I’ve had a 1991 buick skylark for 3 years, just hit 100,000 miles, and for the past few months i’ve been having problems with it stalling out/misfiring when I press the gas, almost like a lawnmower running out of gas, and then catch and go fine. it was only happening at the 3rd gear change,(randomly but only at that change), and then it started happening only at the 2nd gear change. it first happened at the end of a long road trip, and the speedometer and odometer stopped working at the same as well, but have since returned. but now it’s been happening on cross town trips. every time it has happened has been random, and it always corrected itself and was fine. but this last time, it was doing it consistently, at random gear changes and from idle. it finally gave out at a stop sign and it barely stuttered across the intersection, but with the check engine light on and never “catching on” or actually dying/cutting off. I took it to my local shop, and they ran all the computer test and road tested it and told me they couldn’t find anything wrong. they tested the fuel pump, which had good pressure. They mentioned it might be the module, but were honest and didn’t want to charge me for something they couldn’t tell was actually wrong. any clue?
Check to see if any codes are stored in the computer.
Here’s how to do that.
Tester
Unfortunately, those ODB-I systems don’t diagnose much. The car sounds like it is bogging on acceleration and a bad TPS could do this. I’d use a multimeter with a needle dial to check if there are any dead spots in it. Also, with the age, a wire harness issue, like chafed wires, is also possible.