Suburban Misfire Woe's

**SFSUBURBAN** · 01-06-2009, 07:36 PM

Hello, I have a 96 Suburban with a 5.7 Vortec Motor.I test drove it before I bought it throughly and it seemed to run like a champ.However, It had a misfire on cylinder 4 code the day after I purchased it when I drove it. I decided to do a tune since I recently purchased this truck. I changed the plugs,cap,rotor,wires and fuel filter. The truck idles fine and seems to have power, however I started to get a Random Misfire Code. I checked the wires,cap and rotor and since they were under warranty I replaced them. Now I keep getting a P1345 CMP/CPK Corrolation code. I swapped out the crank sensor to 2 other one's and reset the ECU with my scanner and I keep getting the same code....P1345. Help. What else can I do/check?
Please help any advice will be helpful

Also there's a little wire with some sort of plug or clamp deal on the end of it. It is located under the Intake manifold/box right next to a square wire plug next to the TB. What does this go to...is it supposed to be connected to anything?

**mrfixdit** · 01-06-2009, 07:51 PM

Check your timing if your distributor is advanced too far the cam sensor won't agree with the crank sensor

**SFSUBURBAN** · 01-06-2009, 08:12 PM

I used my scanner to monitor the motor....it says the timing to be -27 degrees and when you press the gas it moves to -18 or so when driving. I did notice that the rotor seems to have a some clockwise/counter clockwise play meaning I can move it back and forth by hand. I do not know if this is normal since this is my first American car in like15 years. On my Honda it's firm I cannot move it.

**MrShorty** · 01-06-2009, 10:42 PM

The correct parameter for checking timing is the cam sensor retard, which is only read by the more expensive scanners. Spec is +/- 2 degrees or something like that.

I'm not sure how much play there should be in the rotor, but I know I've seen many report problem with the distributor gear.

**SFSUBURBAN** · 01-07-2009, 11:44 AM

Thanks for the reply. Is there a fix for the gear/play on the rotor. What about the pigtail that is near the TB.Does that go to anything?

**MrShorty** · 01-07-2009, 02:06 PM

Is there a fix for the gear/play on the rotor.

If the distributor gear is worn, then replace the distributor gear.

**SFSUBURBAN** · 01-13-2009, 02:20 AM

Well I took it to a guy that works at a Chevy dealer. He determined that it was off on the timing. He pulled the Dist. since he believed it to be off by atleast 1 tooth. He moved it and adjusted the timing with the TEC2 deal..I guess we will have to see. So far no hicup's and CEL or in this case SEL. Thanks for the input guys. I will be around lurking, learning and asking questions.