I just bought this 88 with a 2.0 and it has a carb. The truck is really clean and seems taken care of and rolled off the lot of the local shyster without a hitch. Truck runs down the highway good and seems to fire up ok for having 125,000 on the clock. Well the other day it was running fine down the highway and it flashed a check engine light for a few seconds and fell on its face. The light went out and back to normal I go. It did that 2 or three times over 2 days. I tried doing the jumper wire deal to see if it pitched a code and nothing showed up. This morning it fired up and I ran it 40 miles to my work. When I pulled into my space it stalled out. Now its having a rough idle like it is missing or the idle speed is way to low. I checked around and found to little vac leaks from old hoses but they do not solve the problem when fixed. It seems like the idle slowly drops lower and lower until it stalls. But it will fire right back up. I am new to computers and sensors telling my truck what to do, so if anyone wants to point me in a direction to check that would be great. I am clueless when it comes to emission stuff so its all greek to me. Sorry about the long post.

 

I see you don't have any replys, so i'll see if I can get things started.

If the CEL came on, there should be at least a pending code stored in the computer & any trouble code Numbers can be helpful in your trouble shoot, so maybe call around & see if any of your autoparts stores can scan your OBD-1 system. Many stores in my area use the Actron CP9145 scantool with the proper hook up cable to scan Ford, Chrysler & GM OBD-1 vehicles.

That said, seeing as how it runs, just intermittently acts out, it's probably a spark, or fuel delivery problem.

So, maybe begin your trouble shoot with a fuel pressure check. Fuel pump, fuel pressure regulator, clogged fuel filter, sticking carb float, wrong float height adjustment, water/ice in the float bowl should be on your suspect list.

On the spark system check, raise the hood at night & look for arcs & sparks & maybe do a secondary ignition wet down test with a spray bottle of water, all the way from the coil along each plug wire to the spark plug, looking for arcs & sparks, or rough idle.

Some thoughts for consideration, let us know how it goes.

 

I spent some time searching the vac lines and found one more broken line. After fixing that the idle is a bit smoother and its not stalling anymore. The idle still seems to low though. It will studder and miss still at idle, and then clear up for a few seconds so that it surges up a few hundred RPM. The cap and rotor was fair so I will probably just replace it and wires as I have no clue when they were done last. When I last filled it I dumped a can of sea foam in the tank, so I am wondering if that might becausing me some sensor grief or something. The check engine light situation has yet to show back up. Thanks for any help or ideas