1996 Buick hesitation

My 1996 Buick has a hesitation from a standing start. If you "blip" the throttle, sometimes it will stall. Makes no difference if it's cold or warm.
When parked, if you give it a hard accel it act's like it is starving for gas. It doesn't rev like a engine should. Being that I just bought this car recently I have no history on it. I changed the fuel filter as it was only driven about 1,000 miles in the last year. Ironically, when I put in a can of fuel injector cleaner, it ran just fine. Adding another can on the next tank fill did nothing. It idle's just fine and run's just fine with no "service engine" light ever coming on. The car has 52,000 miles on it and I do believe it was in a wreck at one time with front end damage. I did find a set screw at the base of the accelerator linkage, (a screw in the center of a 8mm nut) so I kicked the idle up with that but then the "service engine" light came on shortly after that and the light went out again after I put the screw back to it's original position. AutoZone hooked up a scanner but the dude screwed it up I think and never got a code out of it. Perhaps I need to do a reest on the ECM? If I pull the PCM fuse, do you do it with the key on or off to clear things? Any other suggestions for me to look for? Thanks
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Sounds like a TPS (throttle sensor) is going.
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Jason Roner
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My guess too. I read some things that you can check this sensor with a multimeter but I have no idea where the TPS is and what to probe. There are something like 3 electrical boxes on the body where the accelerator linkage is.

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TPS is usually on the throttle body and has 3 wires coming out of it. The computer feeds it 5 volts + and one is a ground. The 3rd wire is the output...usually with the throttle closed, it should sit around 0.92 volts (average) and with the throttle all the way open, should sit around 4.5 volts more or less. As you have the digital meter hooked up, ease the throttle open slowly and watch out for any SPIKES in the reading....it supposed to be very smooth climb...if you get spikes while easing the throttle (car off, ignition on) then you have a bad TPS.
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Not very good reading my multimeter. The DVC selector was on 2.5v. I probed the output wire and saw no spikes all the way to wide open. The meter scale is confusing to read as the scales go 10,50,125 and 250 and the same scale is also used for AC voltage readings. When I first probed that wire with the meter set on the 2.5dvc the needle went to the 2 mark and at wide open it went off the scale. I assume I am supposed to read the 0-10 scale on the meter. With that in mind if I described things right, was the initial reading of 2 too high? My meter is an Amprobe AM-2EDP and can be found here for somewhat of a picture. The red scale at the top is the scale for both DCV and ACV. http://www.omnicontrols.com/lists/amprobe3et.html
Again, thanks for your time. Steve
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Yes. But, put it on the 10V scale and do it again. It should be around 0.8V at idle and move smoothly upward as Fusion mentioned. GW
Steve wrote:

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OK, put it on the 10v scale and get about 0.6v closed throttle and 4v wide open throttle. No spikes that I can see. Thanks, Steve

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