Random Missfire

[vanhal]

on my 98 chevy 5.7 i am getting a code po300 random missfire and i had to replace the rotor it had carbon tracks on it last year i redone my manifold gasket and had to remove the ignition shaft is it posible i am out one tooth and firring between the pins on the cap any info ?? thank you !
.......pete

[hotrod69]

Did U Replace The Cap Also. U Should Not Replace One Without Replacing The Cap Too. As Far As Being Off A Tooth If U Have The Space U Can Clock The Ditributer To Any Tooth U Wish As Long As The Firing Order Lines Up Between The Cap And Rotor And It Is Timed Properly, U Could Have Possibly Clocked 180 Out But Then It Would Either Not Run At All Or It Would Run Like A Garbage Disposal With Ball Bearings In The Trap. The Problem May Be Electronic. Hope This Helps A Little Maybe Gmtech Or Chevyguy Can Give Some Insight To The Problem Also

[mrjohnwayne]

How did you time it when you put it back together. To my knowledge and experience they have to be timed 0 degrees, and you have to do it with a diagnostic computer. It's not hard just tedious.

[gmtech]

If you were a tooth off you would get a 1354 cam shaft / crankshaft correlation code not a po300 random misfire. Could be any igntion component or it could be an injector partially plugged.

[vanhal]

Originally Posted by mrjohnwayne

How did you time it when you put it back together. To my knowledge and experience they have to be timed 0 degrees, and you have to do it with a diagnostic computer. It's not hard just tedious.

well got it done with the help of a gm tech. the crank war put on top dead centre cyl 1 comp.stroke distributor rotor alinged with number 8 pointer that is cast into the distibutor base and it is now runing just fine
the old rotor and cap had a few cracks in it and fired between the cap pins
........ and john wayne thank you for the info ............pete

[hotrod69]

If U Time It From Zero U Are Going To Have A Hard Start Up U Should At Least Start From 10 Degrees Base Timeing And Go +or - From There And Alot Of Domestic Vehicals I Have Noticed There Is A Way To Get To Base Time Manualy With Out A Computer When Base Time Is Set The Computer Should Do The Rest "(i Did Say Should).