93 Throttle position sensor
Thread Starter
Drifting
Joined: Oct 2003
Posts: 1,349
Likes: 18
From: Dallas Texas
93 Throttle position sensor
Guys
have a 93 Ruby with 85K miles - sometimes at startup it will jump a bit like an idle surge...lately low idle has been a bit rough...is the throttle position sensor on its way out?
have a 93 Ruby with 85K miles - sometimes at startup it will jump a bit like an idle surge...lately low idle has been a bit rough...is the throttle position sensor on its way out?
Drifting
Joined: Jun 2010
Posts: 1,853
Likes: 8
From: Westerly RI
Not necesarily- Check for carbon buildup around the throttle plates and IAC pintle. Also, look for sticking throttle cable that doesn't always return fully. And, check for cracks, etc. in vacuum hoses just while you're at it. Does this happen on cold startup only, warm startup, or both?
Drifting
Joined: Jun 2010
Posts: 1,853
Likes: 8
From: Westerly RI
If your problem is intermittent, I would add to my previous suggestions, check wiring connections to CTS and check operation of EGR valve and its vac. hoses. It might be worthwhile to pull codes, can't hurt.
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Le Mans Master
Joined: Jan 2006
Posts: 5,621
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From: Orlando FL
Here is a couple of suggestions to get the easy possible causes out of the way
1- Clean the MAF wires and throttle body (carefully using only throttle body cleaner).
2- Clean the IAC plunger and seat.
I just read a post about having a similar problem. He could not get the IAC seat and surrounding area clean while it was on the car. It had to be removed to be cleaned properly and it did fix the problem in that case.
You can always measure the wiper (might be DK Blue wire) of the TPS with a volt meter with the key on, engine does not have to run. Move throttle to open position while monitoring voltmeter. Voltage should go from about 0.4 volts to 5.0 vdc. Look for smooth transition. This would eliminate the TPS without having to remove or replace it.
1- Clean the MAF wires and throttle body (carefully using only throttle body cleaner).
2- Clean the IAC plunger and seat.
I just read a post about having a similar problem. He could not get the IAC seat and surrounding area clean while it was on the car. It had to be removed to be cleaned properly and it did fix the problem in that case.
You can always measure the wiper (might be DK Blue wire) of the TPS with a volt meter with the key on, engine does not have to run. Move throttle to open position while monitoring voltmeter. Voltage should go from about 0.4 volts to 5.0 vdc. Look for smooth transition. This would eliminate the TPS without having to remove or replace it.
Thread Starter
Drifting
Joined: Oct 2003
Posts: 1,349
Likes: 18
From: Dallas Texas
well
cleaned up the IAC - not really that bad - and same condition...
starts off about about 750 650 idle and then drops off to about 500 and the rumble rough - so I guess its either a TPS or an opti weekend!
cleaned up the IAC - not really that bad - and same condition...
starts off about about 750 650 idle and then drops off to about 500 and the rumble rough - so I guess its either a TPS or an opti weekend!
