Accelerated warmup problem?
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Joined: Dec 2002
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From: Portland
Accelerated warmup problem?
Ok, so here's the deal. I start my car and it goes up to 2800-3000 for a few seconds like it always has, and then it drops down and holds at 1500 and holds like it always has (or when i start it in gear it just holds at 1500 like it should). The problem is that once the temp starts to come up, the idle raises slowly to 1900 instead of lowering like it used to. Even once the temp gauge reads what looks like full operating temp, the idle still sticks up there. After about 15 minutes of normal city driving, the idle will come down and sticks at 750 just like its supposed to, and the car drives exactly like it should. I'm thinking this is a problem with the warmup system because it is definately still in warmup mode while the idle is high (I can tell that the car isnt leaning out the mixture). I installed a new thermostat thinking that it must just be opening way to early but that didnt fix the problem. So here I am, help me out guys.
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From: Coldspring TX
Couple of things:
1) you could read the BAC's output at the ECU and see if it's the animal causing your problems (the voltage should rise towards about 13v as the car warms up and the BAC de-energizes)
2) you done anything to the car lately, especially something that might have caused a vac leak? Note that if you had a huge leak, the 3k warmup wouldn't kick in in the first place. Been there.
Checked the TPS lately?
The thermo-wax/fast idle system?
1) you could read the BAC's output at the ECU and see if it's the animal causing your problems (the voltage should rise towards about 13v as the car warms up and the BAC de-energizes)
2) you done anything to the car lately, especially something that might have caused a vac leak? Note that if you had a huge leak, the 3k warmup wouldn't kick in in the first place. Been there.
Checked the TPS lately?
The thermo-wax/fast idle system?
Thread Starter
Senior Member
Joined: Dec 2002
Posts: 392
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From: Portland
k, cleaned the BAC valve, that didnt fix it. I dont see why it would be the TPS since it runs/idles flawlessly after the 15-20min "warmup period", but I'm going to check it anyways today..... Does the coolant temp sensor have anything to do with idle? I know that the car runs a richer fuel mixture when cold, so if my car is staying in warmup mode do you think that the sensor could have gone bad? I dont really want to remove the thermowax, especially since I'm pretty sure it isnt causing my problem. Any further input would be helpful. Thanks
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Jeff20B
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Sep 16, 2018 07:16 PM