Just Can't Figureit Out?

arrowshooters · September 9, 2009

98 C1500 w/Rebuilt 5.7 and new MFI. Throwing codes P0420 and

P0430 after trip to the dealer to solve a dieing issue. When they first drove it they only got a code for a loose ground. Somehow on their second test drive the Crank Position Sensor went out causing it to run like c*** above 30 mph. When they checked it no other codes showed up other then the one for the CPS. These codes popped up the next day after I let it warm up a bit, took off down the road and stopped at the first sign. Thing runs like a champ and I have zero starting issues. Does smell a little rich out of the pipe though.

1) I have no other codes.

2) Could the heavy misfiring have killed the cats?

3) Dealer checked fuel presure said around 60, but could I have done something to the fuel system while running the fuel pump off of the test lead under the hood?

4) Tried to test the Coolant Temp. Sensor and it was very hard to get a good connection with the probes but I finally did. At ambiant tempurature I got 1950.

5) If there was anything else "broke" would I not get other codes?

Thanks, this is killing me. What should be a good experience is turning real bad.

arrowshooters · September 9, 2009

Bump

Draenor · September 9, 2009

1) Cats could be clogged

2) The O2 sensor(s) have failed

3) The exhaust has a leak in it before the cat.

arrowshooters · September 9, 2009

1) Cats could be clogged
2) The O2 sensor(s) have failed

3) The exhaust has a leak in it before the cat.

Thanks. Can't hear exhaust leak so I will crawl around and feel. Stealer checked exhaust flow normal. Just find it odd that day after in stealer this pops up.

s_n_a_f_u · September 9, 2009

EGR valve

plugs wires cap rotor you probably did those with the rebuild though

timing off maybe a degree or to i know my regular 350 did not like the stock timing advanced it to 2 degrees and made world of difference

arrowshooters · September 9, 2009

EGR valve
plugs wires cap rotor you probably did those with the rebuild though

timing off maybe a degree or to i know my regular 350 did not like the stock timing advanced it to 2 degrees and made world of difference

EGR Valve hmmmmm. I had to use the old gasket because I could not find a new one. I sprayed quite a bit of Brake Cleaner there and idle did not change though.