i just went to aap today : ( i got 3 codes..intake air temperature (IAT) sensor reading too low, ignition system is grounded, and a mass air circuit problem.. however.. i didnt get these codes til my cat clogged up, its in the shop right now.. can this cause all of the codes above? will it fix it with a new catalytic converter? thanks in advance


also** what is the easiest way to gut the cat or get it off the y-pipe for future reference?

 

Good chance.

 

Easiest way to get it off is a Sawzall...

 

ok cat was just replaced. here it is from the beginning: the car ran awesome for about a half an hour after putting the tranny back in then it started missing and when you pressed the gas it would fall on its face. blows black smoke and fouls the plugs. also the pass side manifold gets hotter than the drivers side.

so far its thrown 4 codes:
-IAT sensor too low temp(23)
-MAF circuit(48)
-EGR circuit (disconnected vacuum line - fixed)(32)
-ICM circuit/grounding(42)

Ive replaced the ICM, and gone as far as taking the MSD dist off and it looks healthy for being on there since march. the MAF, IAT, and ICM all share the same ground but i cant find it.. could this be the problem?[/align]

 

IAT (DTC 23) showing high voltage=low temp, bad IAT or bad sensor ground. Sensor ground comes from PCM, connector B (black connector), pin 16 (black), results in very rich A/F ratio and fouled plugs.

MAF (DTC 48) PCM not getting signal from MAF. Connector B (black connector), pin 19 on PCM,Look for no power to MAF. #5 fuse in Inst panelfuse block (Pink wire on MAF harness).Look for missing chassis ground on BLK/WHT wire on MAF harness. Check voltage between PNK & BLK/WHT wires on harness, should be 12 V battery.

DTC 32, PCM not seeingactivity onConnector B (black connector), pin 5 on PCM, look forshort to ground (white wire)(this signal triggers the Ignition Coil Module, which fires the coil. Check all connectors from Opti to PCM, PCM to Coil Module, Coil module to coil.

There are no shared grounds between these components. All the problems have the black PCM connector in common, may want to disconnect it at the PCM and spray it with connector cleaner (from radio Shack) and put it back good & solid.

PCM has 4 connectors:
A RED
B Black
C Clear
D Blue
Hope this helps.

 

that connector to the pcm is probably the key. thanks pete