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papasmurf · 11-22-2024, 07:53 PM

on. I tried the start the car about an hour later after having success without the clamp on the vac line and it ran for about 1 second before dying. I put the clamp back in place and could not get it to start again after many repeated tries. I went to the auto parts store to rent a fuel pressure tester and there was no pressure on the fuel rail. I checked the fuel pump relay and tried jumpering the relay as well but again no luck. I pulled the battery tray and checked the voltage on the big 4 wire plug (fuel pump I am assuming) on the fuel tank and got 12V on one wire and a little less than 5V on another so it seems the relay is working correctly as I measured it the same with the relay and with just the jumper wire. The fuse for C4 was fine as well. As the daylight was dwindling I hooked up the durametric and ran through the system tests. The car failed the secondary air system readiness test as well as the fuel tank ventilation test. I cycled through some of the related activations and the charcoal filter shut off valve I could hear cycling but the fuel evaporative valve activation did not seem to work (send command failed). Does anyone know what the smaller plug on top of the fuel tank is for...it is three wires...these were nibbled on as well but were still intact.

11-22-2024, 07:53 PM	#12
papasmurf Registered User Join Date: Oct 2008 Location: Waco, Texas Posts: 406	I was hoping I had the problem fixed but it seems there is more going on. I tried the start the car about an hour later after having success without the clamp on the vac line and it ran for about 1 second before dying. I put the clamp back in place and could not get it to start again after many repeated tries. I went to the auto parts store to rent a fuel pressure tester and there was no pressure on the fuel rail. I checked the fuel pump relay and tried jumpering the relay as well but again no luck. I pulled the battery tray and checked the voltage on the big 4 wire plug (fuel pump I am assuming) on the fuel tank and got 12V on one wire and a little less than 5V on another so it seems the relay is working correctly as I measured it the same with the relay and with just the jumper wire. The fuse for C4 was fine as well. As the daylight was dwindling I hooked up the durametric and ran through the system tests. The car failed the secondary air system readiness test as well as the fuel tank ventilation test. I cycled through some of the related activations and the charcoal filter shut off valve I could hear cycling but the fuel evaporative valve activation did not seem to work (send command failed). Does anyone know what the smaller plug on top of the fuel tank is for...it is three wires...these were nibbled on as well but were still intact.