begins missing at 2000rpm

[trx88]

Valve timing and ignition timing are two unrelated things.

what do you mean by this?

 

[94_C/1500]

I'd change the plugs. $12 each for a plug? I'm guessing they were a gimmick of some sort. Do yourself a favor and take them out. Since your truck is '96+ use AC Delco platinum since it originally came with them. My truck is TBI, but I do know the premium distributor caps from Napa aren't good, in my experience. Mine warped and has some serious wear inside and it was only on there about a month. I replaced it with the cheapest one Advance sells and it was fine. But when I went to put the truck on a dyno, I bought a Delphi one. If you are having problems with OE parts, then I suggest looking at the Performance Distributor's website. I believe they sell distributor caps for the '96+ trucks.

 

[94_C/1500]

what do you mean by this?

You had mentioned maybe there was slack in the timing chain causing your timing to be off. The timing chain does not control the ignition timing, it moves the camshaft. Now with that being said, the camshaft does run the distributor. However, if you have a bad timing chain, you will have bigger problems than your ignition being out of spec a little.

 

[trx88]

the timing chain idea i read somewhere.. and im aware that this much slack would cause other ****.

the spark plugs are the platinum ones vortec calls for which might not
have been 12 a piece but they werent cheap comared to the delco r45's or whatever they are
i put a cap on there and then decided to replace the dizzy a week later,
saved the new cap and used the one what come with the distributor.
distributor cap shot **** so i put the older but still brand new one on there
that one shot **** too, leading me to belive that its the cap but i scrubbed up the points and rotor to find that it did not help but it can still have burns and warps and **** so time will tell fellas i will put some effort into it and track down the missing and update everyone.

 

[trx88]

the tps i just put on for giggles and discovered that the old one was trash

 

[bigblue97]

mine had this problem too i put in a new coil. map sensor, cap & button, and tps and that seemed to fix it it was costly but it was worth it! befor i fixed it it wouldnt go over 80 and it lagged a little hope this helps!

 

[trx88]

about the only thing i havent put into this truck is a long block and a map sensor hahahah


so i put a new set of acdelco plugs in there and it solved the random.. now i just have a dead #6 miss

I still need to swap the wire to see if the miss is in the wire or the plug..

some of the plugs had ash on them im hoping its not burning something cause i could have put intake gaskets on there a few months ago when i did the spider upgrade... ill keep posted!

 

[trx88]

well i cant find this missfire i need some help, i have a p0306 random on 6..

swapped plugs with number 8 cleared codes ran then checked still p0306 - not the plug
swapped wires with number 8 cleared codes ran then checked still p0306 - not the wire

plugs are brand new the old ones had some ash that side but all were burnt a bit anyways

not sure where to start need some ideas, inspiration, or advice..

 

[bigblue97]

you could have fouled the plugs from missfiring

 

[trx88]

i put new plugs on it and it fixed the random multiple but now it throws a consistent random 6..

lower intake gasket? bad valve spring?

im still thinking.. this isnt my daily driver

how do i check for a valve problem or if the lower intakes leaking?