Welcome Visitor! Please take a few seconds and I have been using the truck for several months and it ran okay but not great. One day it started to buck and bog with moderate throttle, limped the truck home. Looking around under the hood found a vacuum leak and fixed it (the truck did have a high idle).
Thinking the IAC was the issue I unplugged it while warm and the truck would run smooth and only needed the slightest throttle input to keep from stalling out. The odd part is the truck will not run unless the IAC is unplugged, even with this the truck can move far. If the engine is cold the truck will not start unless the IAC is unplugged.
I have tried taking the leads off the battery and touching them together for about 3 mins to clear the computer. No difference seen.
1. Truck will not run unless IAC is unplugged (warm and cold). A new IAC sees no difference in performance. Truck revs up great and smooth with IAC unplugged.
2. IAC plugged in the truck will crank with what appears to be zero effort in starting.
Any advice on what the issue could be or tests to run?
The vacuum leak was a hose disconnected at the vacuum tank below the air box. Also next to the starter solenoid is what looks like a vacuum solenoid with a missing hose on the red port. This solenoid also seems to buzz after key off.
1987 STX
2.9
4x4
Thinking the IAC was the issue I unplugged it while warm and the truck would run smooth and only needed the slightest throttle input to keep from stalling out. The odd part is the truck will not run unless the IAC is unplugged, even with this the truck can move far. If the engine is cold the truck will not start unless the IAC is unplugged.
I have tried taking the leads off the battery and touching them together for about 3 mins to clear the computer. No difference seen.
1. Truck will not run unless IAC is unplugged (warm and cold). A new IAC sees no difference in performance. Truck revs up great and smooth with IAC unplugged.
2. IAC plugged in the truck will crank with what appears to be zero effort in starting.
Any advice on what the issue could be or tests to run?
The vacuum leak was a hose disconnected at the vacuum tank below the air box. Also next to the starter solenoid is what looks like a vacuum solenoid with a missing hose on the red port. This solenoid also seems to buzz after key off.
1987 STX
2.9
4x4
