Turbo E30 Fuel Issue

[kamotors]

SO the car is a 85 325e with an I head swap, turbo and megasquirt, running NEW 60lb injectors. Car ran great for about 2 weeks and then the external fuel pump went out, Fuel pumps were replaced with an in-tank walboro 255, this fixed the issue and car ran excellent for next 2 days.

After 2 days the car died out on the freeway and would hardly idle, AFR gauge was reading very lean about 17AFR at idle and it would not rev up at all. Car gets progressively leaner as revs increase until it doesn't rev up.

Fuel filter was replaced after the issue and car idles better but will not rev past 4k and revs VERY slow.

Mega squirt was showing fuel load at around 40-50%.

what else could cause this extreme lean condition?

[kamotors]

Also forgot to mention the car takes a very long time to start now.
replaced underhood fuel pump relay and still no progress

When fuel filter was changed NO fuel was in the filter or lines, car sat for 2 weeks prior to the filter change.

[kamotors]

Removed the FPR and fuel lines at the rail and only a drop of fuel was present, car was run just an hour before.

[Bullet Ride]

FPR working correctly?

Check your rubber lines by the filter, maybe one of them got kinked when you changed it.

[jlevie]

A bad FPR is a possibility, but I think it more likely that the culprit is the pump.

[E30_fiend]

I agree with Jim.

With the fact that you've replaced the stock two pump system with a single pump system, the new single pump will be finicky. I know this first hand. What you have to be absolutely certain of is your in tank wiring connections. Don't use butt connectors and solder everything. Those 25+ year old connections don't like to sit at certain angles. Make sure you don't have a lot of slack in the wiring or anything either.

The only true way to runthe single pump in an early model is to get an m42 fuel pump. It has the correct fuel lines conning off of it and it is the right size for the late model walbro pumps.

Good luck man


Taylor

[kamotors]

FIXED, it was the rubber line in between the pump and pump assembly, the line had split in half.

[slow325isedan]

FIXED, it was the rubber line in between the pump and pump assembly, the line had split in half.

I had that same problem when i bought my car, hard to start and ran funny, it was that little line that connects the pump to the hardline