O.K., I posted about a week ago about an acceleration problem I was having that I noticed about the same time I changed out my CPS. Here is a more specific description as well as how I have attempted to remedy it.
The 89 4.0 AW4 seemed to have problems accelerating under moderate to heavy pressure on the foot feed. With minimal pressure on the pedal, it will get up to speed. It will cruise at higway speeds o.k. However, on an incline or heavier acceleration, it will start to miss. There are a couple of variations that are interesting. First, the problem is much more noticeable in when it is cold. Second, it seems to be especially noticeable about 1500-2100 r.p.m. In fact, there are points were it will pick up very aggresively; kind of like the power-band on a 2 cycle. Third, I seem to notice it more in 3rd and 4th. Lastly, if i back off the foot feed, it seems that the missing stops fairly quicly; within about 5-10 seconds.
To remedy, I checked the TPS. It was out of adjustment .173 volts; not much but I made sure it was right on the 82%. The reading on the ground as well as the change while moving the throttle were all good. I changed the CPS thinking that I might have had a faulty one. No difference. The injectors are new with only about 10,000 miles on them.
So, any suggestions? Could this be some kind of timing advance issue? Any feedback would be good.
The 89 4.0 AW4 seemed to have problems accelerating under moderate to heavy pressure on the foot feed. With minimal pressure on the pedal, it will get up to speed. It will cruise at higway speeds o.k. However, on an incline or heavier acceleration, it will start to miss. There are a couple of variations that are interesting. First, the problem is much more noticeable in when it is cold. Second, it seems to be especially noticeable about 1500-2100 r.p.m. In fact, there are points were it will pick up very aggresively; kind of like the power-band on a 2 cycle. Third, I seem to notice it more in 3rd and 4th. Lastly, if i back off the foot feed, it seems that the missing stops fairly quicly; within about 5-10 seconds.
To remedy, I checked the TPS. It was out of adjustment .173 volts; not much but I made sure it was right on the 82%. The reading on the ground as well as the change while moving the throttle were all good. I changed the CPS thinking that I might have had a faulty one. No difference. The injectors are new with only about 10,000 miles on them.
So, any suggestions? Could this be some kind of timing advance issue? Any feedback would be good.