code 121

[grngt50]

hey guys,

I pulled this code.... "121 O,C,R Throttle Position sensor out of self-test range" today and was wondering if anyone else has pulled this in the past and what you did to fix it. My car has a pretty high idle at startup (1100 rpm). There are no vacuum leaks and I have a BBK 70mm TB with the idle screw barley touching the throttle arm. Also, I know that the tps is not adjustable on our cars, but is that only on a stock TB?


James
94 GT VERT AODE
Ported stock intake, 4.10's, shift kit, Granatelli MAF, BBK 70mm TB, 14*, BBK adj fpr, 2 chamber flows, BBK O/R H pipe, BBK underdrive pulleys, MSD 6A, Walbro 190 pump, k&n with silencer removed, sub-frame connectors, fan switch mod, 160* tstat , weight reduction

 

[CManT1914]

TPS baselines on startup with the stock 94/95 computers. I'm not really sure what the code means, have you done a voltage test? At idle (engine running obviously) it should be around 0.50 to 1.0-volts, under WOT it should be between 4.0 and 5.0-volts. Key on engine off voltage should be right around 5.0 volts. Good luck

 

[grngt50]

I haven't tested the TPS because I don't have a voltometer. However, I did notice that the surface between the TPS and throttle body is bare (read: no gasket). Is there supposed to be a gasket there? How would that effect things if so?

 

[grngt50]

forgot to mention....

I also pulled a 332 code as well, which I believe is related to lack of EGR flow Can I eliminate or block the EGR (I dont have a Tweecer) and not have a problem with pinging? Does anyone have any pics on how they did theirs?

 

[R.J.]

did you just pull codes or did you scan for codes? If you used a scanner (EZ link, Snap-on ect.) sometime they require the throttle to be moved to WOT for a second to test the full range! I get this code when I forget to hit the gas and a "coolant temp sensor out of range" if the car is not warm during testing.

 

[grngt50]

I pulled the codes by using a jumper wire with flat blade quick disconnects........I then just counted the flashes of the check engine light. And I performed both two, one with the engine running and the other without.

 

[MysteryMachine]

for the egr one check the vac line going to the top of the egr valve. I think thats the on i pulled on mine messed with te vac line and it went away. As for the TPS do what the other guys say or replace it and see what happens. I upgraded Tb's and played with the idle and never had a code show up maybe its just bad

 

[grngt50]

anyone else have any thoughts on the 121 code? My chilton manual actually said that the throttle voltage at idle was higher than expected. Can someone please tell me what this means? Do I need a new tps? Could this be the reason for my high idle at startup?

 

[blackEagle]

anyone else have any thoughts on the 121 code? My chilton manual actually said that the throttle voltage at idle was higher than expected. Can someone please tell me what this means? Do I need a new tps? Could this be the reason for my high idle at startup?

This just happened to me. Only mine would idle at startup fine but, it would go to 2500 RPM when comming to a stop. It threw the 121 code and I had to get a new TPS to fix it.

 

[grngt50]

This just happened to me. Only mine would idle at startup fine but, it would go to 2500 RPM when comming to a stop. It threw the 121 code and I had to get a new TPS to fix it.

Yeah, I figured I'd end up having to spring for a new tps :damnit: By the way, what brand tps did you end up going with?

 

[blackEagle]

Yeah, I figured I'd end up having to spring for a new tps :damnit: By the way, what brand tps did you end up going with?

I got one from the parts dept at a dealer. None of the local stores had 1 in stock.