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Old 10-13-2004, 04:35 PM   #1
OneOBS
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Default TPS Adjustment

Anyone got a link to the procedure?
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Old 10-13-2004, 04:46 PM   #2
kiltjim
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Didn't you get the memo?

I'm sorry I couldn't resist. And unfortunately, I have no idea what you're talking about.
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Old 10-13-2004, 05:39 PM   #3
jamesfacts
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PM MYfirst00... I think he's got it.
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Old 10-13-2004, 05:41 PM   #4
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I thought this was dubbed a bad idea?
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Old 10-13-2004, 08:53 PM   #5
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I think that it is a good idea to adjust it once in a while. I drove my car for 2 years running with a TPS that only had 4.1 out of 5.1 volts. I had a hell of a time trying to get something to activate at WOT when it only put out 4.1 volts. It's funny how many people I beat on 4/5 throttle.
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Old 10-13-2004, 09:15 PM   #6
OneOBS
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Quote:
Originally Posted by americanyouth
PM MYfirst00... I think he's got it.
LOL!

Quote:
Wow, who gave you that info? The only TPS I've ever adjusted was on a 1994 SVX and that was when I messed it up by doing so. I don't have any directions man, sorry!
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Old 10-14-2004, 12:17 AM   #7
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Quote:
Originally Posted by OneOBS
LOL!
Eh... I knew had needed to do it at one point!
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Old 10-14-2004, 08:28 AM   #8
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So, somebody explain this one already!
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Old 10-14-2004, 09:42 AM   #9
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Unless you have the 4-pin TPS, you don't need to adjust anything.

The TPS is simply a potentiometer that is hooked up to the throttle plate. As the throttle is opened, resistance is changed. That information is sent back to the ECU to know what position the throttle is in.

The reason I say it's not necessary to adjust the TPS is that the ECU will take a reading of the TPS's resistance at startup. It then uses that as it's "throttle closed" benchmark. If you adjust the TPS while the car is running, you can make the idle go up and down. If you leave the TPS adjusted so the idle is high, turn off the car and turn the car back on, the idle will return to normal.

However if you adjust the TPS too far, its readings will be outside the set limits in the ECU, and the ECU will throw a CEL.

On the 4-pin TPS's they had the idle switch in the TPS as well. The newer cars have a separate idle switch. So on the 4-pin TPS's you would adjust the TPS based on the idle switch to make sure it's readings are correct.

here's the test procedure. Last scan tells you how to adjust the TPS via the idle switch

http://www.main.experiencetherave.co...S_testing1.jpg
http://www.main.experiencetherave.co...S_testing2.jpg
http://www.main.experiencetherave.co...S_testing3.jpg
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Old 10-14-2004, 10:43 AM   #10
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Wow, cool! Thanks!
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Old 10-14-2004, 11:12 AM   #11
OneOBS
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Cool, thanks. Its exactly what I needed. Its not the TPS I need to adjust. Its the idle switch.
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Old 10-14-2004, 11:56 AM   #12
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Here's the diag pages for the tps from the 02 fsm.

It's not really super helpful IMO. For the idle switch circuit you want to use the first two scans I believe.

http://www.main.experiencetherave.co...PS_testing.pdf

Why do you want to adjust this? Are you having any problems?
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Old 10-14-2004, 12:32 PM   #13
OneOBS
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Surging off idle. Its not a problem in normal driving, however if I am backing out of the driveway (in gear at idle RPM or a tad more), the car surges real bad.
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Old 10-14-2004, 02:46 PM   #14
Legacy777
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Hmm.....does it happen only when cold, or when the car is warmed up?

You have the 2.5 liter motor correct? What octane fuel you using?
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Old 11-03-2004, 08:18 PM   #15
OneOBS
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I tried the procedure posted above last weekend and it doesn't work. Pins one and two are not the idle switch (nor do any other combinations of the other pins prove to provide continuity when the throttle is closed).

I do, however, seem to have fixed my surging off idle problem with a new air filter. The car only has 6500 miles on it. Go figure.
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Old 11-03-2004, 09:48 PM   #16
Legacy777
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hmm....maybe the sensor is different for non-turbo and turbo engines?
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Old 11-04-2004, 02:12 AM   #17
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adjusting the TPS on a 2.5 motor is blatenly a BAD idea, trust me, tried it, the car flips out with even .05 extra volts at idle. Leave it alone it's preset at the factory
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Old 04-08-2005, 08:54 AM   #18
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Default TPSs [B]do[/B] require adjustment.

Quote:
Originally Posted by Legacy777
The reason I say it's not necessary to adjust the TPS is that the ECU will take a reading of the TPS's resistance at startup. It then uses that as it's "throttle closed" benchmark.
NOT... Bad logic, plain and simple.

Consider the blockhead that depresses his throttle 1/3 of the way down before he turns his ignition on.

Are you going to try to convince me that 1/3 throttle is now assumed to be the 'throttle closed benchmark' for the ECU. I should say not.

Read the service manual. The ECU uses the voltage in the TPS feedback loop to interpret throttle position, simple as that. 1.2v and under, the ECU assumes idle. As the voltage in the feedback loop approaches 5v, the ECU then sees WOT. Simple as that.
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Old 04-08-2005, 09:10 PM   #19
Legacy777
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Quote:
Originally Posted by figgskzoo
NOT... Bad logic, plain and simple.

Consider the blockhead that depresses his throttle 1/3 of the way down before he turns his ignition on.

Are you going to try to convince me that 1/3 throttle is now assumed to be the 'throttle closed benchmark' for the ECU. I should say not.

Read the service manual. The ECU uses the voltage in the TPS feedback loop to interpret throttle position, simple as that. 1.2v and under, the ECU assumes idle. As the voltage in the feedback loop approaches 5v, the ECU then sees WOT. Simple as that.
So you dug this thread up to tell me I'm wrong. Hmm....I said nothing about the blockhead who holds the throttle down. Yeah if he holds it down and then releases it, the ECU will know what's going on and adjust.

What I'm specifically talking about is moving the position of the TPS by loosening the screws that hold it to the TB. I'm talking moving it several centimeters at most. There's no need to do this, due to how the 3-pin TPS is setup.

I've done what I've said on the car....so I know what I say is not BS....so say whatever you want....I really don't care.
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Old 11-02-2005, 05:22 PM   #20
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im diging this thread up for the pics that no longer exist.
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Old 11-02-2005, 08:21 PM   #21
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Seen it.
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Old 11-02-2005, 08:21 PM   #22
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who...i just posted before you did.....wt-h?
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Old 11-02-2005, 09:20 PM   #23
Legacy777
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replied to your thread on the USMB.
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Old 11-02-2005, 09:40 PM   #24
Legacy777
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wow....something got screwed up with the server's time stamp....maybe something to do with DST.
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Old 11-02-2005, 11:24 PM   #25
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very interesting.
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