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p0121...searched

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Old Jan 7, 2008 | 07:33 AM
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Default p0121...searched

was on the highway the other day...running on cruise control at 75-80mph consistently.

after 2-3 hours of driving SES pops on

drove 100miles on the highway and it seemed fine. drove it around town a few times and it was fine. then the light turned off.

did the same drive home from vacation and the light came on again under similar conditions....cruise control at consistent speed for 2 hours...

scanned it finally and came up p0121.

did some searching and this doesn't seem to be an odd problem particularly with a cam, although more common with autos.
mines a manual....

and i've drove for 3yrs with the cam and never had the code come up. i've done the same type of highway driving with no issues.

could this actually BE a bad TPS?
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Old Jan 7, 2008 | 09:08 AM
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You should read this first http://www.hptuners.com/forum/showthread.php?p=101510
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Old Jan 7, 2008 | 10:01 AM
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been there, done that....thanks

the search turned up that page.

i don't have tuning software, i don't have any knowledge of tuning language. most of that was mumbo-jumbo.

and i also got the impression that was refering to Auto trans cars...with cams. mine is not auto.


since i've run the car for 3+ years with this cam...on the same tune...and have done many road trips with exact same conditions as this past one, but this time the SES came on.

is it possible that the TPS is actually the culprit?
i know guys love to throw the TPS in new when they see this code...according to various threads...but usually its a tuning issue.

but again, if it was tuning with mine....why would it take 3 yrs and 20 road trips to finally reveal itself?
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Old Jan 7, 2008 | 10:40 AM
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Impossible to tell without a scan at the bare minimum.

ANY car auto, manual or otherwise can get the p0121 code, its not auto specific, its a code, it doesn't care what kind of transmission you chose
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Old Jan 7, 2008 | 10:43 AM
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what would i need to look for on a scan?

i've got scanning software to look at real time engine data.

i'm just not sure anything would show up since this doesn't seem to be a problem with around-town driving.
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Old Jan 7, 2008 | 10:45 AM
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you'd want to look for the thresholds in that DTC link, but without your tuning file it makes it even more difficult because its possible your tuner tweaked those min/max limits as well(I probably would've with your cam).
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Old Jan 7, 2008 | 12:23 PM
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i can't figure out why a problem with the tune would take 3yrs to show up?
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Old Jan 7, 2008 | 12:35 PM
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neither can I but I'm just trying to help
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