I recently did heads-up refresh of my 1999 Tahoe 5.7 4WD that included replacing the intake manifold gaskets (no leaks, but at 130k wanted to get ahead of the problem) as well as upgrading the CFI to MFI. I've put 250 problem-free miles on it since then.
Last night, pulling onto an empty freeway, I decided to, ahem, "blow the carbon out" and stress test my work with a WOT run. I got startled by the sudden intervention of the speed limiter at 98 MPH, but cruised home another 15 miles with no issues. When I parked it, the Tahoe was at about 1/4 full as indicated on the fuel gauge.
This morning, upon trying to start it, the fuel gauge went immediately to the 3 o'clock position and stayed there, and I was unable to connect to the ECM via my OBDII adapter and Torque. Turns out the ECM-1 fuse was blown. I disconnected everything downstream of the ECM-1 fuse (EVRV, EGR solenoid, injector harness) and the fuse is ok and the fuel gauge returns to its normal position only when the injector harness is unplugged.
I measured the resistance across each injector, and it ranges from 12.6 (lowest, Injector# 1) and 13.1 ohms. With the harness disconnected and a new fuse, I measured 12V across each of the pin pairs on the harness side.
Electrically, I'm not seeing what's causing the short every time I key-on with the injectors connected considering the consistency in voltage/resistance I measured on each side. So I'm curious if something may have happened as a result of the fuel-cutoff related to the speed limiter, or if perhaps I have a problem with my ECM? Is there something I need to reset? Any advice would be greatly appreciated.
Last night, pulling onto an empty freeway, I decided to, ahem, "blow the carbon out" and stress test my work with a WOT run. I got startled by the sudden intervention of the speed limiter at 98 MPH, but cruised home another 15 miles with no issues. When I parked it, the Tahoe was at about 1/4 full as indicated on the fuel gauge.
This morning, upon trying to start it, the fuel gauge went immediately to the 3 o'clock position and stayed there, and I was unable to connect to the ECM via my OBDII adapter and Torque. Turns out the ECM-1 fuse was blown. I disconnected everything downstream of the ECM-1 fuse (EVRV, EGR solenoid, injector harness) and the fuse is ok and the fuel gauge returns to its normal position only when the injector harness is unplugged.
I measured the resistance across each injector, and it ranges from 12.6 (lowest, Injector# 1) and 13.1 ohms. With the harness disconnected and a new fuse, I measured 12V across each of the pin pairs on the harness side.
Electrically, I'm not seeing what's causing the short every time I key-on with the injectors connected considering the consistency in voltage/resistance I measured on each side. So I'm curious if something may have happened as a result of the fuel-cutoff related to the speed limiter, or if perhaps I have a problem with my ECM? Is there something I need to reset? Any advice would be greatly appreciated.
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