02 6speed

- Replaced motor mounts with ES mounts, replaced 02 MAF with 03 AM600 MAF, and reprogrammed/updated ECU at dealership. Recently tuned-up (new sparks, PCV, fluid flushes). Car still bucks hard (will try to get video of this soon so I can show you what I mean). Any ideas on what it could be?

 

When does this "buck" usually happen? My car has a tendency to "buck" in a low gear (1-3) at around 3-4k RPMs when pressing and releasing the throttle. I assumed it was just the late/early/over-estimating/under-estimating drive-by-wire system.

 

is it really bad? These are drive by wire so they are a little lazy i find.
I would try a new throttle body next. Perhaps it is lazy opening and letting air in. Then after you need an aidle air volume relearn again.

 

It is very noticeable in lower gears. I let off the accelerator pedal during smooth, slow acceleration and the car will buck back and forth. For example, 2nd gear, 2-3k RPMs, constant speed, the car will buck forward off the pedal, and will continue to do so during deceleration. If it is the e-throttle, is there any way to smoothen out the signal? I've done all the relearns, but if the car needs to have it reset every so often, it becomes kind of a ridiculous task.

 

Do the IAVL reset and see if it helps.

 

oh so it's ok after relearn for a while and then it shoots banks again?
If so just change the throttle body. Sometimes when we couldn't relearn we just changed the TB and after that it took it like a champ.
I suspect flap does not open smoothly/fast enough. This would be next thing to do....

 

by reprogramming and updating the ECU, you did the NTB03-022 TSB (which deals with hesitation in the 6spds) right?

just making sure.

 

I did the IAVL reset tonight, and will see how it plays out in the next few days.

metalpiotr, I did have that TSB done once I replaced my MAF with the AM600 version.

 

Couldn't that be solved by *very carefully* cleaning it.

Maybe you have a bad ignition coil?

 

You clean the path that the air goes through and the walls not the actualy gear and motor mechanism that opens the trottle body flap.
It may not be necessary a dirt issue but a failed component i suspect

 

I had this happen but only once when I first got my car.
I let it sit over night and it fired up running smooth the next day.

this might be a dumb suggestion, but did you clean the MAF before putting it in?
could have some dust/lint on it from storage?

 

I think its the coils.

adrenaline_rush_fanatic, the MAF was brand new, and even if there was dust/lint sitting there, it wouldn't be for long. The car continues to have hesitation after it starts up, no matter what the temperatures are. I think the word "jerky" as in the car jerks/bucks back and forth is better than the word hesitation.

 

jerky could be due to coils. You should get a misfire code. However it could also be due to a vacum leak. Have you connected the MAF sensor well and tightened all the clamps after the sensor?
Also if the intake plenum gasket was not replaced or installed properly it could leak too
If you bring it in they could check air/fuel mixtures and know if you have a leak. Quite easy for an experienced tech. Bring it in to a different dealer if they can't fix it after all that $$ you put in.

 

I found if i quit the pedal very quickly it doesn't happen. Smooth like silk.

 

I understand what he means by jerky... I had the same bucking bronco once as I indicated. I let the max rest and it didn't do it again. I cleaned MAF when I did oil change as well and it seemed to help
That's great advice!!! Thank you to a helpful member!

 

I think its Driver Error.

 

i got the same problem... i got a set of new coils ready to go in, hopefully thats the problem.

 

I got a set of coils coming in on Thursday. I'll report after that.

Zack, your face is driver error.

 

Is the problem gone?

 

I would look at the Knock Sensor. have you tested it.

 

are you getting any SES codes? any updates on this??