I Really Need Some Help! Screen Shots Inside!
Thread Starter
Launching!
Joined: Mar 2004
Posts: 233
Likes: 0
From: Dallas Texas
I Really Need Some Help! Screen Shots Inside! OK I'm stumped on this issue!
Simptoms:
TPS low activity SES - I show TPS to be 100% working with HPTuners
When WOT car bogs and doesn't want to downshift
TCC goes on and off and sometimes comes on and will not turn off until stop
When problem occurs car doesn't seem to have the same HP as normal
I don't think its really the TPS sensor causing the issue. HpTuners shows its working correctly in the scans. I've also replaced the TPS sensor about a month ago. From what I could find online the TPS low activity basically means that the TP wasn't what the PCM was expecting. So my question is why is expecting some other position? What other sensor is messing up making the PCM expect the wrong TP?
I have scan logs from HPTuners if anyone would like to see it real time!
I attached a couple of screen prints of the problem and 1 of no problem so you can have a reference point.
One Time my MAP sensor got unpluged and it sort of had the same symptoms as this but didn't vary them. Meaning my TCC was always off period and it lacked power and didn't shift right. But this works right like 50% of the time and the other 50% it geeks out and will not downshit correctly and TCC was always off period.
Please Help this is kicking my *** trying find the cause of the problem!
Simptoms:
TPS low activity SES - I show TPS to be 100% working with HPTuners
When WOT car bogs and doesn't want to downshift
TCC goes on and off and sometimes comes on and will not turn off until stop
When problem occurs car doesn't seem to have the same HP as normal
I don't think its really the TPS sensor causing the issue. HpTuners shows its working correctly in the scans. I've also replaced the TPS sensor about a month ago. From what I could find online the TPS low activity basically means that the TP wasn't what the PCM was expecting. So my question is why is expecting some other position? What other sensor is messing up making the PCM expect the wrong TP?
I have scan logs from HPTuners if anyone would like to see it real time!
I attached a couple of screen prints of the problem and 1 of no problem so you can have a reference point.
One Time my MAP sensor got unpluged and it sort of had the same symptoms as this but didn't vary them. Meaning my TCC was always off period and it lacked power and didn't shift right. But this works right like 50% of the time and the other 50% it geeks out and will not downshit correctly and TCC was always off period.
Please Help this is kicking my *** trying find the cause of the problem!
Thread Starter
Launching!
Joined: Mar 2004
Posts: 233
Likes: 0
From: Dallas Texas
Oh almost forgot here is the exact error message!
P0121 - TP Sensor Circuit Insufficient Activity (SES) (Pending) (History) (Immature)
Continuous Tests:
Misfire - Incomplete
Fuel System - Complete
Comprehensive Component - Complete
P0121 - TP Sensor Circuit Insufficient Activity (SES) (Pending) (History) (Immature)
Continuous Tests:
Misfire - Incomplete
Fuel System - Complete
Comprehensive Component - Complete
TECH Senior Member
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
2 things:
The attached pics aren't useful.. too small
and
https://ls1tech.com/forums/search.php?searchid=1317910
I'm about to go to bed so try that search link (I searched P0121)
From the posts I've read.. sounds like it can be easily fixed ...
if that search link doesn't work... then go to search and search for "P0121" ....
The attached pics aren't useful.. too small
and
https://ls1tech.com/forums/search.php?searchid=1317910
I'm about to go to bed so try that search link (I searched P0121)
From the posts I've read.. sounds like it can be easily fixed ...
if that search link doesn't work... then go to search and search for "P0121" ....
Thread Starter
Launching!
Joined: Mar 2004
Posts: 233
Likes: 0
From: Dallas Texas
I'm an Idiot don't know why I didn't do a search with the actual Code instead of by the symtoms I was having!
I found tons of threads about it and solutions to it as well. I'm going to try the doing what the guys with the TREX have done and set the MAP check points 20 higher for both fields. Judging by that thread I would say it will fix my issue. Thanks for setting me straight! I did search first but didn't search the right things!
I found tons of threads about it and solutions to it as well. I'm going to try the doing what the guys with the TREX have done and set the MAP check points 20 higher for both fields. Judging by that thread I would say it will fix my issue. Thanks for setting me straight! I did search first but didn't search the right things!
Let us know if that does the trick and makes the car run right.
Changing the MAP window on the code will only mask the problem I think.
I have the same intermittent problem, and I've seen many other posts about similar wackiness (TCS disarming itself, etc).
This is usually associated with bigger cams, which lower the effective vacuum and skew the MAP, which for some reason horks the TCS and throws TPS codes (P0121).
Various other causes for similar issues (if tuning is known good) are bad grounds in the engine compartment or on the back of the heads, or a bad small AC pressure sending unit (top of the pass side strut tower on the A/C line). That sensor runs on the same +5v circuit as the TPS.
Cheers,
Rob (Bad30th)
Changing the MAP window on the code will only mask the problem I think.
I have the same intermittent problem, and I've seen many other posts about similar wackiness (TCS disarming itself, etc).
This is usually associated with bigger cams, which lower the effective vacuum and skew the MAP, which for some reason horks the TCS and throws TPS codes (P0121).
Various other causes for similar issues (if tuning is known good) are bad grounds in the engine compartment or on the back of the heads, or a bad small AC pressure sending unit (top of the pass side strut tower on the A/C line). That sensor runs on the same +5v circuit as the TPS.
Cheers,
Rob (Bad30th)
Thread Starter
Launching!
Joined: Mar 2004
Posts: 233
Likes: 0
From: Dallas Texas
Well I've only driven it too and from my short trip to work so far today. But thus far it is at least downshifting and no codes and TCC seems to function correctly again. I'm not 100% for sure it is up shifting at the RPM that I set in HPTuners, but I will confirm that a little bit later today when the streets dry off a little so the car doesn't try to slide out from under me! LOL. It is definatly a major improvment that is 100% for sure!! I'll post another udate later when I can get some WOT feedback. Thanks for the help! Much appreciated this was P.O me for over a month now.
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TECH Fanatic
iTrader: (3)
Joined: Mar 2003
Posts: 1,162
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From: Bensalem, Pa, now montreal, Quebec
how come your o2s switch so fast? like they switch at the same time! my graphs look horrible compared to that, they arent close only at WOT they are kinda close, but normal driving, one can be at .700 and the other .200, but yours seem to switch at the same time? is everyones like that?