1998 GMC Z -71 acts like it jumped timing
My truck acts like it jumped timing but pull #1 TDC
and rotor button points at #1 on distributor cap, so
it's in time. It lags to start so bad burnt one starter
up. If pedal is held to floor it will crank but won't ifle
May have a fuel pressure issue, or ignition issue. Check to see if you have spark. If so, then there may be a problem with the spider injection, or the fuel pump. Fuel pressure should be checked after replacing the fuel filter, it should be 56 to 63 lbs. at the Schrader Valve.
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