There is a misfire at idle and all driving speeds. I performed a major tune-up, found and repaired exhaust leak at flange between manifold and O2 sensor. I checked for DTC's, none found. Idle, timing, fuel pressure are all in spec. Injectors are operating. Air flow to the engine is fine. Checked vacuum. 20-21"Hg. Vacuum acts normally when revving engine. The car has no EGR valve or MAF. Tested ignition system. Ignition and Pick-up Coil specs are OK. Air gaps in distributor are in spec. I replaced the ignition module(ignitor) with no change. The car runs better at higher rpm's but does have slight hesitation getting up to speed. Cruising at 55mph a misfire is noticed every few seconds. I did not perform a compression test since the vacuum test passed.
Dec 31, 2008 at 3:47 AM
