Hey all,
I have a 07 suburban that I just replaced the head gaskets on due to a miss on cylinder 1 & 3. I had previously replaced ecu, plugs wires and coil left me to think it was a leak between cylinders anyways today I got it all back together finally and when I went to start it, now it just cranks no start. It has fuel and compression I dont have a way to check for spark but im assuming the truck is disabled the spark for some reason. Im scratching my head on this. All injectors were plugged back in, in their correct place.

 

so to check for spark, take the coils off of the spark plugs and hold them close to a piece of metal (somewhere on the engine) and have someone turn the engine over and see if you get any spark. if not. that's your problem. if you do get spark go get a compression tester from AutoZone and check to see if you have compression in all 8 cylinders.

 

So it's a bad ground, I jumped ground from coil rails to a known good ground and it fired right up. Apparently this is a fairly common issue on these trucks. Still has a random miss occasionally on 1&3 so dunno about that.

 

try replacing the coils on 1 and 3 and see if that fixes it

 

Save yourself money and swap the coils and wires with other cylinders first and see if miss fires move to them. Check the plugs also. You can swap plugs also.

 

yeah I didn't mean to say it like you had to buy new coils but always swap coils around to see if the problem follows the coils or not. my bad.