Thread: 2005 rpm going up and down

hello, i posted a couple of days agao about having issues with my grand prix, and how i was having problems with the rpms going up and down while the car was in motion. and when the car takes off or is getting ready to shift it seems that the car will make this huge jerk and go, so i had the mechanic look at it and said that it was the transmission in the car, so i replaced the trans with a used trans, but know the car almost at everytime of a take off from a light or a stop will make this huge jerk move before going ahead up the street, does anyone have any clue what this issue is?

I am new to this site and have an extremely limited knowledge of the GP.....however, a friend of mine was having a similar problem with his dodge truck and a local transmission company told him the same thing. Same outcome as yours. In the end, it was a faulty transmission module (brain) that was the culprit. Hope this helps.

so did they put another trans in it or what happende in this sitution?

yeha the mechanic toped off all fluids for the car, the strange thing about this is that this issue was not even doing this when i took the car in, i had some jerks here in there while the car was moving back and forth to my destenations, and the rpm problem, but since this used trans has been put in almost at everystop of a light or anything once i i go on the gas i get this huge jerk almost everytime, i will take alook at this link, i let u know after reading, thanks

jamal313,

It is difficult to say. A few suggestions are an issue with the valve box in the transmission; another could be the mass airflow sensor. These are just suggestions, it is not a diagnosis. It would be best to take the vehicle in to be inspected by a certified technician.

Please keep us posted.

If you have additional questions, please feel free to contact me.

Louis
GM Customer Service

yes i do have a question, im in belleville michigan and would like to know were i could take the car for a thural check of this issue, and how would i be able to contact you

well he ijust put a used trans in, i had the mechanic checking the mounts and he said that they were good, and i will ask him about the bolt issue and its a bang, so i stop at the light and when i take off, its a huge jerk then goes