TPS reads 2.4% when throttle is closed. WTF?
TECH Enthusiast
Joined: Mar 2004
Posts: 647
Likes: 0
From: Australia
Reset the TPS when warm, ie., when the car starts reporting the problem.
Engine off
Pull out TPS connector
Turn on ignition
Wait till SES light
Turn ignition off
Plug back in TPS connector
Start her up!
If that fails, then im at a loss. Perhaps a new TPS sensor is the go...
Engine off
Pull out TPS connector
Turn on ignition
Wait till SES light
Turn ignition off
Plug back in TPS connector
Start her up!
If that fails, then im at a loss. Perhaps a new TPS sensor is the go...
Originally Posted by MNR-0
Reset the TPS when warm, ie., when the car starts reporting the problem.
Engine off
Pull out TPS connector
Turn on ignition
Wait till SES light
Turn ignition off
Plug back in TPS connector
Start her up!
If that fails, then im at a loss. Perhaps a new TPS sensor is the go...
Engine off
Pull out TPS connector
Turn on ignition
Wait till SES light
Turn ignition off
Plug back in TPS connector
Start her up!
If that fails, then im at a loss. Perhaps a new TPS sensor is the go...
any new info on this pat my car is doing the same thing my tps stays at
2%off the throttle tried resetting it goes to 0 untill i blip the throttle a few times then sets itself back to 2%
2%off the throttle tried resetting it goes to 0 untill i blip the throttle a few times then sets itself back to 2%
On The Tree
Joined: Feb 2006
Posts: 156
Likes: 0
an easier fix would be to change the Min "TPS throttle position % to disable the main timing tables" from the factory setting of 1.2% to 3 %. That way anytime your ECM see 3% or less on the TPS sensor it will refer to the idle timing tables instead of hanging in the main spark table.
I had the same problem. After the motor was good an warm it would idle high ~1300-1500rpm. TPS readings were slightly above Zero. cable was fine as well as the throttle blade position, etc. It did this for weeks as I tried to tune it out. I replaced the IAC, no change. I removed the TPS. Visually it was OK. I moved it manually back and forth a few times through its range of motion. I plugged it back up, started the car and let it idle a little. I unplugged the TPS while it was running just to "shock the system" a little and make it try to relearn or something. The motor shut off immediately. I plugged it back and and the problem hasn't reoccurred. Hope this helps. 
Patrick did you find out what it was? I am having a similar problem. I had my car looked at tonight and my voltage was .56 with 0 % position and it would also be .56 with 3% position. Timing would be 34 at 3% and 22 at 0%.
TECH Enthusiast
Joined: May 2007
Posts: 538
Likes: 0
.49-.60 is normal TPs range. below .49 is assumed TPS value for TPS low voltage fialure. Check mode 6 data I bet you have a ppending Low TPs voltage code. Its most likely going into a failure state.
Originally Posted by Patrick G
If I had my scanner at higher resolution, I'm sure I'd see that one was something like 0.42V and the other was 0.43V. My TA has traction control, but the fuse has been pulled for over a year. This TPS problem just started happening a few weeks ago. Again, when the TPS reads 2.4%, the throttle is completely closed and the throttle cable has slack in it (so it's not the traction control cracking the blade or anything like that). 
I have an EFI Live/Moates Road Runner for a PCM. It's been in the car for about a year and it's never given me a problem.
I have an EFI Live/Moates Road Runner for a PCM. It's been in the car for about a year and it's never given me a problem.
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^^ I have that code, I think its p0121. It says low voltage for tps or app sensor what ever the app sensor is. I was driving today and my alternator voltage went to 13 volts and my gauges were doing something funny. I'm putting in a new tps sensor tomorrow. I wonder if this could be charging related in both of our cases.
On a side note,
TRENT GREEN IS A DOLPHIN and CULPEPPER IS GOING
On a side note,
TRENT GREEN IS A DOLPHIN and CULPEPPER IS GOING TECH Enthusiast
Joined: May 2007
Posts: 538
Likes: 0
for the 5v refernce line to dorp low enough to set a p0121 you would have to be below 9v at the charging side of things. Generally the car will shut itself off at that point.
Originally Posted by 98Camarod
^^ I have that code, I think its p0121. It says low voltage for tps or app sensor what ever the app sensor is. I was driving today and my alternator voltage went to 13 volts and my gauges were doing something funny. I'm putting in a new tps sensor tomorrow. I wonder if this could be charging related in both of our cases.
On a side note, TRENT GREEN IS A DOLPHIN and CULPEPPER IS GOING
On a side note,
TRENT GREEN IS A DOLPHIN and CULPEPPER IS GOING So in my case the tp sensor is probably going? It didn't drop below 13 volts. What is an app sensor?
To the op, have you cleaned the connections on the ecm yet or found the solution?
To the op, have you cleaned the connections on the ecm yet or found the solution?
TECH Enthusiast
Joined: May 2007
Posts: 538
Likes: 0
APP is essentially a load calculation. If the TPS and the MAP don't match up for a given RPM range you will get APP codes. If you have a 90mm TB the TPS vsRPM vs AIRFLOW table made need adjustment. Its the PCM's way of sanity checking the MAF and TPS rationality for a given airflow rate..
Originally Posted by 98Camarod
So in my case the tp sensor is probably going? It didn't drop below 13 volts. What is an app sensor?
To the op, have you cleaned the connections on the ecm yet or found the solution?
To the op, have you cleaned the connections on the ecm yet or found the solution?
Thread Starter
Joined: Nov 2001
Posts: 8,246
Likes: 34
From: Victoria, TX
This problem has not gone away. I am about to burn the car to the ground! 
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
I posted earlier about resetting my TPS but that only worked for a while. I still have this problem too. It seems like I am endlessly idle-tuning, and I've found that with some combinations, that "high idle" error I see when I put the car in park varies. With some combos it may be 1100, with others 1400ish. Turn on the AC and it jumps a little higher. In each of those cases its pretty consistent with that new high-idle set point it finds, so it looks like it should be possible to tune out. I still can't get my mind around what's happening, but I too am thinking that it is something electrical or in the program.
At this point I'm thinking its not related to any of the delay settings on idle. Now I want to think its some mismatched combo of idle air, timing, and VE. I don't think it depends so much on the desired idle speed because my problem started out of the blue when I was doing fine for some time with 950. Then I tried fixing that and I actually had it idleing more or less decently at 850 but with the same issue. The thing is I could tune it, and sometimes it would immediatley show the problem, but then other times it might be fine for a day or two and then fall back into this pattern after some learn-time. I changed the IAC, but after reading this thread I haven't changed the TPS yet.
Relevant mods in my case: FM13 cam, PP stage 2 heads, SVO redtops, LS6 manifold, stock maf, ported TB. Macs, ory w/ 3.5" collector transitioning to 4" mufflex. Still burning oil like a champ even with GC0W30 (You know I would think this combo should be fairly easy to tune.
)
At this point I'm thinking its not related to any of the delay settings on idle. Now I want to think its some mismatched combo of idle air, timing, and VE. I don't think it depends so much on the desired idle speed because my problem started out of the blue when I was doing fine for some time with 950. Then I tried fixing that and I actually had it idleing more or less decently at 850 but with the same issue. The thing is I could tune it, and sometimes it would immediatley show the problem, but then other times it might be fine for a day or two and then fall back into this pattern after some learn-time. I changed the IAC, but after reading this thread I haven't changed the TPS yet.
Relevant mods in my case: FM13 cam, PP stage 2 heads, SVO redtops, LS6 manifold, stock maf, ported TB. Macs, ory w/ 3.5" collector transitioning to 4" mufflex. Still burning oil like a champ even with GC0W30 (You know I would think this combo should be fairly easy to tune.
) Thread Starter
Joined: Nov 2001
Posts: 8,246
Likes: 34
From: Victoria, TX
Originally Posted by LS1curious
whats the TPS volatge at with the throttle closed.
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
With the TPS off the TB and fully crunk down, do you get
a lower reading than 0.6V (which I think is kind of marginal
as the PCM sees it)? If so try elongating the holes and
make it so you have a little bit of angle play for adjustment?
If it's 0.6 at the limit of sensor (not necessarily blade) travel
then I'd wonder about reference and ground values, offsets
and the like. Does the voltage you measure with a DMM and
two sewing needles, equal the voltage the PCM reports?
a lower reading than 0.6V (which I think is kind of marginal
as the PCM sees it)? If so try elongating the holes and
make it so you have a little bit of angle play for adjustment?
If it's 0.6 at the limit of sensor (not necessarily blade) travel
then I'd wonder about reference and ground values, offsets
and the like. Does the voltage you measure with a DMM and
two sewing needles, equal the voltage the PCM reports?