Brand new TPS not reading correctly?
06-06-2016, 07:18 AM
#1
TECH Apprentice
Thread Starter
iTrader: (5)
Join Date: Jul 2010
Location: Pasadena, Maryland
Posts: 320
Likes: 0
Received 0 Likes
on
0 Posts
Brand new TPS not reading correctly? Hey guys, a little background is that my cars TPS began to read 14% when the blade was shut and doing the relearn would only fix it for that drive. The voltages still read correctly at .5v idle and mid 4.xv WOT. So I went ahead and bought a new AC Delco TPS and it still is giving me the same issue after the relearn. Did I get that unlucky and get a bad one out of the box? The new sensors voltages are ever so slightly different, but marginal compared to the old one.
06-06-2016, 03:31 PM
#2
I'm having the same issue with mine. Showing TPS .55v at idle and 0.0% TPS with 15 IAC at 133*F coolant temp. After getting to 176*F coolant temp my TPS .57v at idle and 13.7% TPS with 70 IAC counts. So now my 600 comanded idle is 800 when the TPS starts getting screwy.
I wouldnt think ACdelco being bad out of the box.
Interested to see what you come up with/fix it.
I wouldnt think ACdelco being bad out of the box.
Interested to see what you come up with/fix it.
06-07-2016, 06:38 AM
#3
TECH Apprentice
Thread Starter
iTrader: (5)
Join Date: Jul 2010
Location: Pasadena, Maryland
Posts: 320
Likes: 0
Received 0 Likes
on
0 Posts
Yeah I'm not sure what is going on, it was fine and then all of the sudden it got weird so I just assumed the old sensor was having issues and replacing would fix it.
06-10-2016, 07:13 PM
#5
TECH Apprentice
Thread Starter
iTrader: (5)
Join Date: Jul 2010
Location: Pasadena, Maryland
Posts: 320
Likes: 0
Received 0 Likes
on
0 Posts
I pulled my codes and got P0122 and P1122 which both point to low voltage. However with the car just on and not running it reads normal. It seems to be getting more persistent and the TPS relearn doesn't fix the issue. I'm thinking its wiring.
06-10-2016, 07:41 PM
#6
Low voltage as the TPS is recieving low voltage or putting out low voltage. What's the charging battery state sitting and running?
06-10-2016, 09:50 PM
#7
I'd love to know if you find the answer and it ends up being wiring. I'm having p0122 intermittently as well. After I cleared the codes and did the relearn, the code wasn't there, but ice yet to start the car. I will tomorrow and we'll see. Also have a new sensor waiting to be installed.
Trending Topics
06-11-2016, 11:28 AM
#8
TECH Apprentice
Thread Starter
iTrader: (5)
Join Date: Jul 2010
Location: Pasadena, Maryland
Posts: 320
Likes: 0
Received 0 Likes
on
0 Posts
Mine will do it on a cold start, and its an intermittent problem. I did the relearn again yesterday, still was happening. Backed it out of the garage and shut it off, turned it right back on and it was idling normally. I have no idea what's going on because with the car running it reads the TPS percentage and voltage just fine but when it goes into closed loop it reads it as 14% open but voltage stays normal.
06-14-2016, 10:10 AM
#12
TECH Apprentice
Thread Starter
iTrader: (5)
Join Date: Jul 2010
Location: Pasadena, Maryland
Posts: 320
Likes: 0
Received 0 Likes
on
0 Posts
Yeah I did the relearn procedure of unplugging it, turn the car to on for 5 seconds, shut car off, and plug it back in. I checked and if the cable was getting hung up the voltage would rise as well, but the voltage is steady until I actually move the throttle. I noticed also that the car reads the TPS properly when turned to on, but while running is when it seems to act up.
06-15-2016, 11:22 AM
#13
I think the relearn process is more than 5s. I think the correct way is unplug, turn car on (not running) for 30s, shut off and plug back in. Thats what Ive read.
I ended up swapping the new AC delco TPS on mine already but haven't started it. My testing of the TPS voltage shows it at .51v where as the original one was .55v with no gas in resting position. Full voltage is also only in the 4.3v range. TPS % is at 0% with engine off and rises to 100% at 4.3v and WOT. I have yet to start it as ripped off my FMIC and increased my meth injection and doing wiring/gauges. I should be able to hopefully drive it friday and get some actual hot engine info for you. I did also decide to clean the heck out of the TB, Esp the IAC area and sprayed the sensor down alittle. I also purchased a cheap IAC sensor like $12 to test if the problem continues... AC delco IAC sensor is like $100!!!
My original sensor seemed fine tho as well and it only acted up when warm. I did notice that my IAC count was 15ish at hot idle with TPS .55v and 0% TPS, but when TPS was at 14% IAC was like 69counts, TPS voltage was .55-.58v which is normal. So I have the same issue as the OP, only when hot did mine become an issue and raise idle rpm like 100-200rpms. However mine is set in Open loop, as I think closed loop with yours is just proof that your engine temp reaches the 131*F setting (warm engine) where the heat affects the TPS sensor.
Ive also verified full throttle closing by giving the car quick throttle and I can hear the TB tap closed when the issue arises. Since voltage doesn't increase and the TPS % does it must be something between the TPS sensor and the PCM.
I ended up swapping the new AC delco TPS on mine already but haven't started it. My testing of the TPS voltage shows it at .51v where as the original one was .55v with no gas in resting position. Full voltage is also only in the 4.3v range. TPS % is at 0% with engine off and rises to 100% at 4.3v and WOT. I have yet to start it as ripped off my FMIC and increased my meth injection and doing wiring/gauges. I should be able to hopefully drive it friday and get some actual hot engine info for you. I did also decide to clean the heck out of the TB, Esp the IAC area and sprayed the sensor down alittle. I also purchased a cheap IAC sensor like $12 to test if the problem continues... AC delco IAC sensor is like $100!!!
My original sensor seemed fine tho as well and it only acted up when warm. I did notice that my IAC count was 15ish at hot idle with TPS .55v and 0% TPS, but when TPS was at 14% IAC was like 69counts, TPS voltage was .55-.58v which is normal. So I have the same issue as the OP, only when hot did mine become an issue and raise idle rpm like 100-200rpms. However mine is set in Open loop, as I think closed loop with yours is just proof that your engine temp reaches the 131*F setting (warm engine) where the heat affects the TPS sensor.
Ive also verified full throttle closing by giving the car quick throttle and I can hear the TB tap closed when the issue arises. Since voltage doesn't increase and the TPS % does it must be something between the TPS sensor and the PCM.
06-16-2016, 07:46 AM
#14
TECH Apprentice
Thread Starter
iTrader: (5)
Join Date: Jul 2010
Location: Pasadena, Maryland
Posts: 320
Likes: 0
Received 0 Likes
on
0 Posts
I'll give the longer relearn a shot, I'm taking the car to Carlisle Saturday either way, it would just be nice to not have a high idle driving there.
06-17-2016, 02:35 PM
#15
Nice, Carlisle is a nice show... I sometimes go in august for the vette show with my dad and brother. Never get up their for GM shows lol.
Well it seems the new TPS sensor fixed my issue. Had it up to temp and put a lot of driving on it... most thus far. cold motor Key on TPS voltage = .51v, 0% TPS. hot idle 176-180*F TPS = .51-.53v and 0-.4 TPS %. IT never changed it was always 0% to .4% and my idle stayed rock solid at 600.
The only change I made besides the new TPS is I cleaned the IAC and TB a lot. I also removed the FMIC which caused much higher engine temps like 190-200*F which might have aggravated the TPS% issue. With the FMIC gone I run 174-180*F all day.
maybe u got a bad one? Have you checked the TPS plug? maybe see if it has enough slack? maybe you need to lower engine temps lol.
Well it seems the new TPS sensor fixed my issue. Had it up to temp and put a lot of driving on it... most thus far. cold motor Key on TPS voltage = .51v, 0% TPS. hot idle 176-180*F TPS = .51-.53v and 0-.4 TPS %. IT never changed it was always 0% to .4% and my idle stayed rock solid at 600.
The only change I made besides the new TPS is I cleaned the IAC and TB a lot. I also removed the FMIC which caused much higher engine temps like 190-200*F which might have aggravated the TPS% issue. With the FMIC gone I run 174-180*F all day.
maybe u got a bad one? Have you checked the TPS plug? maybe see if it has enough slack? maybe you need to lower engine temps lol.
06-17-2016, 09:07 PM
#16
TECH Apprentice
Thread Starter
iTrader: (5)
Join Date: Jul 2010
Location: Pasadena, Maryland
Posts: 320
Likes: 0
Received 0 Likes
on
0 Posts
Nice, Carlisle is a nice show... I sometimes go in august for the vette show with my dad and brother. Never get up their for GM shows lol.
Well it seems the new TPS sensor fixed my issue. Had it up to temp and put a lot of driving on it... most thus far. cold motor Key on TPS voltage = .51v, 0% TPS. hot idle 176-180*F TPS = .51-.53v and 0-.4 TPS %. IT never changed it was always 0% to .4% and my idle stayed rock solid at 600.
The only change I made besides the new TPS is I cleaned the IAC and TB a lot. I also removed the FMIC which caused much higher engine temps like 190-200*F which might have aggravated the TPS% issue. With the FMIC gone I run 174-180*F all day.
maybe u got a bad one? Have you checked the TPS plug? maybe see if it has enough slack? maybe you need to lower engine temps lol.
Well it seems the new TPS sensor fixed my issue. Had it up to temp and put a lot of driving on it... most thus far. cold motor Key on TPS voltage = .51v, 0% TPS. hot idle 176-180*F TPS = .51-.53v and 0-.4 TPS %. IT never changed it was always 0% to .4% and my idle stayed rock solid at 600.
The only change I made besides the new TPS is I cleaned the IAC and TB a lot. I also removed the FMIC which caused much higher engine temps like 190-200*F which might have aggravated the TPS% issue. With the FMIC gone I run 174-180*F all day.
maybe u got a bad one? Have you checked the TPS plug? maybe see if it has enough slack? maybe you need to lower engine temps lol.
06-17-2016, 09:41 PM
#17
You should check it out! Glad yours is fixed, I'll try that tomorrow morning before I leave for the show. My car runs low 170s on a decent day and never goes over 190 in stop and go traffic. I don't think heat is the issue since it does it when the car is cold started too.
Hope u figure it out, maybe u can return the new TPS and swap it out. I've heard the PCMs get warm and do weird things depending on where yours is mounted. Engine temps are good.