No acceleration

EAWSTYLE

MEMBER
2006 INFINITI M35
6 CYL
4WD
AUTOMATIC
130,000 MILES

The had the transmission ECU replaced, took vehicle for test drive everything well. As we returned from test drive no acceleration. Replaced throttle body, pedal with sensors. Took to dealer and at 4 hrs they said it was the transmission ECU. Had the original ECU repaired and tested out. Issue continued. When the car is placed in gear, no codes, all other aspects of the car function well. Not sure where to look next.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

We are going to need to get a little more info for this and go from there.

When you say it will not accelerate, does the RPMs go up like it is in Neutral or does it not respond at all?

Are there any noises like grinding when you are accelerating?

When you say there are no codes, have you had the vehicle scanned by a different scan tool or did the dealer tell you there are no codes? I just find it hard to believe that we have no codes and no acceleration.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

So, if we have no codes then we need to use a scan tool to monitor the gear selected in the PCM and make sure it is seeing the vehicle go into gear.

On this transmission you have a manual valve that moves the control valve in the TCM to tell it is in gear. However, if the TCM is not seeing it go into gear then that could be the issue.

Lastly, do you have the part number of this module that you replaced because there are many names for the transmission ECU and I want to make sure we are talking about the same thing.

Thanks

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