: 96 Deville Problems



pfaff563
06-25-10, 11:10 AM
I recently bought a 1996 DeVille with a Northstar engine. Sometimes the car misses, it doesn't idle smoothly, and the "check emissions system" is always on.
The codes are:
PO101 mass air flow sensor out of range
PO147 Oxygen sensor bank 1 sensor 3 heater ckt
PO153 Oxygen sensor signal low-bank 2 sensor 1
PO603 PCM keep alive memory error

He replaced the mass air flow sensor and oxygen sensor bank 2 sensor 1. He's also changed the fuel filter. The car is not running any better. My husband is afraid to keep sinking money in the car in case it has major troubles. He does do all of the mechanical work on our vehicles.

Also, the AC blows out but only hot air. He's tried to recharge it but it won't take any.

Can anyone help us to figure out what to do next?

Ranger
06-25-10, 02:15 PM
Also, the AC blows out but only hot air. He's tried to recharge it but it won't take any.
The compressor is disabled to protect it when low on refrigerant. The codes must be cleared to enable it' so he can add the refrigerant.

What about the Bank 1 Sensor 3 sensor?

pfaff563
06-28-10, 05:12 PM
<<The compressor is disabled to protect it when low on refrigerant. The codes must be cleared to enable it' so he can add the refrigerant. >>

Wow! It worked!!! I cleared the codes and then it took two cans of refrigerant! It blows out cold air now, not hot air like before!!! :thumbsup:

Thank you so much!!!

Next, I'll try replacing the Bank 1 Sensor 3 and see if that helps with the way the car runs and idles.

Sarah

stoveguyy
06-28-10, 06:32 PM
does car run worse when a/c is on now? my car has a funny idle occasionally and it gets worse with the a/c on. i cheaped out and put a used maf on my grand prix. worked fine. they say used electrical parts are a crap shoot but i figured for $25, why not try it? sensor 3 is after cat? does not affect how car runs.

pfaff563
06-29-10, 05:34 PM
It seems to run ok with the AC. I checked the codes this afternoon and got:
PC0171, PC0174, PC0300. I've looked online and can't find what they mean. I have found codes that are P071, etc., without the letter C. Are those the same?

Ranger
06-29-10, 10:58 PM
Find your code definitions here.
http://myweb.accessus.net/~090/dtcobd2.html
P0171 & 174 are lean fuel trim. You have a vacuum leak.

pfaff563
06-30-10, 12:25 AM
So, where do I go from here?

Would the PC0300-engine misfire detected code reflect the vacuum leak problem?

Ranger
06-30-10, 01:28 PM
It might. Start looking for the leak. Cracked or unplugged vacuum hoses. Manifold gasket leak.