misfire PO304 with new engine
#51
Same here I was thinking the same thing. Mine was not charging well and whining. took off and had it tested but it would trip their breaker on the machine. Oh and no the cap and rotor did not help.
#52
update on the diagnosis...Called Marshall engines and started a claim, spoke with service tech from Marshalls to further aid in diagnostics..Had to pull valve cover off and back rocker arm nut off and run it to see if there was any change..Guess what? NO change lol ..The reason for this was to see if i needed a shim under the rocker arm bolt thinking the adjustment was too tight..so now i got them scratching heads lmao!! They have never had an issue with roller lifters or these cams,They are installed new not refurbished..So now i have to wait for them to clash heads to see what the next step is.I think the next step they want me to do is check valve springs on cylinder 4...why don't they just admit someone F***** up and send me another engine lol...I will keep you all posted
#53
A bad lifter is not an unheard of issue. I would definitely have them check the cam though. Even with roller lifters, I have seen worn out cam lobes.
#54
Fixed!!
Marshall Engines sent me another engine..Installed it today and my misfire woes are gone woohoo..she runs great..I replaced the torque converter also because it was whining...all is good !! The other engine obviously had a mechanical issue!
#55
oh man, i have a misfire on my 95 S10 pick up "W" vin and i cant figure out what it is. my timing is jumping around all over the place too like yours did... i was hoping you would figure out what was wrong with yours so i could fix mine.... just curious, did you replace your distributor gear at any time? i want to replace my distributor gear because i feel some play in it and also the intake gaskets because i think they leak... im missing antifreeze often, and i smell it too, but it doesnt leak on the floor though.... oh and my motor has been replaced by the dealer in 2003 or 2004 too. only has 20K on the motor and 60K on the body...
#56
i did not have to replace the distributor..I found out the timing variation (jumping around) is normal for these.But im not saying that it cant be your problem..Try the simple tests first before spending money..swap out a spark plug and a wire from a cylinder that isnt misfiring see if it moves to that cylinder..if it doesnt its not that..move on to fuel tests..pull the upper plenum and swap an injector leg that will reach..see if it changes..read through this thread for other ideas as well...good luck!
#57
i did not have to replace the distributor..I found out the timing variation (jumping around) is normal for these.But im not saying that it cant be your problem..Try the simple tests first before spending money..swap out a spark plug and a wire from a cylinder that isnt misfiring see if it moves to that cylinder..if it doesnt its not that..move on to fuel tests..pull the upper plenum and swap an injector leg that will reach..see if it changes..read through this thread for other ideas as well...good luck!
#58
is your computer throwing any codes?
#59
no hard codes... only 2 pending codes which where P1100 and P700 but the were only pending codes that dont cause the engine light to come on. thats the funny thing, my engine light is off. and i made sure the bulb is not burned out either....
you know what would be interesting, to now see if your timing is jumping around with the new motor you just put in now that its running properly. that would deffentaly tell us if its supposed to be jumping around...
you know what would be interesting, to now see if your timing is jumping around with the new motor you just put in now that its running properly. that would deffentaly tell us if its supposed to be jumping around...
#60
the P1100 and P700 codes are transmission codes from the factory i have them too...nothing to worry about..if i get a chance to look at it with a scan tool i will let you know