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Discussion Starter #1
Recently did a tune up on fiance's car. Did not hesitate before, installed new plugs and wires. Now it has a hesitation at higher rpm's while not under load. If throttle is slowly pressed you can get the rpm's up pretty high w/o hesitation, but if I give it quick burst, or goosing it, it cuts out badly. Took it out on the street and it runs really rough . Old spark plugs were worn but not real bad but the gap on these were around .07 to .08, factory specs are .06. Realizing wear and tear will make the gap larger but by this much? Will resetting gap on plugs a little higher fix the hesitation? Also, in regards to coil packs and ignition module, if one of the components was on the brink of dying, would new plugs and wires put it over the edge?? Help, this car is driving me nuts!
 
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Honestly I think you have crossed 2 wires and have them on the wrong plug. double check the the wires are going to the correct plugs and see if it corrects the problem. I have seen worn plugs gap grown up to .05 so it's normal.
 
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Discussion Starter #3
You may have got the firing order (plug wires) wrong.
 
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I'd go back and check everything you did. Double check the spark plug and spark plug wire part numbers are right for the car. Installing the plugs along the firewall must have been difficult and you could have disturbed a hose or wire back there. Make positively sure that you couldn't have swapped a couple of the plug wires from cylinder to cylinder. You probably removed the air intake ductwork, so you could have an unmetered air leak after the Mass Airflow Sensor at the intake manifold throttle plate connection. Take the ductwork back off again and reinstall it carefully, checking the duct itself for any possible cracks in the duct where air could be entering. A scanner would be helpful in checking error codes that might have been set and to read out the long and short term fuel trim numbers. Actron and Auto XRay both have $150 scanners which may be able to read some of the live data stream information off your OBD-II connector under the steering wheel. AutoZone auto parts stores read the codes as a free service.
Your model car also had some defective catalytic converters. A bad catalytic converter would create exactly the performance problem you describe. It creates excessive exhaust backpressure which mimics an ignition problem. No power when you step on the gas. See the forum discussion link below.
 
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Discussion Starter #5
I'd go back and check everything you did. Double check the spark plug and spark plug wire part numbers are right for the car. Installing the plugs along the firewall must have been difficult and you could have disturbed a hose or wire back there. Make positively sure that you couldn't have swapped a couple of the plug wires from cylinder to cylinder. You probably removed the air intake ductwork, so you could have an unmetered air leak after the Mass Airflow Sensor at the intake manifold throttle plate connection. Take the ductwork back off again and reinstall it carefully, checking the duct itself for any possible cracks in the duct where air could be entering. A scanner would be helpful in checking error codes that might have been set and to read out the long and short term fuel trim numbers. Actron and Auto XRay both have $150 scanners which may be able to read some of the live data stream information off your OBD-II connector under the steering wheel. AutoZone auto parts stores read the codes as a free service.
Your model car also had some defective catalytic converters. A bad catalytic converter would create exactly the performance problem you describe. It creates excessive exhaust backpressure which mimics an ignition problem. No power when you step on the gas. See the forum discussion link below.
 
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