Anyone care to help me out with a 2.5 L 4 cyl 92 Chevy S 10

Having some issues with it and just wanting to see if anyone can offer help. S 10 forum sucks real bad. I've taken off the Cat, new fuel pump, fuel press regulator, fuel filter, tps, and tried a new computer as well as map sensor. Also new distri cap and rotor button. It is running a little better but still upon starting up it runs a little rough for about a minute then levels off some. Also put on a new Coolant temp sensor. The Air intake charge sensor looked gummed up and I cleaned it today with carb cleaner just to try something and it ran no different. I'm thinking it's running rich and moreso at startup.

When driving it drives decent but if I take my foot off the gas it will start to buck a little about 5 seconds later. Coming upon a stop or slowing up for a curve it will want to stall out and die if I don't play with the gas. Also notice when its about to do that the brakes feel hard. Also thinking it could be a pickup in the distributor or the Ignition control module. My experiences with pickups is normally a warm issue where car if dies will not want to start back up right away.

With setting the timing on this truck, the manual says to jumper A n B to prevent the control module from trying to advance the timing as you are setting it. Other s 10's have a wire that must be disconnected to accomplish this. I looked up and down left and right upside down and could not find that wire. When I jumper A n B and start the truck, it won't stay running. If I remove the jumper it will run. I tried setting the timing with no jumper and both directions in small increments I set it with a light and got it at its best running at about 12-13 degrees. I don't understand why with the jumper it will die if I jumper it while truck running or if I jumper it then start it doesn't wana stay running.

So basically I'm thinking it has to be something with the pickup, ICM, air intake charge sensor, everything else has been checked and changed. Still not sure those are the culprits but man I'm swamped.

 

Have you checked your vacuum lines for cracking? Sounds like you may have a leak somewhere.

 

yes I used the spray the areas with carb cleaner...........oops was I supposed to use starting fluid?

will double check

 

Not sure I understand. Why would you spray the lines with either one? Just remove and inspect the vacuum lines for cracks or holes.

 

well I've always heard that when spraying if the vehicle's idle changes then for sure you have a vacuum leak in that area but your logic makes sense also so remove and inspect. I guess with vehicle running and if you have an obvious leak where you are spraying then noticing it via idle is just a quicker way to diagnose but yes for the underside of hoses I agree inspecting is better.