HELP!!! misssss cant fix
bsduncan
08-12-2009, 11:42 AM
1997 s-15/sonoma 4.3 vortec v6 been setting in a garage for 2 years run great when parked, replaced with a new battery started, had a bad miss, replaced plugs plug wires complete dist. dist.cap,module rotor,,, same miss CAN OBII random/multiple cylinder misfire P0300 cant figure out please HELP !!! Banging head. PS has only 33000 miles
Gabe25
08-12-2009, 03:40 PM
Need alittle more information. What is your VIN Number.
bsduncan
08-14-2009, 10:34 AM
the vin #1gtcs14x8v8521559
Gabe25
08-14-2009, 11:32 AM
Lets rule out the basic’s.
1. Re-check the plug wire firing order.
2. Double check for vacuum leaks
3. Fuel Pressure reading. Key on 61-65 psi. Key off, pressure leak down not
lower then 55psi after 20 minuutes.
4. Check EGR valve for carbon chunks. Re-install with new gasket.
Report back your findings.
1. Re-check the plug wire firing order.
2. Double check for vacuum leaks
3. Fuel Pressure reading. Key on 61-65 psi. Key off, pressure leak down not
lower then 55psi after 20 minuutes.
4. Check EGR valve for carbon chunks. Re-install with new gasket.
Report back your findings.
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