GMC Canyon

have an 05 gmc canyon, 5 clylinder truck, love it comfortable ride etc. at 44k miles, starts running rough, mileage gets bad, engine check lite comes on. go to my local mechanic, tells me that the #5 cylinder is miss or not firing. gets down to the cylinder, checks the coil (one for each cyl.) and it tests out ok. decides to change the plugs, even though they should be good for 100k. runs an injector cleaner through the system.

pick up the vehicle, runs good for about 1/2 hour, take back to the shop. so far I’ve got over $300 into the job with parts and labor.

anyone had this problem, with a canyon or the chevy colorado???

please help, thanks…steve

Have your mechanic swap the #5 injector with another cylinder, then see if the miss fire follows the injector.