Sometimes when coming to a stop the car idles up high then when applying the gas pedal the car will sometimes either hesitate or stall completely. Upon restarting oftentimes a small puff of black smoke emerges from the exhaust. I also have higher fuel consumption then I should have. At first I was told by a mechanic that I had a clogged converter. He drilled several holes into it and told me if it helped that I would need to have it replaced that it was indeed clogged. All that has done for me is make the car much louder but driving problems have remained the same, so I guess converter wasn't clogged.
He then told me clogged Fuel Filter which I purchased and changed, did nothing to help.
He then cleaned the contacts on the Mass Airflow Sensor and pointed out that my air filter AND the screen on the Mass Airflow sensor were both black from carbon. He told me that when he cleaned the contact on the sensor that it fixed it, so I bought a new air filter and put it in as well. Within a week the new air filter was blackened again from carbon. Then based on the below-posted Check Engine Codes I retrieved with my Check Engine Light I purchased and installed an Engine Coolant Temperature Sensor, Oxygen Sensor, and Throttle Position Sensor, NONE of which helped anything at all. In fact, the Check Engine Light still spits out those same codes even after those were all changed. The guy then tells me my computer is bad in the car and that it is THINKING that those things are bad and then compensating/adjusting the car's mixture to attempt to correct the problems that it "falsely" sees.
After taking the car elsewhere for a second opinion I was told that was unlikely. They said to change the PCV valve and then if that didn't fix it to change the Mass Airflow Sensor. I bought a PCV valve but I nor anyone I have taken the car to can find it on this car. I finally uncovered via the internet that to change a PCV valve on the 91 3.3L you have to tilt the whole engine forward and it is located UNDER the rear valve cover.
The guy then told me I should check the EGR valve but we couldn't find THAT part either! I stopped on the way home that day at Autozone, Advance, and NAPA and no one could point it out to me on my car and all 3 places said there was no EGR valve in their parts database for this car/engine combo and that they had no way to obtain that part.
My question is, based on all of this plus the codes posted below, is it more likely to be a bad computer, mass airflow sensor, EGR valve, PCV valve, or something else entirely? Keep in mind after changing a lot of the parts on the list below the computer still shows them as being bad. With xmas coming and having 2 children to shop for, we have sunk enough money in playing hit and miss and would prefer not to keep replacing stuff randomly.I can post pics if any are needed.
15 - ECT sensor indicates low temperature, or ECT sensor open
16 - DIS circuit fault
16 - Distributor ignition system or Opti-Spark ignition timing system, low resolution pulse
16 - Missing 2x reference circuit
16 - Transmission speed error(models with 4L60-E transmission or 4.3L S and T vehicle with manual transmission)
16 - System voltage out of range
21 - TPS circuit open, or voltage out of range(probably high)
21 - Grounded wide-open-throttle circuit
43 - ESC unit circuit fault(Buick and Oldsmobile)
43 - TPS out of adjustment
43 - Left oxygen sensor signal rick(1990 and later Cadillac)
43 - Knock sensor signal error
have the same problem?
Monday, October 15th, 2007 AT 11:08 AM