odd p0102 code

**myzerman** · 07-15-2009

I have a 2003 grand prix gt with a NONsupercharged 3.8. It was throwing 4-5 codes about a month ago... I replaced the parts called for and then some based on other forum research, including, O2 sensor, MAF sensor, plugs, wires, and cat converter... until I discovered a hole melted in the intake manifold. Still don't understand how that happened. But anyway.
I replaced it and had to re-replace the cat converter b/c it burned up and threw a code from being driven with existing problems.
Everything was fine for about 1000 miles. Now the car barely starts and will only run at an idle or slow acceleration for a few minutes, then stalls. If I unhook the MAF sensor, it runs down the road, but not efficiently. I have check the major vacuum lines and the throttle body intake hose and don't see anything obvious. I do not think it is a MAF problem, just something else disguised as one.
Please help!

**Lawngoose** · 07-15-2009

Do you have a scanner to check MAF frequencies at idle?

Also, check wires for nicks.

**myzerman** · 07-15-2009

I do not have my own scanner or multi-meter. But from what I've read it wouldn't give me a code if it wasn't below the range right? 1200Hz and 11500Hz. I do not see any nicks in the wires.

**blueguy** · 07-15-2009

I say MAF too IMO it causes a lot of funky things to happen...same with the "T" fittings on the vacuum lines...try checking the ones on the left side (passenger side) of the motor on the Lower Intake Manifold...most of the time those got bad from dry rot...my '03's were bad when I bought it and it only had about 42K on it when I changed mine out.

**myzerman** · 07-15-2009

I checked the lines that I think you're talking about. Everything looks good. I did notice that when I shut the car off and listen under the hood, I can hear air seeping from near the power steering unit near the firewall on the driver's side, but I can't see any vacuum lines there. Any idea what that is or if that's normal?

**blueguy** · 07-15-2009

You replaced the LIM gaskets and the UIM and UIM gaskets too? If you did you might have a vacuum leak in the manifolds from something not sealing all the way there too...try spraying some carb cleaner around the motor to check for any smaller leaks that you might not be able to see...

**myzerman** · 07-15-2009

I did not replace the gaskets accept for with the ones from the IM I took off a low mileage Bonneville at a salvage yard. The large gasket on the bottom and the one at the top connecting the plenum were not dis formed or discolored. Perhaps they are not sealing properly? So your saying to spray the carb cleaner around the IM while running to see if it sucks in the fluid? If there is a leak in pressure it has to be after the MAF to create this code, right?

**blueguy** · 07-15-2009

Yeha most likely...and yes spray around the motor while it is running

**myzerman** · 07-15-2009

well... the closest thing I had that i didn't think would cause harm to anything was PB Blaster. It was hard to me to tell if it was getting sucked in or falling to the block with the masses of it. I guess I should try something with a less concentrated spray.