eec-iv woes

[AlaskanRider]

Hello.
I recently completed an 4.0 engine swap and am having trouble with getting it to run well. Initially I had a funky idle with and the engine would buck and lug with any sort of acceleration. It seemed to be not quite as bad above 2500 rpm as below 2500.

Motor is from a wrecked 91 ranger extended cab, 71,000 miles. It did alot of sitting as a wreck though.

Pulled some codes, which told me that I had a bad MAP, a bad ECT, and a lean condition. It also gave me the codes associated with using an auto computer on a manual transmission.

So replaced the ECT, and used the MAP from my b2. I also added some injector cleaner, just because the injectors have been sitting so long. Idle is a little smoother, but it still lugs and bucks when you do anything more than a light cruise.

Will pull codes again later, but I'm a little stumped as to how little effect replacing this stuff had on the problem.

Any ideas? I did pull the negative battery cable for 30 minutes or so, to reset the computer as I replaced the sensors.

Haven't checked fuel pressure yet.

My last motor also ran lean, and wouldn't lug but would ping like crazy.

 

[AlaskanRider]

Update.
Got a new code, for bad IAT, so I replaced that and now there are engine codes. I also replaced my vacuum lines, because it was cheap &easy and I wanted to eliminate the possibility of them leaking.

Problem is that it still lugs and bucks and shakes like crazy, it has seemed to improve though. When open it up, its fine, but at cruise and light acceleration, it lugs, bucks, and misses.

Idle it better, it doesn't miss like it used to, although it still will hunt and stall and shake the whole truck occasionally.

It is usually fine right after I start it but within a couple minutes or if I drive it 200 ft the issues start.

Do bad 02 sensors ever cause this?

Will check compression and fuel pressure next.

 

[AlaskanRider]

Ok, I got it figured out. I replaced plugs, wires and 02 sensor and now it runs great. One of the plugs looked darker than the rest, and had gas on it, so I think it or its wire was bad.

Still got a little funky idle, but I am running the auto computer, and this engine did 10 or 15 years of sitting. I'm totally satisfied with it, as long as it doesn't lug or stall when it idle.