Maxtastic GXE

I have a intermittent problem with my 1993 VG30E Auto with 172k on it.

This only happens driving on the freeway speeds for about an hour or more, the car will start too slow down and sounds like its "missing" or bogging, I have to keep up the RPM's above 2500 anything under there is little or no throttle response(feels like its running out gas under 2500rpms)...I pull off the freeway and there is a smell of gas and blue/grey smoke(smells rich) coming out of the exhaust. I rev the engine in neutral and and its pops a little, when driving it home.

I popped the hood and the rpms are over the place 500-1200 in park, still smoking this greyish colored smoke and it smells bad. I pulled the plugs,the front one look great,the rear ones look like this...

I disconnected the rear bank wires while the engine was running and the smoking went away. So I let it sit for a few hours,went back out reconnected the wires and it started up ran a little rough and then it was fine?! Fuel injectors perhaps,getting to much fuel in the rear bank and causing the problems and oh yeah mileage has suffered as well even when running fine. I havent ran any codes or fuel pressure tests (dont have the right tools for that) i think the injectors are washing the oil off the cylinder wall and causing the funny smell and blue/grey smoke. I changed the O2 sensor a year ago. What do you guys think? TIA

Levsimus

iTrader: (1)

Blue smoke doesn't bode well, aside from the richness. If the smoke really is tinged blue you're definitely burning some oil which may or may not be contributing to the issue.

I can't honestly provide any input on the bogging as a whole though.

Laevateinn

iTrader: (3)

Are your exhaust manifolds OK? No cracks? Having cracks in the exhaust manifold will suck outside air into the exhaust before the 02 sensor, which then will sense too much oxygen, and concludes it's running lean, then your ECU compensates for it by putting more gas, therefore it will run rich. But running rich will have a black smoke.

That spark plug looks normal to me. Anyway, your local auto parts store should be able to loan you a fuel pressure tester kit. And don't forget to do the compression test as well.

I'm also thinking of a hairline crack in one of the pistons. I think VGs have alum pistons. High combustion temperatures causes the alum to expand, therefore opening the crack