2001 Saturn SL Engine Bucking, Unreponsive Gas Pedal, Erratic Idle
blazinangel
07-30-2011, 01:03 PM
I have had my Saturn for 5 years. When I purchased it, I knew it had some issues. In warm weather, I would say anything over 30 degrees, the idle becomes erratic, going as high as 3500 rpms, and back down to about 1500 rpms. Sometimes it drops so low the engine will stall. The engine also surges and bucks randomly, also only when the ambient air temperature is above 30 degrees. Saturn tried to fix these problem with the previous owner by replacing the tps sensor twice, map sensor twice, and the upstream oxygen sensor once. The car has had a complete engine and transmission overhaul through Saturn.
Since I have owned it, I have had it tested twice, once at Advance Auto Parts and once through a local mechanic with a more sophisticated machine. The car consitently throws a map sensor code although it has been replaced more than once. The codes that were thrown when last checked are as follows:
P0105B-Map circuit
P0108A-Map circuit high
P0122A-TPS low voltage
P0172A-Fuel rich
P01599D- Stall or near stall detected
The recommendations were a new map sensor, or a new tps sensor or possible pcm replacement. Since the first two have been replaced more than once with no improvement, it tells me that they are not the problem. I bought a used computer, but have not yet installed it and paid to have it programmed because of new developments. Just this week in addition to bucking, the gas pedal will randomly become unresponsive as you are driving down the road. There is some resistance in the gas pedal, like pushing on pressurized air, but the engine acts like it is not getting fuel. When I bought the computer, the person who sold it to me said that a downstram o2 sensor can throw a map code. Has anyone else heard this? The downstream O2 sensor has never been replaced. Or does it need the new computer? Almost everything else in the emissions system has been replaced at least once, the wiring had been checked with the last scan as well. I am about to give up, but I can't necessarily afford a different car right now. Any suggestions would be greatly appreciated!
Since I have owned it, I have had it tested twice, once at Advance Auto Parts and once through a local mechanic with a more sophisticated machine. The car consitently throws a map sensor code although it has been replaced more than once. The codes that were thrown when last checked are as follows:
P0105B-Map circuit
P0108A-Map circuit high
P0122A-TPS low voltage
P0172A-Fuel rich
P01599D- Stall or near stall detected
The recommendations were a new map sensor, or a new tps sensor or possible pcm replacement. Since the first two have been replaced more than once with no improvement, it tells me that they are not the problem. I bought a used computer, but have not yet installed it and paid to have it programmed because of new developments. Just this week in addition to bucking, the gas pedal will randomly become unresponsive as you are driving down the road. There is some resistance in the gas pedal, like pushing on pressurized air, but the engine acts like it is not getting fuel. When I bought the computer, the person who sold it to me said that a downstram o2 sensor can throw a map code. Has anyone else heard this? The downstream O2 sensor has never been replaced. Or does it need the new computer? Almost everything else in the emissions system has been replaced at least once, the wiring had been checked with the last scan as well. I am about to give up, but I can't necessarily afford a different car right now. Any suggestions would be greatly appreciated!
yaz4real
08-01-2011, 10:24 AM
Have you ever looked at the ECTS? Engine Control Temperature sensor and its wiring?
Aftermarket sensors ( MAP & TPS ) are said to be of less quality than original and there are recommendations to get replacements from your local junkyard cars.
Continue to look at fuel pressure and filter as a contributing factor along with those sensors at the intake area. Has the throttle body been cleaned out?
And when was the last NGK spark plug, wire change along with a good cleaning of the ignition coils?
Aftermarket sensors ( MAP & TPS ) are said to be of less quality than original and there are recommendations to get replacements from your local junkyard cars.
Continue to look at fuel pressure and filter as a contributing factor along with those sensors at the intake area. Has the throttle body been cleaned out?
And when was the last NGK spark plug, wire change along with a good cleaning of the ignition coils?
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