Hello everyone, I am posting in hopes of maybe getting a new set of ideas for my 2000 bravada. I have searched everywhere and determined this could be of some help to me.

Well i have a misfire In the 6th cylinder causing code P0306. This is the only code i have at the moment.

The story of this vehicle is this, I bought it last winter after a roll over in my other car. It ran decent but had a misfire at the time of purchase. Well i went through it and replaced the following

plugs cap and rotor
new distributor - gear was about gone
scfi to mfi conversion
coil
cam sensor
iac - went bad and threw a code
fuel filter
tps - went bad as well
Also have cleaned the Egr valve and passages
Fuel pressure has been tested and is doing fine right around where it needs to be
Maf has been cleaned and verified working order
Vacuum lines have been checked and or replaced
No leaks internal or external on intake plenum
Kinda stumped, and for 2 mechanics that just sucks.. lol

well after i did the mfi conversion it ran like a top, never better, but right about 3 weeks later it started having shifting issues. well the day after the shifting issues started it got the misfire back... So i replaced the distrubutor and cap and rotor again and the shifting was great again but the mis never got better. I cant imagine the new spider went bad already as its a mfi now.. but idk.. Anyone have any ideas?

Sorry this was so long

 

Did you make sure to set the CMP retard and do a CASE relearn after replacing the distributor & CMP sensor? Both of these things combine to allow the PCM to know precisely when to time the spark and both require an enhanced scan tool to perform.

 

No we didnt do that, Didnt know that it needed to be done. What all needs to be done for this?

Also though, why would it have gotten better after the spider, and then just magically start happening again?

 

If the distributor wasn't tightened down properly, it could have moved. There are many possibilities, but you have to diagnose the problem and since you replaced those items without setting them up properly, it is some place to start. As far as 'what all needs to be done', a quick search or two will give you the pertinent details. Both the CASE relearn and CMP retard have been covered.

 

I dont think either of these procedures are going to help me. It was running perfect then went bad without anything being touched. So even though i replaced the cam sensor it shouldnt need to be relearned. because it was acting up before the new one was put it. I could be wrong but im only trying to get my misfire fixed again and it was able to get fixed the first time without any sort of programming.

 

Never mind then... Just trying to eliminate possibilities. I'm not saying that is the source of your problem, but it is a step in the diagnostic direction... If you are unwilling to take the advice, that's your prerogative.

Maybe this thread will help:
P030x - Random/Multiple Cylinder Misfire Detected

Read it all (including the link) and try what you wish.

Good luck with your problem.

 

Damn, Kyle! Lotsa info in those threads. Now I have some ideas for fixing my misfire...