importwarrior Posted March 14, 2014 Report Share Posted March 14, 2014 i have been chasing a miss for a few weeks now.it all started with changing the plug wires and rotor and cap.the plugs , rotor and cap fixed my miss when under boost at WOT. but now i have a miss at idle and cruise. after 2 weekends of messing around and checking all that i can.including every ground i can find. i think i have it half way resolved. i replaced all the vac line from the T where the cruise control is to the t-body. i noticed the White Check Valves near the wiper motor do not seem to move smoothlyor freely. thet seem to take A LOT of effort to get them to move. once they are blocking thevacuum it takes a ton to get them to open again. shouldn't they move easily with no force?. I tested them out off thecar with clean hose and the suck test. on a side note i believe the GM MAF is also causing some issues.i need to get another one to test with. i will be doing the TPS reset tomorrow. too dark out. i did test the TPS with an analog meter and it sweeps just fine.i tested the ISC per MIKE C instructions and it seems to be functioning properly. Link to comment Share on other sites More sharing options...
scott87star Posted March 15, 2014 Report Share Posted March 15, 2014 The check valves should move smoothly, years of use have probably crapped them up. Try some carb cleaner. Link to comment Share on other sites More sharing options...
importwarrior Posted March 15, 2014 Author Report Share Posted March 15, 2014 Thank you. I didn't know if it would eat the plastic. Link to comment Share on other sites More sharing options...
Malykaii Posted March 15, 2014 Report Share Posted March 15, 2014 Try brake cleaner first. Its a little less harsh. Link to comment Share on other sites More sharing options...
importwarrior Posted March 15, 2014 Author Report Share Posted March 15, 2014 got the check valves working good. Still missing at cruise and idle. TPStested TPS sweeps fine no issuesset tps properly to .50 volts ISCISC tested fine per Mike C write up tested fine. MAFT and GM MAF sensorMAF tested fine and swapped it out with a brand new MAF sensor with the same results. changed spark plugs cap and rotorstill miss while at idle and cruise. injectors are not dripping when the fuel pressure is up and solid 41 PSI when i turn the car off it holds pressure but eventually drops off in 10 minutes or less. Running out of ideas. don't know what else to check. Link to comment Share on other sites More sharing options...
importwarrior Posted March 16, 2014 Author Report Share Posted March 16, 2014 will a bad turbo cause the car to miss at idle? my turbo just died. Link to comment Share on other sites More sharing options...
importwarrior Posted June 22, 2014 Author Report Share Posted June 22, 2014 new distrubutor cap fixed the ignition problem. now to look at the injector issue and do a compression check. Link to comment Share on other sites More sharing options...
Kenny G Posted July 14, 2014 Report Share Posted July 14, 2014 any update on your issue.... you get it fixed? Link to comment Share on other sites More sharing options...
importwarrior Posted July 14, 2014 Author Report Share Posted July 14, 2014 (edited) yes it all checked out ok. the problem was basically the cap on the distributor was the problem. when looking in to the center of the cap where the brush touches therotor was stuck in flush. the spark was arcing inside the cap to the rotorand not making a solid contact to the rotor. the other problem was i used too much dielectric grease on the sparkplug wire ends. so far so good. pushing 20 PSi. OH! and gaped the plugs down to .028 fixed my hiccup when the car wasfloored and accelerating at mid range RPM. Thought that was caused by the MAF-T. the MAF-T had nothing to dowith it. The spark was getting blown out. Edited July 16, 2014 by importwarrior Link to comment Share on other sites More sharing options...
Kenny G Posted July 15, 2014 Report Share Posted July 15, 2014 good information, thanks! Link to comment Share on other sites More sharing options...
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