Engine Performance problem
1997 Chevy Camaro 6 cyl Two Wheel Drive Automatic 60.000 miles
Ok, I have tried everything that I know to correct a Misfire Cyclinder 5. I replaced plugs, plug wires, coils, ICM, and even had the ECM Flashed but still getting a misfire code. It runs good at first and then after a few minutes, It starts to get alittle sluggish. Gas mileage dropped to 12MPG so I had it tuned up and found several problems.
Heres whats been replaced so far:
Motor Hesco 3.8L 2.5 years old,
Transmission rebuilt 3 Months
EGR 1 Month, changed 3x Thinking I got a bad one from Autozone.
Coils, plugs and Wires and ICM 1 week (tried both MSD and Adelco) Plugs are irthium, Wires are Bosch, Plug 5, changed 3x.
Heres what I am noticing now, Oil Pressure by cold start goes to about 70, after it warms up, It drops to 30 idling and 60 driving (good?). Also notice that it runs alittle hot here in Florida. Straight up at about 210 Degrees. As soon as the temp rises to the middle, the oil pressure drops alittle from 60 to 40 or so by driving.
Car runs like a beast with MSD coils, only notice alittle shuttle between 4rd and overdrive. About 10 Seconds. I cant really feel it missing, but at about 45 mph when you punch it, it boggs down for about 5 seconds.
The P1406 is also driving me bananas. Its what sets off the SES light. The circuit checks out, all tests show that its opening and closing fine. The injectors tested fine so I didnt have them replaced yet.
I had several mechanics look at it at smaller shops, they are either puzzled or trying to get me to bring the car back several times to pay repeated bills. Last thing he changed was the Mass Air Sensor. Said it worked, but then it started all over again, trying to throw parts at it.
Could a Mass air flow sensor make a misfire in 1 cyclinder? And could it be setting off the EGR pindle circuit P01406?
Starting to get worried that this is something major. Please help, I m $6000 down in this car, but really love the 30th aniversary RS. Its a blast to drive. I was planning on driving it to PHL from florida next week. It has 60,000 miles on new motor but 75% is hwy miles back and forth to Ky.