New Engine Low on Power
03-20-2013, 05:22 AM
#41
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Join Date: Nov 2004
Location: Tampa FL
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Then it has to be something in the wiring harness to the coil or injector or an issue with the injector itsself. Try swapping the injector to one of the other positions and see if the misfire moves then. If it doesn't you are gonna have to dog the wires in the harness to find the problem.
03-20-2013, 10:20 AM
#42
After scratching my head over this for a while I finally figured it out I think. Since I pretty much ruled out an ignition problem I pulled the fuel rail and injectors last night. I found a few little pieces of what seemed to be silicone sealer (the orange stuff) in the inlet side of a few injectors. I cleaned them out, but the real issue was that the #5 injector wouldnt "click" at all when I applied power to it. I checked all 8 and that was the only one that didnt work. This makes perfect sense since #5 was the cylinder throwing the code (P0305). I ordered a new injector from Rock Auto last night. Hopefully it will come by Friday so I can verify that was the issue all along.
03-20-2013, 10:34 AM
#43
After scratching my head over this for a while I finally figured it out I think. Since I pretty much ruled out an ignition problem I pulled the fuel rail and injectors last night. I found a few little pieces of what seemed to be silicone sealer (the orange stuff) in the inlet side of a few injectors. I cleaned them out, but the real issue was that the #5 injector wouldnt "click" at all when I applied power to it. I checked all 8 and that was the only one that didnt work. This makes perfect sense since #5 was the cylinder throwing the code (P0305). I ordered a new injector from Rock Auto last night. Hopefully it will come by Friday so I can verify that was the issue all along.
Good luck! I must have missed the P0305..I thought you had the P0300 code still. Hope you get it all sorted.
03-28-2013, 02:10 PM
#46
We figured it out. Since the ignition system seemed to check out fine, I focused my attention to the fuel system. I had good fuel pressure to the rail so I decided to pull the injectors. All 8 of them ohmed out fine, and all the driver circuits in the harness worked fine with a noid light. I pulled all the injectors individually and put power to them using a connector from and old LS harness. With 12v to each only one didnt "click". #5 which happened to be the cylinder with the consistant miss and code. I went ahead and ordered a remanufactured injector from Rock Auto (bad idea). Got it, installed it, and got a huge plume of blue smoke out the drivers side exhaust. Turns out the "new" reman injector was stick open and gas washing the cylinder. Long story short I got a GM injector from a local dealer and $140 later she runs like a champ. No miss, no smoke and ready for its final tune and dyno run on Saturday. Ill post up some dyno numbers then. Thanks again guys for all the ideas, support and for sticking with me on this.
glad you got it all sorted out. 