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Won't run unless I pull the fuel pump fuse

Old 11-07-2018, 06:40 AM
Jacob AbuKhader
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Join Date: May 2018
Posts: 155

Originally Posted by Humboldtgrin View Post
Regarding a leaking vacuum line, it will cause a lean issue up until a lean misfire happens. Then raw fuel dumps into the exhaust and tells the O2 sensor itís running rich when itís really lean. Then the DME will try to lean it out more creating more of a lean missfire issue. Also what injectors are you using? Stock 4.5 ohm injectors? If your using low impedance injectors youíll want to use two 1 ohm resistors for each batch fire fuel injector harness. If you use low impedance injectors without resistors it will eventually overheat the DME drivers (there are only two) and basically destroy your DME. Not that this is your issue but you want to rule that out.
After reading this I went out to the car and measured the injectors to verify. I got 4ohms on my multimeter so that indicates that they are indeed stock injectors.

Thanks again for everyone clearing up the vacuum leak symptoms I had them backwards in my head thinking the car would run rich due to overcompensating for fuel. Had a duh moment and realized the car wonít add fuel if the air is unmetered.

Even though testing was good with the meter for the harnesses I pulled back every boot and inspected the connections and they look remarkable compared to what Iíve seen on other posts giving me extra peace of mind that aside from the corrosion on the harness for the speed/red sensors the wiring harness is in great shape and doesnít have any shorts. The DME is testing fine too so Iím about 90% sure the injectors are my issue but I wonít know until I can get them tested at a speed shop. I canít crank them on the car but when they flow test them they will be able to tell me if they were leaking/ have screwed up nozzles or worn springs. Whatever the case may be.
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