LT4 LT4 guys need help!

[Kevin Doyle]

Well I got the scanner for the obd 2 and its saying random misfiring cylinders. Well what do you think and where do I start looking 61k on Lt4,Thanks Kevin.

 

[bill81vette]

open your hood up at night and start it up...
see if you can see the sparks jumping.
if you can ,time for new plug wires!

 

[93Rubie]

While your looking for sparks under hood, spary everything down with a mixture of saltwater, that should help to determine if it is wires.

Although, if you have random misfires more than likely something that is needed for the whole Ignition system like the Distributor or Coil or etc...is at fault. Start simple...check plugs and wires first.

 

[gmjunkie]

Well I got the scanner for the obd 2 and its saying random misfiring cylinders. Well what do you think and where do I start looking 61k on Lt4,Thanks Kevin.

Put the scanner in "Misfire Data" mode and find out which cylinders are randomly misfiring!

 

[trourke162]

I had a random misfire on mine. I forget what DTC # it was but the FSM gave reasons for it and one was that the system farted and threw the code out. My Vette was running strong with no ill effects so I cancelled the lite and it has been running strong since. Its been a couple thousand miles so if there is a problem it would have thrown the code out again. If you do not have the set of factory service manuals get them. Well worth the money.

 

[Kevin Doyle]

Took the code out and it came back about 3 miles later it almost feels like a tire is out of balance but I dont think that would cause it to throw a code. Started in dark no arcing do optis usally go completely out or start to act up also,Thanks Kevin.

 

[Kevin Doyle]

Hard to believe!

Well this is hard to believe came home last night and put vette on jack stands pulled all 4 wheels and the driver side rear is all swelled up on one side kinda lop-sided. tire was only 6 years old and 6500 miles firestone firehawk. I dont know if this caused the codes to come up but I am going to replace all o2sensors and put stainless brake lines while it is up and go from there,Kevin.

 

[gmjunkie]

Well this is hard to believe came home last night and put vette on jack stands pulled all 4 wheels and the driver side rear is all swelled up on one side kinda lop-sided. tire was only 6 years old and 6500 miles firestone firehawk. I dont know if this caused the codes to come up but I am going to replace all o2sensors and put stainless brake lines while it is up and go from there,Kevin.

Yeah,6 years is about the life expectancy of a tire,worn or not!!
There are lots of things that can make it throw a Random Mis-Fire code!:L
I believe I'd start with the basics,things like Grounds,Wiring Connections,Injectors,Fuel Pressure,Fuel Filter,Vacuum Hoses,Plugs,Plug Wires,Coil, and did I Mention GROUNDS??:L:L:L
Or you just start throwing Parts at it and eventually find it,or maybe Not!!
But,at least the Parts store would be Happy!!

 

[crmvette]

Yeah,6 years is about the life expectancy of a tire,worn or not!!
There are lots of things that can make it throw a Random Mis-Fire code!:L
I believe I'd start with the basics,things like Grounds,Wiring Connections,Injectors,Fuel Pressure,Fuel Filter,Vacuum Hoses,Plugs,Plug Wires,Coil, and did I Mention GROUNDS??:L:L:L
Or you just start throwing Parts at it and eventually find it,or maybe Not!!
But,at least the Parts store would be Happy!!

if u replaced the dual mass flywheel with single mass this could be the problem

 

[leon]

I would pull all plugs remebering where they went, to see what they look like.