HELP!!!! Major loping and idle issues.

[ranger rob]

I have an 87 with a 2.9. It has typically been a great truck. Lately it has been issue after issue. I recently had to replace the distributor in response to a faulty hall effect switch. In the process of chasing down possibilities I checked the fuel filters and replaced the in line filter and installed a canister type filter. There wasn't even one in it! I put on a new cap and rotor as well as a new ignition control module. Once I dropped the new distributor in place everything was awesome.

Now not so much. I've only put about 3000 miles on since the distributor issue. Currently I'm dealing with loping and idle issues. It will still run, but I have to give it some throttle to get it to move. When coming from a dead stop, it has no throttle sometimes. I have to put my foot in it to get it up to decent rpms. Once at higher speed it seems to run decent, but at a lower speed it lopes and bucks like I'm hitting the brakes or the clutch.

Here is a list of things i've done.
-replaced plugs and wires
-checked and replaced throttle position sensor with an old used one
-pulled egr valve from plenum to clean it, but didn't get very far. couldnt get it off the exhaust tube. cleaned what i could get at.
-plugged egr entrance into plenum with no real change.
-checked fuel pressure, no issue
-checked map sensor, no issue
-pulled off rusty old exhaust muffler, no change, but it's louder!
-poured a bottle of seafoam in, no change
-checked ignition control module, no issues
-pulled the battery cables off to see if that does anything, now it barely runs.

I'm stumped!!! I could really use some help with this! Thanks!

 

[IMenriched]

I have an 87 with a 2.9. It has typically been a great truck. Lately it has been issue after issue. I recently had to replace the distributor in response to a faulty hall effect switch. In the process of chasing down possibilities I checked the fuel filters and replaced the in line filter and installed a canister type filter. There wasn't even one in it! I put on a new cap and rotor as well as a new ignition control module. Once I dropped the new distributor in place everything was awesome.

Now not so much. I've only put about 3000 miles on since the distributor issue. Currently I'm dealing with loping and idle issues. It will still run, but I have to give it some throttle to get it to move. When coming from a dead stop, it has no throttle sometimes. I have to put my foot in it to get it up to decent rpms. Once at higher speed it seems to run decent, but at a lower speed it lopes and bucks like I'm hitting the brakes or the clutch.

Here is a list of things i've done.
-replaced plugs and wires
-checked and replaced throttle position sensor with an old used one
-pulled egr valve from plenum to clean it, but didn't get very far. couldnt get it off the exhaust tube. cleaned what i could get at.
-plugged egr entrance into plenum with no real change.
-checked fuel pressure, no issue
-checked map sensor, no issue
-pulled off rusty old exhaust muffler, no change, but it's louder!
-poured a bottle of seafoam in, no change
-checked ignition control module, no issues
-pulled the battery cables off to see if that does anything, now it barely runs.

I'm stumped!!! I could really use some help with this

Have you tried to get codes?
but seems like the AIC could stand a good cleaning

 

[Cyberbeer]

There should not be a filter in that canister. Remove the filter from the canister and that will probably fix your problems. If you cant get the canister to reseal then you will have to buy a new one from Ford. In 87 they did away with the canister filter but left the canister and switched to in line types.

More then likely the canister is seeping fuel. I had a similiar problem on my own 87. Took the old canister out put a new one in, cracked the old one and someone had put a filter in it. Due to the design the filter more or less floats because the 86 and 87 canisters are slightly different.

 

[holyford86]

Pull codes, pull and clean your IAC, test the TPS by backprobing the center pin on the connector with an ANALOG voltmeter, slowly open the throttle (key on engine off) watch for a steady increase in voltage without any flat or dead spots, if there are the TPS is bad.