Transmission issues/slow take off

[jevans106]

Greetings all,

I have been struggling with either a transmission or engine problem for a while now on my 95 G20.
Here is the issue and what I have replaced:
1st gear/take off is slow and sluggish (reverse is fine), once the transmission shifts out of 1st gear, transmission seems fine. You basically have to floor it for take off. I have replaced the shift or drop sensor and changed the fluid with no affect. Apparently there is a vacuum module somewhere on the transmission. If anyone knows about, please let me know so I can get the part. I herd this might be the problem. Other than this, I have no clue, if 1st gear was out, reverse would also be out and it is fine.


Thanks,
Justin

[ENO]

im guessin its a AT???










































theres your problem.....lol , sorry i cant help but good luck

[{-_-}]

Does the car run fine otherwise?

I was having similar issues but the car ran like crap and lacked power as well. It turned out to be fuel problem.

[jevans106]

Does the car run fine otherwise?

I was having similar issues but the car ran like crap and lacked power as well. It turned out to be fuel problem.

Yes the car runs fine otherwise and it is a AT.

justin

[2000ET1G20]

Have you checked the battery? Low battery voltage could wreak havoc on a TCM.

Happened to my in my P11, battery was bad, was having hard start issues and when driving it would start out in 3rd gear from a dead stop. Not even mashing the gas to the floor would do anything until i got up to speed then it seemed fine.

I changed the fluid and nothing. Then i looked at the FSM and it said battery voltage below minimum will cause trans. shifting issues. I changed the battery and not a peep since.

[jevans106]

Have you checked the battery? Low battery voltage could wreak havoc on a TCM.

Happened to my in my P11, battery was bad, was having hard start issues and when driving it would start out in 3rd gear from a dead stop. Not even mashing the gas to the floor would do anything until i got up to speed then it seemed fine.

I changed the fluid and nothing. Then i looked at the FSM and it said battery voltage below minimum will cause trans. shifting issues. I changed the battery and not a peep since.

Battery is good and faily new, I had a Omptima installed last year. Had same problem beofore the battery was changed. Could it be some sensor?

justin

[hypesteez]

yeah man i have same problem like it takes off really slow but then when u floor it mine goes high rpm like the idle goes to the redline and then drops all of the sudden AND sometimes when my car shifts it goes high RPM then when it shifts it jerks, it wierd cuz sometimes im not even flooring it but then my car jerks when it changes gear and it goes high RPM. so yeah it would be nice to help this guy! i wanna get some answers too.

[jevans106]

yeah man i have same problem like it takes off really slow but then when u floor it mine goes high rpm like the idle goes to the redline and then drops all of the sudden AND sometimes when my car shifts it goes high RPM then when it shifts it jerks, it wierd cuz sometimes im not even flooring it but then my car jerks when it changes gear and it goes high RPM. so yeah it would be nice to help this guy! i wanna get some answers too.

I know, it sux,
I do not have much of a jerk in the transmission shifting, it does jerk a little. really sux on take off. Get this, I have a hho (hydrogen) kit installed just to keep it running right.
Infinity here, will charge me $150 just to tell me I might have computer issues, another words, they do not know and I do not have the money to spend on guesses again. I already spent too much at infinity for nothing.
This seems to be a know problem if both of us have almost identical problems, so someone knows about it. I had a code that said a knock sensor was out, yet I could not get it off to replace. Not sure if it would make a difference anyways when I had codes checked. I do not believe the codes since it also said I had second gear out on the transmission, second gear is fine. If any gear is out, I would suspect first however, I suspect a sensor controlling efi functions is out o some sort of speed control on the transmission rather than a second gear and knock sensor issue.

Justin

[g20kdgirl]

It's your knock sensor. My 95 was the same way. replaced and car works fine. It's not easy to replace due to its poor location.

[thunder storm]

also, check your grounds. couldn't hurt to re-ground the tranny, to make sure it's not a power issue.

[JLWOLD]

or, a, maybe buy my 5speed? complete swap!
lol, goodluck with figuring this out, it's been sooo long since i've owned an automatic that i wouldn't know where to start on issues like this.

[jevans106]

Greetings, how did you get the knock sensor off? I tried everything, I am getting ready to change out the exhuast with headers, I should have more space to get to the sensor. Since my exuast was never changed out, I suspect the cat and muffler is history as well. I am also replacing the CIA.

Cheers,
Justin

[jevans106]

Greetings,

how did you get the knock sensor off, last time I remembered I could not get a tool on the bolt and or room enough to turn a tool? I tried everything, at that time and now the bolt is history. I am getting ready to change out the exhuast with headers, I should have more space to get to the sensor. Since my exuast was never changed out, I suspect the cat and muffler is history as well. I am also replacing the CAI.

Cheers,
Justin

[Plat-num]

i'm having almost the same problem without any jerking.
i don't have 1st gear as well. but yesterday it was running fine.
had a code from the other week that said rear O2 sensor bank 1 high voltage.

i'm going to check the transmission wiring by disconnecting them and re connecting them. i'm hoping that there is just a bad connection.
tested my battery and it came out good. i was hoping that was the problem.

[jevans106]

i'm having almost the same problem without any jerking.
i don't have 1st gear as well. but yesterday it was running fine.
had a code from the other week that said rear O2 sensor bank 1 high voltage.

i'm going to check the transmission wiring by disconnecting them and re connecting them. i'm hoping that there is just a bad connection.
tested my battery and it came out good. i was hoping that was the problem.

Keep me posted,
I am still not convinced it is the transmission. The one guy said it was the knock sensor and the knock sensor is throwing that code.
If the sensor and exuast does not do the trick, I am done and will just drive it until I trade it in. I am lucky if I get 250 miles to a tank of gas.
I will check the tranny connections when I am all up in it this weekend.

Justin

[Plat-num]

i'm probably not going to have time till tomorrow or sunday.
hope our problems get solved

[jevans106]

i'm probably not going to have time till tomorrow or sunday.
hope our problems get solved

Greetings,
here is an update,
I did not get all my parts on time. I installed the headers, cai and cat, could not get the knock sensor bolt out. I am getting the knock sensor replaced friday and the old sensor is history.
The car is running better and it seems some of the problems was solved.
I will know more in a couple of weeks when I get my knock sensor and muffler in.

Justin

[jevans106]

Final update,

Added new muffler, spark plugs and knock sensor. The car runs better and almost new at times. However, there is still some sensor or module out. I am honestly giving up since I am at a lost on how a car can run fine at one moment and fail the next in the same conditions. I have often thought that this might be a throttle sensor issue which would make sense since at times the car would be lean on take off thus lagging on take off.
I am not sure it is a MFA sensor and does not seem to be since I added in a HHO module that tapped into the MFA. I took the module out and found out how the MFA worked when it was modified. This brings me back to either another intake sensor or throttle.

Justin

[jevans106]

i'm having almost the same problem without any jerking.
i don't have 1st gear as well. but yesterday it was running fine.
had a code from the other week that said rear O2 sensor bank 1 high voltage.

i'm going to check the transmission wiring by disconnecting them and re connecting them. i'm hoping that there is just a bad connection.
tested my battery and it came out good. i was hoping that was the problem.

Final update,

Added new muffler, spark plugs and knock sensor. The car runs better and almost new at times. However, there is still some sensor or module out. I am honestly giving up since I am at a lost on how a car can run fine at one moment and fail the next in the same conditions. I have often thought that this might be a throttle sensor issue which would make sense since at times the car would be lean on take off thus lagging on take off.
I am not sure it is a MFA sensor and does not seem to be since I added in a HHO module that tapped into the MFA. I took the module out and found out how the MFA worked when it was modified. This brings me back to either another intake sensor or throttle.