monte383sbc

iTrader: (15)

my car is a 98 ls1 t/a and lately my car has started acting up and getting a miss but there is no codes and no dummy lights have come on. it starts to missfire when iam deep into the the throttle and probly above 3000rpm it runs outta power and u can feel it holding back but some times when i nail it in second gear in holds back the feels like it hit a power band at about 5500rpm then pulls fine, then shift into third and starts losing power again, any ideas? it seems like a bad plug or wire, or maybe fuel pump,?

LS6427

iTrader: (2)

Usually that happens when a spark plug wire is touching or banging into an exhaust manifold pipe. It will not happen at idle and down low, usually in the mid to upper rpms during acceleration.

Check them. Cracked plug (ceramic) can be the culprit too.

Lots of other things too:
dirty injector(s)
broken plug wire
dirty fuel filter
leaky injector (leaks bad under acceleration and causes mifires, but not down low)
bad tank of gas
02 sensors that are starting to fail (gotta scan it with a good OBDII scanner to watch them switching while the engine is running)
Dirty MAF (affects it when going WOT)


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monte383sbc

iTrader: (15)

iam acctualy seafoaming it now and iam gunna replace the fuel filter plugs and wire and start there thanks for your help, matt

monte383sbc

iTrader: (15)

problem solved, for some odd reason my plug wire felt like coming loose, car runs like a rapped ape now, thanks

LS6427

iTrader: (2)

cool, its usually something simple when they misfire.

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