I had a bad TPS so I replaced it with a working one. Now my idle goes back and forth between 1000 and 1500 RPM.

I tried rotating the TPS in different directions but it had no effect, besides when I turned it full clockwise (if looking at it from the drivers seat), the ECU would cancel it out as a bad TPS and throw a check engine light. Tried resetting the ECU (even though I knew that would accomplish nothing) and checked the tightness of the throttle cable. The irratic idle was irritating so I just unplugged the sensor all together in order to drive home. It idles at just under 2000 but at least it's smooth.

Any ideas? I'm all out!

 

vacum leak??? i dunno im just taking a stab in the dark

 

You can't just "slap on the TPS" and expect it to work.. it needs to be adjusted properly.. thats why OEM TPS sensors don't have removable screws.

Using a voltmeter, probe the signal and ground wire on the TPS. WHen the throttle is closed completely, it should read around 0.45v and at WOT it should read around 4.5v

Rotate the TPS accordingly until you get those results then tighten it down.

 

My idle did that with my cams until I turned my idle down. Try that...

 

I am having the same problem. My TPS voltage was out of spec, took the sensor off, replaced the screws with bolts for easier adjustability.

Could get the closed throttle to .45V but at WOT it only reads 4.1V. Still having major idle problems. Idles at 1500 after warm and sometimes surges.

Replaced IACV, FITV, throttle body gasket, cleaned throttle body, bled coolant, checkd for vacuum leaks and replaced idle adjustment screw. About the only thing left is a bad TPS.

Since the TPS is out of spec (only 4.1V at WOT) I am assuming it is bad. Checked the 3P connector with the switch on and 5V is getting to the TPS. Going to try a different TPS today.

You may try a different TPS- not sold seperately, have to get one off of a different throttle body. Make sure the actuator arm is inbetween the two tabs on the throttle.


[Modified by delSolLS, 3:47 PM 3/2/2002]

 

Hmm, thanks for the info guys. I'm gonna go grab a volt meter and try to "tune" the voltages like Crescent said.

delSolLS, let me know what you find out. I'm also doing this to my sol but I like to post model unspecific tech questions in here cause I used to have an Integra and I know there are some knowledgable people here.

Thanks guys.

 

Damn it this is so irritating. I rotated the TPS enough that it would read .45v at idle, but just like delsolLS, it only reads 41v at WOT. When I crank it up, it seems like it idles fine for a couple seconds, then it throws the TPS code as usual and the idle jumps up to 1800RPM. Any other ideas? Crescent?

 

Ok.. first.. make sure you didn't plug the MAP sensor plug into the TPS and vice versa... they are the EXACT same plug and can be easily mixed up.

As for your 4.1v at WOT - try setting the WOT to 4.5v first, then with the throttle closed see what it reads.. if its above 0.45v then slightly adjust the throttle stop screw that is behind/underneat the throttle linkage so that the throttle plate can close a little tighter.

 

Ok i got it to read approx .454 at idle and 4.60 at WOT. It starts up fine, no CEL, idles fine (but higher than normal) and runs like this for a while. Then it starts the irratic idle once again. Seems to happen when it warms up. The voltmeter goes from a steady .45ish to an insanely random display of numbers. Again my mind is boggled...

 

Hmm can you describe in more detail what happens?

So you start the car up and its cold? Everything runs fine (for how long)? You just let it idle for X amount of time and the suddenly it'll start to idle funny? Does it throw a TPS code at that time?

 

One more thing.. when you replaced the TPS sensor, did you make sure that you lined up the sprocket in the TPS with the notch in the throttle body? If its misaligned or not seated correctly, it will idle weird.

 

I am still having similar problems. I have tried everything and I can't get it to idle below 1500rpms. When decelerating, it also seems to take a while for the rpms to come down.

I have replaced the IACV, TPS, MAP, FITV and idle air adjust screw. TPS is from a DX so I had to swap outside wires. TPS is within spec .5V at idle 4.3 at WOT per Helms.

Checked for vacuum leaks, bled coolant, made sure TPS armature is in the grooves of the throttle.

WTF? I am out of ideas!

 

You got it. It doesn't idle "fine" per say but it idles smooth. The idle is high however, between 1500 and 1800 RPM. It will idle like this for a while but when it warms up, the stuipd bouncing idle returns. Still no CEL even when the idle is bouncing. Another strange thing is the TPS voltage when it is bouncing. Sometimes the voltmeter shows crazy irratic numbers, other times it shows a constant .454v yet the idle is still whack!

Yes I made sure i put the TPS in correctly. It wont even fit in the socket snugly if the tab isn't where it should be. Frustrated!

 

Ok.. screw in the idle adjustment screw all the way in. What is your fuel pressure set at? What injectors are you using and what fuel pump? What ECU?

 

Idle adjust screw all the way in. Fuel pressure 40-42 lbs. I still think this has something to do with the TPS. It has proper voltage swing, but I don't know what else could be wrong. All new sensors, no detctable vacuum leak, coolant bled.

This really sucks, what else could be wrong? Bad ECU?


[Modified by delSolLS, 5:22 PM 3/3/2002]


[Modified by delSolLS, 5:24 PM 3/3/2002]

 

My fuel pump, injectors, and ECU are all stock. I screwed the idle adjustment screw in all the way and it helped a lot! Now it usually idles at around 1100 RPM constant, but occasionally it will fluctuate back and forth around 100 RPM. I'm gonna try tinkering with it a bit more but this is much more "doable." It I can't get it idle any lower, I won't have much of a problem. THANKS AGAIN C!

 

I was having the same problem just last week. The idle would go up and down after warmed up.

1. I replaced all vacuum hoses and that didnt help.
2. Removed IAC valve and cleaned it out and now it idles rock steady, try checking that.

 

OK-

Idle problem finally solved! Probably a combination of things, but the final piece of the puzzle was the throttle stop screw.

Sometime, either before or during my problems, the bracket holding the idle stop screw got slightly bent. Repositioned it, readjusted the TPS and it idle like butter!

Well, lumpy butter do to the cams, but so much better than ever before!

The idle adjust screw acutally works!

Thanks to all who helped me look for solutions to this nagging problem.

H-T board is alway a wealth of info!

 

Glad to hear you fixed it...

but didn't i tell you to check the idle stop screw like a week ago??

 

Where is the idle stop screw? And where's the IACV? I'm having a similar problem with my car, except the idle doesn't get all funny when it gets warmed up. Instead, I just have a high idle when I come to a stop, and it takes a while for it to drop back down afterwards.

Thanks.

Oh yeah, and where's the idle stop screw?

I'll check on all of these after work.


[Modified by CKim, 11:40 AM 3/13/2002]

 

Idle stop screw is under the throttle spring on the tb. The IACV is normally on the back of the intake mani, but I don't know where they put it on the JRSC setup. Check the tension of the tb cable first, might be too tight, not allowing the throttle to close.





[Modified by Sleeper, 7:25 PM 3/13/2002]