Author Topic: Fuel at high rpm prob (Read 4509 times)

Maarten · « **on:** August 20, 2005, 06:13:31 am »

It looks like my pump has problems delivering fuel at higher rpms.. it pulls away nicely from a standstill but when it reaches about 3000rpm (I think) it kinda feels like when you hit the revlimiter in a gasser but then less frequent, I can see the turbopressure dropping 0.2 bar then. When I switch to 2nd gear it pulls again until about the same rpm... :?

My pump started to leak last week so I replaced the throttle bushing and O-ring and modded the governor:

But that didn't solve anything.

Anyone got an idea?

fatmobile · « **Reply #1 on:** August 20, 2005, 11:22:22 pm »

I'm guessing fuel filter. See any air in the fuel line from the filter to the injection pump?
A vacuum gauge will help you spot this problem or rule it out.

Maarten · « **Reply #2 on:** August 21, 2005, 06:19:58 am »

I can't see trhu my fuel lines cause they're black.. But the fuel filter is a good option, though it is only about 7000kms since I replaced it, but I already had a new model filter around so I'm going to swap that today.

Maarten · « **Reply #3 on:** August 21, 2005, 12:15:45 pm »

Ok, I swapped the fuel filter and checked if the throttle is doing the full swing... but now its even worse :? engine runs idle lower than before and does not come anywhere near red-line, I can't even drive 100 meters cause it just dies from lack of fuel I think.

I tried to squeeze the retour, that didn't change anything.. then I squeezed the feeding line from thge filter to the pump, idle went up instantly and when I open the throttle it runs till redline with no problems.

I thightened/replaced all fuel lines and clamps, gonna fill the baby up with some more diesel, you never know if the tankmeter is just busted.

Maarten · « **Reply #4 on:** August 21, 2005, 01:55:53 pm »

Ok.. solved the problem :0

The feeding and retourlines were switched :? I swapped the lines 1 on 1 from the old filter so I think the previous owner fooked things up and I never noticed with the 1600D..

Hammy · « **Reply #5 on:** August 21, 2005, 02:22:18 pm »

Hey Maarten, that's great that you found the problem. Most fuel filters have 'in' and 'out' marked on them. Strange to hear that your fuel lines are all black. Usually, the line between the filter and the IP has a clear part. Did the previous owner replace the line, or is it different in European VW's. :?

Maarten · « **Reply #6 on:** August 21, 2005, 04:30:13 pm »

The filter that was originally on the caddy was a screwfilter on a support without the retourline running back to the filter (runs directly to the plastic line to the tank) so someone who replaced the lines before I got the caddy scrambled things up.

I've got a "heated" filter with the retour thru the filter, the fuel coming from the pump back to the filter heats the incoming fuel so I can run with a higher % veggieoil

AFAIK all fuellines are reinforced black rubber lines overhere.

fatmobile · « **Reply #7 on:** August 22, 2005, 12:04:48 am »

Glad to hear you found the problem.
Kinda sounded like it was starving for fuel.
I've heard of this fuel line mixup happening before.

Maarten · « **Reply #8 on:** August 22, 2005, 05:36:30 am »

Another caddy driver on the dutch forums had the same thing, but for some reason his 1.6TD JR had no problems with it.