timing help

[wewsel]

Ok, so I finally got around to hooking my turck up to my laptop. Once it warmed up it settled in at 20 degrees advance timing at idle. Rich readings on both o2 sensors. I know the distributer has been pulled before… The truck runs ok, except for the constant misfire. Got the p0300 code. It's a 1998 sierra with the 5.7. Any other info needed, let me know. I want to get this thing right.

 

[96twodoor]

check this out


http://www.gmt400.com/forum/showthr...ng-and-correctly-setting-a-vortec-distributor

 

[SAATR]

It should set a P1345 if the crank offset isn't plus or minus two degrees of zero. Read the thread Keith linked to and you will have a good understanding of what needs to be done. Can your laptop show you the misfire counters, and which cylinders are missing?

 

[wewsel]

Not with the software I downloaded. If someone knows of a good free download for the software needed to do this right, Please send me a link.

 

[Aloicious]

It should set a P1345 if the crank offset isn't plus or minus two degrees of zero. Read the thread Keith linked to and you will have a good understanding of what needs to be done. Can your laptop show you the misfire counters, and which cylinders are missing?

P1345 will only be thrown if the position is significantly off. the + or - 2* is what spec is, but I've seen engines run at -20* CMP offset without throwing the P1345.

I've never heard of a free software that can read the CMP offset. if the distributor has been pulled and not re-installed to specs with a proper scanner, I can almost guarantee that it's at least a little out of spec. you can take it to a dealer or somewhere with a tech 2 and have them reposition it...however its likely not the only problem if your misfires are bad enough to cause a P0300...unfortunately that is the most vague and hard to track down misfire code...