Fuel system troubleshooting
Thread Starter
Pro
Joined: Dec 2001
Posts: 555
Likes: 44
From: Gilbert AZ
Fuel system troubleshooting
This winter I decided it would be a good idea to replace the sending units in both of my tanks, as the gauge wasn't working. I also have the RSI triple pump fuel system and sent the hat/pump assembly back to them as one of the wires had pulled out. They tested the pumps and they are all in good working order.
Today I got the car back together and it started right up and idles perfectly. I don't have a fuel pressure gauge on the car yet, so I am not sure what the fuel pressure it at. I put 5 gallons of gas in the tank to get it going.
The problem I am having is that if I give it gas the RPM's drop and the car wants to die. I can very slowly give it gas and the RPM's will climb. I am trying to figure out where I went wrong...hopefully the easy way through someone else's experience. Anybody have any idea of what I forgot to do when I put it back together?
Today I got the car back together and it started right up and idles perfectly. I don't have a fuel pressure gauge on the car yet, so I am not sure what the fuel pressure it at. I put 5 gallons of gas in the tank to get it going.
The problem I am having is that if I give it gas the RPM's drop and the car wants to die. I can very slowly give it gas and the RPM's will climb. I am trying to figure out where I went wrong...hopefully the easy way through someone else's experience. Anybody have any idea of what I forgot to do when I put it back together?
Team Owner
Joined: Nov 2007
Posts: 24,035
Likes: 2,342
From: Gilbert AZ
Could be a ton of different things. Start with vacuum leaks.
Other than that, if you only touched the fuel stuff, could have a leak in tank with no pressure or low pressure. Have to verify your fuel pressure first.
Other than that, if you only touched the fuel stuff, could have a leak in tank with no pressure or low pressure. Have to verify your fuel pressure first.
Thread Starter
Pro
Joined: Dec 2001
Posts: 555
Likes: 44
From: Gilbert AZ
Thanks Unreal. I did some other work including adding a Mighty Mouse PCV system. I am running a -12AN line from the valve cover to the can and then a 3/8" rubber line to a manifold vacuum source (had to tap the underside of the intake since it is the Victor Jr style intake from GM. I capped the port on the front of the valley the front and put a small filter on the other side of the oil tank.
I removed the cap from the front valley port and the car runs fine now. Prior to adding the PCV system it was vented via a long rubber line to the underside of the car. I am assuming I should go back to that setup but need some advice (or to speak with David at MM for proper routing).
Team Owner
Joined: Nov 2007
Posts: 24,035
Likes: 2,342
From: Gilbert AZ
Vacuum source should be premaf/etc, otherwise you just introduced a big vacuum leak/air source post maf/etc. Vacuum source should be pre-metering device. Basically your sucking in a bunch of extra air that the car doesn't know what to do with.
