tuning problem.

[sleepyalero]

okay so i got a HPT pro. was toying around with it today running some diags... and came across something interesting..

when i hook the tuner up to the car, with it in the ON position, i press the pedal down, tps % reads 50%. now lets back up here.... if i EASE into the pedal to the floor it will read 50%, if i smash the pedal down quick, it says 0.

i went driving to test it, sometimes it wouldnt read when floored, if i eased into in in say second gear... after doing a few pulls, the max i could get the tps % was 84.

im confused what the problem is here... i looked at the dtc codes through the tuner, sure enough two came up for the tps. P0122 and P0111 or P0121, something like that, low voltage (premmature) and some other things, i forget, but thats the jist of it...

put the tuner in fisdads alero, tested his tps. weather i punch the gas fast, or ease into it, it goes up to 100%.

i dont know whats wrong here.... dont know where to look... or how to fix this atm... im curious on if this is causing my high idle issues at recent start ups after WOT.

i plan to pop the hood in a second and check the connections, the tps is literally a month old. i did the TPS relearn with no luck...... any help would be great.

[sleepyalero]

well, just looked, all wiring and connections to it look fine.

the sensors are from autozone, could it just be there sensors are just junk? thinking about going to napa, replacing the tps with one of theres, and see if it works?

[stewartfn18]

sounds like the tps isnt sending the right signals to the pcm. id recommend replacement with an acdelco one

[sleepyalero]

Hmmm. Thats an idea. But where could i get one other then dealer? Or by ordering?

[MAC the KNIFE]

my obd2 scanner shows the same number i think at wot. 84% at WOT instead of 100. (on the g8)

[AaronGTR]

Originally Posted by sleepyalero

Hmmm. Thats an idea. But where could i get one other then dealer? Or by ordering?

Could check on rock auto. They usually carry a bunch of brands including AC delco and Delphi. I was gonna suggest the TPS relearn procedure, but you said you already did that so... it's got to be either an issue with the wiring, or the sensor itself. If the throttle plate is opening all the way, it should read close to 100%, and if you've done the relearn procedure it should know what the lower and upper voltage limits are and scale appropriately.

Originally Posted by MAC the KNIFE

my obd2 scanner shows the same number i think at wot. 84% at WOT instead of 100. (on the g8)

have you tried doing the TPS relearn procedure Mac?

[MAC the KNIFE]

Originally Posted by AaronGTR

have you tried doing the TPS relearn procedure Mac?

nah. it's fast enough with only 84% throttle

[stewartfn18]

id say rockauto is going to be the cheapest and easiest to get a acdelco one. mac you also have dbw. those never see true 0 percent and 100 percent

[sleepyalero]

well whats weird is fisdads car showed 100% no problem, i plan on probably going to car quest today and getting a AC DELCO TPS from car quest to see what happens there.

im pretty sure the throttle plate does open all the way.

[sleepyalero]

well i just got a new TPS from car quest. 44$ + tax. installed and plugged the tuner in. did a TPS relearn before i actually ran a scan. car now goes up to 100% TPS. but it still shows im throwing DTC's.

before changing sensor i got.... i believe same as last night.. as follows what it says in HPT.

[] P0122 - Throttle position (TP) sensor circuit low voltage (immature)

[] P1122 - throttle position (TP) sensor circuit intermittent low voltage (history) (immature)


and now im getting as of 5 mins ago... (after TPS was replaced)

[] P1122 throttle position (TP) sensor circuit intermittent low voltage (pending) (history) (immature)

[HenryM]

You may have a bad connector, Napa sells the pigtail, get one splice it on, do the relearn procedure again. Usually what happens is the wire inside the insulation begins to break, so gradual that you won't notice till something like this happens. Seen this prob across the board will all makes and models in the shop.

[sleepyalero]

Thats a possibility... But it seems a little unlikely for the pigtail to be bad?

[HenryM]

Happens more often than you would think.

[HenryM]

Napa sells them quite often to the local techs here, part number is EC89, you can see if that part number crosses over to another brand the your FLAPS carries. But Echlin has a stellar rep.

[sleepyalero]

alright cool, thanks for that. ill probably look into it if nothing else solves it.

im about to do another scan.. see if the code cleared after a little bit of driving.


but where the eff is aaron!!! usually hes the guru on the site.... SHOW YOUR SELF.

[sleepyalero]

just did another scan, cleared codes from last initial scan, the tps code has not come back as of the most recent scan (3 mins ago) and i checked the iac position at idle, it sat at 13, and would sometimes go up to 14, but would hold a pretty steady 13. the tps still goes to 100% as well so thats good there...

[stewartfn18]

sounds like your problem is solved

[sleepyalero]

Nope. Codes are back....

Right as i floored it the same 2 codes above came back

[geldartb]

i'd say you got a wiring problem then.. stop spending money on sensors and diagnose the wiring.. nothing pisses me off more than electrical problems but tracking them down sure beats throwing money at sensors.

i've had my top end off the engine more times than you wash your car when i first put the engine together.(troubleshooting shit) and the wiring harness has been moved around more than i care to remember and i never had a problem..

i'd look into the wires going to the TPS..do you have a multimeter you could measure the plug end with..

the only thing i have a problem with is MAP sensors and given that they were all junkyard pulls i'm not really holding anything against the sensor .that was because i decided to go with the 3500 style sensor which is also found on J-body 4cly's.finally got an ac delco oem replacement.

[AaronGTR]

Originally Posted by sleepyalero

alright cool, thanks for that. ill probably look into it if nothing else solves it.

im about to do another scan.. see if the code cleared after a little bit of driving.


but where the eff is aaron!!! usually hes the guru on the site.... SHOW YOUR SELF.

Aaron is doing homework. Anyway I agree with Henry. If you've already replaced the sensor and the new one is reading good, but you are getting voltage codes, then it is more likely a loose connector or frayed wiring. They can get bad from the wire flexing over and over. Best to just replace it. only other possibility would be a bad PCM.