timbogates

I had a very intermittent problem the other day with my Crown Vic. This problem does not occur very often. It typically occurs in hot weather when I have used my air conditioner. The following codes have presented themselves: P0153, P0430

It did this the other dya after I ran the AC and then cut the engine off for about 10 minutes. Then I returned to the vehicle and cranked it up but the idling RPM was low and then with the AC on it went dead. Then I fired it up again got it running went down the road started my AC. Then as I slowed for a turn came off the gas to turn it went dead. Then stopped it and cut the engine off for 40 minutes. Cranked it up and it ran fine going home. It just does this not very frequently. The idle speed goes low upon cranking it up and does not come up any.

What about Mass Air Flow sensor??? If yes how do you clean this on a 2000 Crown Vic? Any link with pictures?


Need some good advise.

Bert

With those codes, it could be the cat partially plugged. To check to see if the MAF is faulty, unplug it and run the car. If it runs better, the MAF is dirty or defective. To check the cats, check the engine vacuum at idle and the accelerate to about 2000 RPM. The vacuum should drop and then return to almost the same as it was at idle. If not, there could be a restriction in the exhaust.

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Bert

timbogates

Bert, do you have a link or pictures of where the Mass Flow Sensor is located? I think I see it on the incoming intake to the air filter. Please clarify.

Bert

The MAF is in the air cleaner box and the hose to the throttle body connects to it. There's a plug ocnnector to it. To clean it, you need MAF cleaner.

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Bert

timbogates

Bert-- One other note I went back and looked at a post I did a year ago on this same issue. At that time P0157 code was showing for IAC Idle Air Control module. Currently this code is not displaying when I check them. Nevertheless, I have cleaned the MAF sensor - no better. During the time it was doing this I unplugged the connector to the MAF sensor and it did Not get better. Therefore I agree on your suggestion that it is not the MAF. Any other thoughts? It will only do this when the car is hot and I have it cut off for about 10 minutes or 20 and try to crank it again. It goes to a very low idle and you cannot run the AC or it will die. Let the car sit for 1 hour or more. Cranks up and runs fine on a cool - cold engine.

Is it worth trying a new MAF sensor? What are your thoughts on a IAC even though the code now is gone. Only does it in hot weather with the vehicle hot and off only a short period of time. Hey I do appreciate you and others help!!!!

Bert

That shows that the MAF is more than likely okay. The ECT may be sending the wrong signal. Here are the readings for it,
Temp °F Resistance Voltage
176°F 3840Ω 0.75 V
194°F 2800Ω 0.60 V
212°F 2070Ω 0.45 V

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Bert

timbogates

What is the ECT? What are your thoughts on the Idle Air Control Module since it had codes on it about a year ago. THANKS

Bert

ECT = engine coolant sensor. Have you cleaned the IAC?

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Bert

timbogates

What is best to clean the IAC with? Where is it located? Do you have a photo and is it hard to remove? The problem so far only happens while the car is up to running temperature then sits for 15-20 minutes. Then it cranks up at a low idle and wants to die out. When cold no problem.