Why is my check engine light on GMC Sierra?

It’s the check engine light. It could be a misfiring engine, a broken oxygen sensor or simply a loose gas cap. When you see the check engine light it doesn’t necessarily mean you need to pull the car over to the side of the road and call a tow truck. It does mean you should get the car checked out as soon as possible.

What causes a flashing check engine light on a GMC Sierra?

While a majority of the time, the flashing check engine light is going to be caused by a misfire related to your Sierra’s ignition system or fuel system (as stated above), there are other issues that can cause it. Your timing chain could have jumped .

What are the codes for GMC check engine lights?

P1245Intake Plenum Switchover Valve P1250Early Fuel Evaporation Heater Circuit P1257Supercharger System Overboost P1258Engine Coolant Overtemperature – Protection Mode Active P1260Last Test Failed SCC Or Theft Detected, Vehicle Immobilized

How to troubleshoot a misfire ( GM 4.8L, 5.3L )?

Engine Mechanical: Misfire Troubleshooting. You can find this tutorial in Spanish here: Cómo Diagnosticar y Resolver Una Falla en Cilindro (GM 4.8L, 5.3L, 6.0L) (at: autotecnico-online.com ). The core symptom of a misfire is rough idle.

Is the Check Engine light on a 2004 Silverado Z71?

I checked the chiltons book and it says 05 and up have only filters on the sending units and they are not replaceable. Since yours is an 04 its possible your in the same boat too. My 03 has an inline filter in the frame in the area below the drivers seat. According to the chilton’s book yours should too.

How to fix a PRNDL light on a GMC Truck?

To fix this problem, remove the cluster from the vehicle. Then remove the instrument cluster housings, see the most current repair information for the vehicle you are working on. . Inspect the PC solder joints (circled area) carefully with a magnifying glass. Lookin for cracks in the solder at the top or bottom.