94CamaroZ28SS

I am having problems with my LT1 in sig. the idle jumps up and down and sometimes i shifts really hard or holds the gear for way too long. I have replaced the TPS sensor months ago and it went away but now its back and im clueless??? i can also smell fuel really well when i am sitting idle. I have attached the file if someone can look at it and point me in the right direction??

http://www.mediafire.com/?sharekey=0...4e75f6e8ebb871

94CamaroZ28SS

No one wants to help out a LT1 Owner???

Mike454SS

iTrader: (4)

I couldn't look at the file at work, I will download it now and see if I can help.

Jditlfm

iTrader: (26)

there is nothing wrong in that log rpm went up consistent with your tps signal

Mike454SS

iTrader: (4)

I think your TPS is still screwed up. I never see it go to 0% when you're at idle, and I see low voltage at what I think is full throttle...look between records 504 and 552...I think you were holding the throttle on the floor there, but your TPS fluctuated a good deal through the 60-70mph range (2nd gear I think). That will also screw up how it shifts.

At record 555 I think you were completely off the throttle, but it showed 2.4% and high voltage for being closed all the way until record 752 where it looks like you got back into it.

Seems to me like a bad TPS, or a TB that is damaging your TPS...which TB do you have?

Mike454SS

iTrader: (4)

Take another look man, his TPS isn't reading properly at all.

Jditlfm

iTrader: (26)

Good call I completely overlooked that. I would say either the throttle stop screw is not adjusted properly (stock throttle body) and or the holes on the sensor need to be slotted and adjusted (aftermarket throttle body)

Mike454SS

iTrader: (4)

I'm still disagreeing with you, the voltage is too high at idle and too low at WOT...and fluctuates at both...that says the sensor is damaged, it might be damaged due to the TB...but adjusting the TB isn't going to fix the current sensor.

94CamaroZ28SS

I have the stock TB.

94CamaroZ28SS

ok well i replaced the TPS Sensor and i took another recording here is what i got.

this is with the motor off and just me hitting full throttle!
http://www.mediafire.com/?sharekey=0...eada0a1ae8665a

this one is with the motor running!
http://www.mediafire.com/?sharekey=0...eada0a1ae8665a

car seems to run fine now but i havent driven it too much! Is the rest of the readings look good? do you notice any other problems?

WhitePhoenix99

iTrader: (12)

I'm having similiar problems, however my car has died a few times after coming to a stop. Would a bad tps sensor cause the car to die?

Mike454SS

iTrader: (4)

I don't think a bad one would cause it to die...but I guess anything is possible.

Mike454SS

iTrader: (4)

It seems fine at idle now...if you want to get a log driving it around including some full throttle I'll take a look at it for you.

94CamaroZ28SS

Ok i will do that today

Jditlfm

iTrader: (26)

I disagree the high voltage at idle could be the stop screw and not getting full 100% tps could be a linkage/ throttle body shaft and or air intake hose clamp stopping it from going 100%. Either way a good or bad tps sensor is not going to make the rpms jump. It could cause a hesitation if it has a dead spot in it but not usualy a jump in rpms. Plus he said it was already a new one. so two bad tps sensors in a row is a stretch.

94CamaroZ28SS

is there a certain way to adjust the stop screw?

When the TPS went out last APRIL it would IDLE at 1500 RPMS!! so when the TPS goes out on my car it tends to raise the Idle.

Now if i could find out why the TPS are going out???

Since i have replaced the TPS the idle is fine and the car seems to have more power and shift when its supposed to!

Mike454SS

iTrader: (4)

The combination of a TPS and a shitty tune (mail order tunes usually are) WILL make the car idle funny due to the closed TPS spark advance table not lining up properly with the main spark advance table for similar vacuum numbers as well as all the idle stuff in the PCM not really being able to work, like the over/under spark tables and the IAC tables. Also if you look more carefully at his original log before jumping to conclusions you will see that the voltage fluctuates while he's slowing down/stopped...which tends to say his foot isn't hitting the gas pedal...which tends to say the sensor is bad...it's also fluctuating in voltage at full throttle...I don't know about your right foot...but mine pins the TB on the stop and keeps it there until I decide I'm done being at full throttle...and that has always, in every car I've logged while driving, resulted in 1 voltage number for the entire WOT trip.

And a new TPS sensor seems to have "cured" the car again...something either caused them both to go bad, or he's buying cheap parts store brand sensors...I've seen people kill them with a pressure washer on the engine before, and I've seen aftermarket TB's (usually Holley's LT1 TB's are the worst) damage the sensors too.