to get it fix! I've got a whole not her motor with all the sensors! I'm goin to switch sensors one by one and hope that fixes it! Another thing is when I bought it the coolant temp sender was removed and a manual gauge installed! Idk if that would effect it! Any suggestions would be greatly appreciated! If u need any more info I can give it! It has no check engine light either!!! Plz help

 

check for vacum leaks

 

Urg!! i cant remember the name of the sensor but it controls the engine RPM when accessories are being used like power steering. So if thats not working properly then your engine will die if you put a load like that on it. But thats just my guess as to what it is and me not being able to remember the name doesnt really help so hopefully someone will..

 

I have checked for vac leaks and haven't found any yet! And are u talking about the throttle possision sensor, idle air control, um I can't think of the others right now!

 

Iac valve. +1 for me! lol

is your 87 fuel injected or carburetor? if its fuel injected could be a weak pump,as they are notorious for getting weak or going out in these trucks.

 

Ya it's tbi! I haven't checked the fuel pressure but I didn't really consider that sense it idles and drives fine until it warms up! But that's something I need to check on! How much psi should it have at idle, drive and stopped (under load)?

 

10-13 psi. You need a special adapter to check the pressure. your local autozone MIGHT have it in the fuel pressure kit they loan out,im not sure. If it turns out to be the pump only! buy a ac delco pump. These things hate aftermarket pumps. You can find the ac delco pump only from rock auto,amazon etc for less then 50 bucks,which is the same cost as a after market. i think i paid like 79 for mine at the dealership.

 

Ok I haven't check the fuel yet but I replaced the radiator cuz It was clogged enough to make it run hotter then normal! Fixed that problem and it ran a lot better! I noticed when I was checking my vacuum lines again the the vacuum line that comes out of the front of the throttle body and goes to the map sensor was melted closed! Replaced it and bam, it starts up almost perfect! It doesn't die as much but still every once in a while! I put 5w30 synthetic oil in it when I finished the rebuild, I think this is what's making it die because the oil pressure goes way down at idle! I think the dummy switch is killing it cuz it thinks it's got no pressure! I'm goin to run a thicker non synthetic oil with some Lucas and see if that helps! I'll let y'all know! Thanks

 

the idle could be to low. some tbodies have a set screw to odle them up. i have found if the timing is off it will die to.

 

i had an 87, with a similar issue, i too replaced the distributor, however, one day when angry and ready to hulk smash everything under the hood i bumped the distributor and she started running normal. what started my issue was when i let her overheat one day she would sound like she had a cam (bump and stump while warming up). SO after bumping the distributor, i replaced it, still same problem, well upon hooking up a fancy scan tool (thanks dad) i noticed (dad said something about it) that the icm was acting funny, that little sensor mounted under the distributor. Well replaced that sensor and it ran fine for a bit, then it did it all over again, well after buying the third icm i noticed that this one came with a little packet of some neato grease. I asked the guy behind the counter (he was around when they invented internal combustion) he said it helps to dissapate heat from the icm, oh wow i said, he took a look at my old sensor(called me an idiot, oh well) and said "ear be ya poblem, youse ain't ben usin none uh de goo"

Anyways, upon further research come to find out that grease dries up easy, once it dries up it's difficult for the icm to dissipate that heat as fast as it needs to and when the icm gets too hot it will shut the motor down. I applied the grease, put this icm back on and it worked ever since (until the day hurricane irene came). Just a thought, apparently the guys that make minimum wage building these distributors sometimes forget to put the grease on the icm.