Having problems with your 2004 GMC Envoy ?
MY 2004 ENVOY HAS 84600 MILES HAVE DONE OIL CHANGES EVERY 3000 MILES REPLACED TRANS FLUID & FILTER @ 50000MILES HAVE REPLACED FUEL FILTER SEVERAL TIMES IT'S NOT USING ANY OIL BETWEEN OIL CHANGES WHEN AND WHAT SHOULD BE DONE TO TUNE THE ENGINE? RECENTLY STARTED NOT STARTING RIGHT UP AS IT USUALLY DOES. HAVE TO TURN THE KEY OFF AND TRY STARTING AGAIN THEN IT'LL USUALLY START RIGHT UP. THANKS.
When starting your vehicle, cycle the key twice to pump up the fuel pressure. If the vehicle starts like normal, I would replace the fuel filter. Has the fuel filter ever been replaced??? I posted as a solution, but there is no option on this question to get more info.
This could be the signs of the fuel pump going.If you can install a pressure gauge and see if the fuel pressure is up to specs.with the key on and engine off.The specs.are 50 to 57 on the 4.2 and 55 to 62 on the 5.3.Should hold for at least 10 minutes or more.This is with the key on and engine off.Do not cycle the key.As far as tune up.You can check the plugs.They are 100k plugs but they could be worn.I don`t think they are if it runs good once it starts.I`m sure you are changing the air filter also.You seem to take good care of your vehicle.Hope this helps.Good luck.
Repair Help & Product Troubleshooting for 2004 GMC Envoy
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