Pushrods4life

Whats up guys as the topic says wierd misfire , cars a 2000 z28 lq9 418ci stroker tuned speed density , after car has reached operating temp its got a wicked miss under load and wont turn past 3k ive check tps, coolant temp sensor , map sensor and wireing , checked fuel pressure and has new fuel filter on it , I also checked all the ground and everything is good and so is the voltage any insight would be greatly appreciated

Thanks, Jose

ACCLR8N

Have you triple checked the plug wires?

2xLS1

iTrader: (25)

Put a data logging scanner on it while it's acting up.

Pushrods4life

Sorry for the late response , just put a fresh set of plugs and taylor wires , still has the miss but it only does it once its been at operating temp for a while I thought it might have been the f.p but its got 60psi rite befor it fonally dies

Pushrods4life

Tried that as well and nothing looks out of the ordinary when I played the data log so im completely at a lose rite now

motoplattinum

can you watch a misfire counter in data?
If not, find someone with a scope and take a spark signature sample when it's cold and running well, then do it again when it's warm and not running well. Compare the 2 and go from there.

Russ K

iTrader: (1)

Misfire detection is disabled in SD mode. The OP will need to enable the Maf for the misfire detection to function.

Russ Kemp

soundengineer

iTrader: (16)

sounds like maybe you have a cracked plug....
it might not show until it warms up and until you got up into midrange rpm is ifts just a very small crack.

try throwing in a different set of plugs

Pushrods4life

Thanks for all the help guys really appreciate it and sorry for the late response been super busy , figured out what it was , the extension for the map sensor wires were very brittle and done with butt connector thanks to a good shop so I was a bit pissed , well ran new wireing and soldered and heat shrinked everything , looks better then factory lol

Thanks again guys