1982 c3 high idle
Racer
Joined: Nov 2018
Posts: 295
Likes: 104
From: Toronto Canada
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
OK, like I posted back in post #2 and #4. Check your TPS sensor. The sensor can be bad and NOT set a CEL, it happens sometimes. If it is NOT reading correctly, it IS bad. If it has a dead spot, it IS bad. Set the new one to .525v and it will be fine. The GM service manual is pretty good if you know how to use it and actually follow it. You WILL usually find the issue and come up with a solution/fix. This is the same thing with the IACs. They can test OK ohm wise and still be bad and pintle does not move and WILL not always set a CEL.
The GM manual DOES explain how this works... The TPS is what tells the ECM where the throttle blades are in relation to idle. If the voltage is too low and too high from .525v, that changes what the ECM thinks is the real idle position of the throttles blades. I think you really need to sit down and read the GM manual in detail more than once to understand how CFI works. GL
The GM manual DOES explain how this works... The TPS is what tells the ECM where the throttle blades are in relation to idle. If the voltage is too low and too high from .525v, that changes what the ECM thinks is the real idle position of the throttles blades. I think you really need to sit down and read the GM manual in detail more than once to understand how CFI works. GL
Thread Starter
Racer
Joined: Oct 2021
Posts: 436
Likes: 15
From: Maryland
I did follow the service manual, did all the checks for the TPS and did some tests of my own, determined it is bad. I bought a replacement one. I am also about to test for air leaks on the tb gasket using a smoke machine.
Racer
Joined: Nov 2018
Posts: 295
Likes: 104
From: Toronto Canada
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Well again, like I already told you back in post #2 and #4 about your TPS sensor and you wanted to know why I thought the TPS was suspect as if you were doubting me. I have 30 years of experience specifically with 82/84 corvette not to mention the camaro, firebird and trans am crossfire injection cars. You can listen to these other people on the crazy ideas they have on what is wrong if you like and go down the rabbit hole on a parts swapping challenge. or, you can listen to what I tell you and follow the GM manual to the "T" to fix your car. The choice is yours and good luck on your fix...OUT!
Racer
Joined: Nov 2018
Posts: 295
Likes: 104
From: Toronto Canada
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Racer
Joined: Oct 2021
Posts: 436
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From: Maryland
Well, I apologize. I wasn't doubting you, nor do I doubt anyone on this forum. The reason I ask so many questions is because I want to learn what your thought process is, so I can learn from it and replicate it again should another problem arise. Theres gonna be a point in the future where my grandfather isn't around and this forum doesn't exist anymore, so if I want to keep this car for another 60 years I need to learn as much as possible now. If my questions get annoying please let me know.
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Racer
Joined: Oct 2021
Posts: 436
Likes: 15
From: Maryland
) but I do have the snap on scanner that gives me the readings. I was just wondering if that could give me a hint.
Thread Starter
Racer
Joined: Oct 2021
Posts: 436
Likes: 15
From: Maryland
Thread Starter
Racer
Joined: Oct 2021
Posts: 436
Likes: 15
From: Maryland
Melting Slicks
Joined: May 2021
Posts: 2,265
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From: Fleming Island, FL
I'm going to respond to this. No, I don't have 30 years experience with the Crossfire. I have 42 year's experience in the automotive field. My ideas are not crazy and the only part I suggest to replace was a $5 thermostat when the OP said the coolant temperature was only getting to 130 after 15 minutes after you suggested to check TPS and that 900 RPM isn't all that high. I've been following the OP's other threads and it's obvious he's got some serious electrical problems with this car. I've got a ton of electrical experience on Mack trucks. They got computers tied together on a CAN network, a 4 inch diameter wiring harness with 70 relays in the dash, and a service manual with a 130+ pages of wiring diagrams. Not to mention a body that get mounted on these chassis and with systems that are integrated with the chassis wiring, all bouncing around for hundreds of thousands miles. I've seen those quote "crazy ideas" unquote hundreds of times. I don't claim to be a Crossfire expert. However I believe that I've have some valid points.
Thread Starter
Racer
Joined: Oct 2021
Posts: 436
Likes: 15
From: Maryland
TPS replacement complete, Im getting a non 0 reading now! I have to wait till I warm up the engine to calibrate it to .525, until then doing a parking brake replacement. Once those 2 things are done, if idle is still high time to check for air leaks in TB
Thread Starter
Racer
Joined: Oct 2021
Posts: 436
Likes: 15
From: Maryland
oh I thought engine warm was a requirement. Will do. Just found out the “delivery date” on an autozone part means the day they will ship, not the day it arrives. So my parking brake is arriving in 5 days instead of today. My first and last time buying online from them…
Thread Starter
Racer
Joined: Oct 2021
Posts: 436
Likes: 15
From: Maryland
Right so just ran engine. Idle at 1000 after 10mins. I connected my scanner after the 10 min run and it only shows rpm and 02, no other PIDs. I pulled the negative out of the battery earlier for a few minutes, so the ECM might have reset. Do I need to drive it for a few miles?