Matt Vardaman

I recently bought another Silverado with a 5.3. I had the heads rebuilt. It had a blown head gasket when I bought it. So I installed the heads with new gaskets and arp bolts. I put everything back together with new bolts everywhere. I first started it up last night and the number 2 cylinder is dead. I swapped coils, have new wires and spark plugs. I believe it’s the lifter on the exhaust, it pops and backfires a little when you give it some throttle. Any suggestions how to verify it’s the lifter???

Also the truck set set up for seven years, and the transmission is stuck in second gear safety mode or limp mode. Any help would be greatly appreciated.

Irish_alley

did you check the compression

Matt Vardaman

I haven’t checked it yet. That’s on the list of things to do tomorrow. I’m going to pull the valve cover and turn it over to see how the rockers move.

Matt Vardaman

I checked the compression today after buying a gauge at harbor freight. All cylinders had 135psi compression which means the block is good. I pulled the valve cover thinking the intake lifter had collapsed. I started it up without the valve cover on and the rocker arms for the #2 cylinder are working fine just like all the rest of the passenger side. I know the ignition coil is good (swapped from another truck) and I have new wires and plugs. So that only leaves the injector for the number 2 cylinder being bad, or stopped up?

If you have any any more suggestions, please let me know.

Irish_alley

either injector or the injector wiring, i know you said the coil is good but did you make sure its firing?

Matt Vardaman

I heard it firing when I pulled the plug wire off while it was running when I located which cylinder was missing. I will use my spark tester tomorrow to verify the spark is good and consistent. If it’s good, then I’ll test #2 injector voltage against another cylinder’s injector voltage. If all that’s good which i believe it is, then I’ll pull the rail and change the injector.

Matt Vardaman

Just to update. After all the tests: compression, verifying rocker arm movement, injector voltage, coilpack, wire, and plug, it end up being trash stopping up the number two injector. I ordered a new set of 8 injectors just to be sure. I will update the thread when it’s up and running right.