1990 toyota celica gt 5sfe engine. Rough idle, misses erractically, lopes. changed timing belt,wires,rotor button,distributor cap,igniter module,cleaned throttle body,checked cold engine sensor,changed injectors, bench tested map sensor.
After reading nearly all internet postings on this rough idle, loping idle,hesitation at low rpm,I purchased a used map sensor on ebay for 50.00 and all my problems went away. I had bench tested with 5vdc supply etc. the old map sensor and had varying output with varying vacume as one would expect, but after reading a post between two forum members kind of arguing over whether the map was bad or not,I decided to bite the bullet and pay 50.00 for a used map instead of 250.00 for a new one. Purrs like a Kitten.....finally. NOTE: car has 112,000 and none of these things had ever been changed. this problem kind of just forced the issue. all compression checked at approx.195 psi. Fuel pressure checked at 41 psi after already changing the fuel regulator. Changed valve guide seals due to start smoking after setting for a few days. DON'T DISREGARD THE MAP SENSOR.
