dogsled
LVC Member
2nd Gen V6 was going into failsafe mode with throttle body codes, replacing the throttle body did not fix the issue. It did turn out to be a coil as several here had suggested. It was the rearmost one on the driver side 
woo-hoo!, did not have to pull the intake. There was a tiny bit of oil in the spark plug well. Cleaned that out and replaced coil, problem solved. Will monitor the oil to see if I have another leak or (hopefully) it may have been left over from the recent valve cover gasket replacement job. I'm posting in the hope that this info might help someone else in the future. First a lot of suggestions of "could be a coil" also suggest the passenger rear as the culprit since it is the closest to the PCM. I think that the approx. 25kV discharge from the coil into the block is enough to produce some noise into the PCM that causes it lose track of the TPS regardless of which coil is doing it. That said, check the easy ones first, would have saved me time and money in this case. Second, I received some bad advise claiming that the "miss" I was seeing at 3K rpm in park was due to the rev limiter. WRONG. The rev limiter does kick in at about 3K rpm, but it is gradual and smooth now with the issue solved, does not create anything like a miss and holds the rpm constant at about 3K rpm with no hiccups. It never threw a misfire or coil code, misfire count on my scanner is 0 for all cylinders. Thanks to all the folks that helped me out.
woo-hoo!, did not have to pull the intake. There was a tiny bit of oil in the spark plug well. Cleaned that out and replaced coil, problem solved. Will monitor the oil to see if I have another leak or (hopefully) it may have been left over from the recent valve cover gasket replacement job. I'm posting in the hope that this info might help someone else in the future. First a lot of suggestions of "could be a coil" also suggest the passenger rear as the culprit since it is the closest to the PCM. I think that the approx. 25kV discharge from the coil into the block is enough to produce some noise into the PCM that causes it lose track of the TPS regardless of which coil is doing it. That said, check the easy ones first, would have saved me time and money in this case. Second, I received some bad advise claiming that the "miss" I was seeing at 3K rpm in park was due to the rev limiter. WRONG. The rev limiter does kick in at about 3K rpm, but it is gradual and smooth now with the issue solved, does not create anything like a miss and holds the rpm constant at about 3K rpm with no hiccups. It never threw a misfire or coil code, misfire count on my scanner is 0 for all cylinders. Thanks to all the folks that helped me out.
