Explorer Bucking!

[BadAzzexplr]

Hi I have a 1997 ford explorer 5.0. I recently had the dealer replaced the exhaust manifold and since then all hell as broken loose. my truck stutters when starting off and between 50 & 55 on the highway. I had ford do a power balance test and the plugs & wires are fine, as well as the coil pack.

We just replaced the TPS (throtte posistion switch & Fuel filter). The truck still is stuttering under a load. What else can I do. I was thinking maybe cleaning the Mass air flow sensor. , but at this point its just guess work.

Any Ideas.

 

[tbomb]

ive been sitting here doing work for the last 6 hours, so my brain is a little shot right now, but maybe a clogged fuel filter, though, that wouldnt just cause the problem at startup and 55 mph, but at least now you got something else to think about

 

[BadAzzexplr]

Tbomb, thanks for the reply. I had replaced the fuel filter the other day when i did the TPS.

 

[oahrens]

Cleaning the MAS couldn't hurt and make sure to reset the computer. "I recently had the dealer replaced the exhaust manifold and since then all hell as broken loose." Why haven't you returned to the dealer and demand repair? :smoke:

 

[Anime]

exhaust

Well, my guess is....the exhaust.

I just did the whole clutch job and tranny thing awhile ago, and to do it the Y-pipe has to be removed with the exhaust. Afterwards and since, I've had a number of funny problems, from check engine lights to random "bucking" at 45-65 or so.

It must be one small leak from where the manifold meets the Y-pipes on each side, but apparently it is enough to cause a problem. I suggest following oahrens advice and take it back to where you had the work done, and tell them to check for a leak or just redo the whole thing- and do it right this time.

 

[BadAzzexplr]

Ok I did bring back to the dealer. They are say its a new problem. They had me do a power balance test & then we replaced the tps sensor & fuel filter.

I have told them the problem was related to the exhaust changing, but they disagree. So I am in a bind where I need this fixed and they are the only ones who can do it. Also I am out of warranty so now, its getting very costly at $90 an hour!

 

[Alec]

A minor exhaust leak shouldn't cause a bucking problem. You may loose a bit of power, but no biggie. However, when they messed with the exhaust, they could've messed up the O2 sensors. Just a suggestion.

 

[BadAzzexplr]

What about the EGR valve? Could that be a problem. Or is that the O2 sensor.

 

[Alec]

No, EGR is different than the O2 sensors. That could definately be the problem also. Silly me for not thinking of that