Fuel Starving?

[BEM]

At the recent school at Nelson, I encountered a puzzling problem that I do not know where to begin to start looking. In my A1 Scirocco on the next to the last session on the 1st day. I spun in 13 and ran through some fairly bumpy ground on my way to the front straight. After the session, I came in and got about 5 gal of gas off my neighbor in the paddock (who had blown up and was heading home). On the next session, in the "Oak Tree" and 13 both I suffered heavy backfiring and sputtering (the car acted as if it was starving-even though I had about 2/3 of tank full. The next AM I purchased fresh (92 Octane) gas, and topped off. I still had the same problems at Oak Tree, 13 and by the end of the day in 5. My instructor (who has a lot seat time in VW's at Nelson) had never seen this happen. I have narrowed it down to either I raised up some tank sediment spinning in 13 or bad gas. What do I need to check first? (The pump checks out already) Should I check the fuel pressure next, or get the tank flushed? Has anyone had a similiar problem?

[racer_tim]

Change the fuel filter. That's the first thing I would do. If that doesn't solve the problem, then start with flushing and/or replacing the tank. If you go with a fuel cell instead, that's a whole different issue. Trust me, I went through a full year of developing things to get the FI to work with a cell.



------------------
Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit (Bent)
http://linerud.myvnc.com/racing/index.html

[racer14itc]

You probably broke the pipe that connects the fuel strainer in the bottom of the tank to the tank outlet. This will let the fuel pump suck air even though there is fuel in the tank. This is a very common problem in older VW's w/ stock tanks.

MC
#14 GP VW Scirocco

[BEM]

After several weekends of heavy cursing trying to figure this out, I think found my problem. A short in my ground cable! I guess the lateral movement was enough to pull the short apart, then put it back. I am going to test drive it in an autocross next weekend and hope the problem is gone.