I bought a set of the regular $1.90 NGK Spark plugs and decided to test all coils and change the plugs just to check.
1. Checked the first and secondary resistance and they all read infinite from 1st to second pin and about 580 ohm from second to first pin.
2.My iridium spark plugs had HUGE gap. I overgapped them myself to 0.054 instead of 44 when I installed them and the car ran GREAT for an year. But now when I pulled them out the gaps were anywhere from 0.055 to 0.068! No way I put in such a big gap.
DIdn't wana regap them and just verified the new cheap NGKs all had 0.044 and put them in. Put about 40 miles in test runs already, highway and street, the problem appears to be gone completely.
However, for those who believe in the 'but dyno', I am strongly convinced that the car pulled noticeably stronger with the overgapped Iridiums I took off. Not to stir anything. Car feels smoother but lost the 'pep' it had. I will drive for a few more days like this to be sure that was the problem and then I will regap again my irridiums to 0.055 and will put them back in.
96blkonblkse strongly suggested plugs. If problem does nto reappear in a couple of days I will pm you for $40 : )
Thanks again for everyone who helped! I still have things to make me scratch my head-- like whats up with the 14.7 AFR under WOT? But the car drives fine in the whole RPM range now under load.
1. Checked the first and secondary resistance and they all read infinite from 1st to second pin and about 580 ohm from second to first pin.
2.My iridium spark plugs had HUGE gap. I overgapped them myself to 0.054 instead of 44 when I installed them and the car ran GREAT for an year. But now when I pulled them out the gaps were anywhere from 0.055 to 0.068! No way I put in such a big gap.
DIdn't wana regap them and just verified the new cheap NGKs all had 0.044 and put them in. Put about 40 miles in test runs already, highway and street, the problem appears to be gone completely.
However, for those who believe in the 'but dyno', I am strongly convinced that the car pulled noticeably stronger with the overgapped Iridiums I took off. Not to stir anything. Car feels smoother but lost the 'pep' it had. I will drive for a few more days like this to be sure that was the problem and then I will regap again my irridiums to 0.055 and will put them back in.
96blkonblkse strongly suggested plugs. If problem does nto reappear in a couple of days I will pm you for $40 : )
Thanks again for everyone who helped! I still have things to make me scratch my head-- like whats up with the 14.7 AFR under WOT? But the car drives fine in the whole RPM range now under load.
Quote:
Ya' know...... this just hit me! Were those results from a post-cat sniffer?Originally Posted by truculent
like whats up with the 14.7 AFR under WOT? But the car drives fine in the whole RPM range now under load.
Awesome you got it worked out
Quote:
Awesome you got it worked out
That was the first time I dynoed a car. They just unplugged my front oxygen sensor and plugged in a wideband.Originally Posted by KRRZ350
Ya' know...... this just hit me! Were those results from a post-cat sniffer?Awesome you got it worked out
As for testing the coilpack, those ohmmeter tests seem inconclusive to me. All they test is infinite resistance and continuity. As if the coil does nothing else. Or does it?
Senior Member
Quote:
As for testing the coilpack, those ohmmeter tests seem inconclusive to me. All they test is infinite resistance and continuity. As if the coil does nothing else. Or does it?
yeah thats how i feel...i dont trust those ohmeter tests when its that "simple".Originally Posted by truculent
That was the first time I dynoed a car. They just unplugged my front oxygen sensor and plugged in a wideband.As for testing the coilpack, those ohmmeter tests seem inconclusive to me. All they test is infinite resistance and continuity. As if the coil does nothing else. Or does it?
They're pretty acccurate for finding breaks in the winding's, but the thing is........ I don't trust them either!! I always just pull the coilpack, reconnect, and plug in an extra spark plug.
Back from the dead:
The problem came back, although not as heavily pronounced and only under full WOT.
Out of ideas. Going to dealer for diagnostics. Hope they find something and I can fix it myself. If not it's gona wait for the spring as it's too cold to work outside already. I am so pissed.
The problem came back, although not as heavily pronounced and only under full WOT.
Out of ideas. Going to dealer for diagnostics. Hope they find something and I can fix it myself. If not it's gona wait for the spring as it's too cold to work outside already. I am so pissed.