Hello,

I'm working on my fathers 1997 Monte Carlo. V6, automatic, 126k miles.

It hesitates and loses power from time to time. When it loses power the air conditioner stops outputting cold air. It usually happens when accelerating or under a load. Then, when its not on a heavy load the air comes back on.

I've just replaced the fuel pump and treated the outside of the tank for rust.

It got a little better with the fuel pump but still has the problem.

Any ideas?

Regards,

redbug2

 

I have had A 96 and I still own a 99 Monte My son had the 96 and we experienced about every thing with it, but he was not a gentle driver.
What you are describing is sometimes related to the fuel you may be using. I have a 06 Pontiac Torrent and once the wife put in the E-50 fuel and we had a similar issue with it. We had some Colorado driving in altitudes. Believe it or not the heat will sometimes effect the efficiency of the AC. You most likely would have changed the fuel filter when you did the pump also? Make sure the injectors are clean also. Fuel cleaner I have had good results with Lucas Oil fuel Inj cleaner. Sorry if you have tried all this, you may need more ideas.

 

Yes, I did also change the fuel filter.

Thanks for the ideas. I'll try the Lucas cleaner, good idea.

Regards,

Redbug2

 

a/c automatically turns off if your throttle posistion is to high, ie, heavy acceleration or WOT.

 

This car is still bogging. Maybe I should do a compression check at this point. Is there anything else I should look at?

Any other ideas?

 

^^^ This is why the AC shuts down ^^^


Is the CEL on? If so, have the codes read. You may want to have the history read and see if any codes are pending.


Another possibility is that the catalytic converter may be plugged up. This would cause the car to bog down, hesitate and possibly shift erratically. A shop should be able to run a pressure test on it to determine if it restricted or not.

 

Might have to look into the catalytic converter.

My father brought it over today. I got to drive it finally. When it was cold it was unresponsive. I would put the throttle down from closed to about 3/4 and it would not take any fuel, then, if I punched it it would come araound and take off. It has a real dead spot.

Then, after about 2 miles, when it warmed up, everything was fine.

We replaced the air filter, old one was not great, but I've seen worse.

Bought a manual from pep boys. There are a lot of things to check in there.

Put the code reader in, nothing was reported.

Thanks for your help.

regards,

redbug2

 

Did some web research. Other ideas pointed to the MAF sensor... Replaced that over the weekend. Did the trick, running like new now.

Thanks

 

Ok, thought I would follow up in case anyone else runs into this problem.... Was not the MAF sensor.... Convinced my father to take it to the dealer... Also, I don't know if I mentioned the car has a pretty loud valve tap....

After about a week the dealer called and said it was the Knock Sensor. The sensor was picking up on the valve tap thinking it was pre-ignition and retarding the timing.... That would explain the poor performance... So, they disconnected the knock sensor, hesitation problem solved! They were willing to remove the connection to the sensor because it would not turn on the check engine line... So, worst case now is that the car pings... At 130k miles who cares, cheaper than buying a new car for now. My father says that now it feels like a race car!