Trouble with 1990 B2 - Poor acceleration

[jhurt1976]

I'm stumped as to what to do now. I have a 1990 B2 that I've been working on. Just replaced the fuel pump, fuel filter, plugs, wires, dist. cap, distributor, catalytic converter and injectors and it still has a rough idle and acceleration. Seems to run better when it's warm outside but at night time I can't even keep highway speeds. Not sure what else to check.

 

[Big Jim M]

Jhurt Not quite enough to go on here.. Give some particulars! How does it run? Does it cough and spit? Does it Make noises? Does it run at low speeds well? C'mon tell us what it does and when?
Big JIm

 

[jhurt1976]

Yes, it coughs and spits a lot, especially when it's at night and the block is really cool. Checked for vacuum leaks and couldn't find any. When I press down on the gas pedal it speeds up really slow (or slows down if I'm going up an incline, just bogs down on me). Runs really bad at low speeds and no unusual noises that I can hear other than some vibration when it bogs down on me when I start to move.

Went out to see how it ran now that it's daylight and nice and warm out, it still bogs down some but not to the point that it vibrates really bad when starting out. Still definitely noticeable though, probably about 50% better than when starting it up at night time.

 

[90B24wd]

Did you check your timing? Also, be sure to remove you spout plug when setting it.

 

[jhurt1976]

Yeah, timing was set at the shop when they changed out the distributor. I took the breather hose off too and smelled it for exhaust. It kind of smelled faint so not sure if the exhaust is backing up or not, haven't replaced the muffler yet. Someone said that a new catalytic converter can make it run rough until you put 50-100 miles on it and get it heated up really good but I'm afraid if I drive it I might mess something else up.

 

[IMenriched]

get the codes...1st and see what they're telling you....check with your local/favorite parts store maybe they'll read them for you.

 

[90B24wd]

"Yeah, timing was set at the shop when they changed out the distributor."

But was the spout plug removed when the timing set?

 

[jhurt1976]

Not sure if they removed the spout plug. I took it to Pepboys to get the distributor changed out. I called them today and I'm supposed to take it back in since they had run a diagnostic before the distributor change out. Will post on what they say and see if it makes sense to y'all (I know little about this kind of stuff).

 

[jhurt1976]

Diagnostic done, they say it's my ECM causing the engine to fire incorrectly.

 

[WhiteBroncoII2WD]

Diagnostic done, they say it's my ECM causing the engine to fire incorrectly.

Was the truck having problems before the distributor change?

 

[jhurt1976]

Yep yep, it sure was