csl hesitation - fuel pressure

30csl

30csl

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Well coupers,


To recap, I have been having a problem with my csl where it loses power when going round a left hand bend but not right hand bends. there is also a slight hesitation when accelerating in a straight line.

i finally got round to rigging up a fuel pressure gauge which i could view in the car. At idle the fuel pressure is dead steady at 31-32psi. When on the move and going round a left hand corner the pressure drops in line with the power loss down to 20psi or so!

Is it safe to assume that the problem probably lies with the relay? I have a spare to swap out and check. (under the back seat next to the brain???)

I hope this cures the problem as Im good to go and enjoy the car again then.

Regards,

Rohan
 
Rohan,
maybe a little "off the wall", but if your pressure is dropping that much blasting round LH corners some possibilities:

1) Engine moving around? good mounts?
2) With movement fuel lines getting squashed or kinked, even on a short term basis?
3) Relays and even loose wiring are doubtful
4) grunge in the fuel pick up unit in the tank
5) Pump and "swirl" tank clean and free flowing?
6) pump mounts, wiring etc ok?

Probably whacko, but you never know!
Malc
 
doubt its engine mounts as they are pretty new. the engine does move forward under heavy braking but not excessively so.

fuel tank was cleaned and lined with that paint type stuff, so no rust/dirt to speak off. Will check though.

I dont think a fuel line is getting squashed as their route seems fine but will make sure of that tonight.

As for the tank vent, do you mean the small hose which vents to the outside through the boot floor?


Excited to feel that bit closer to solving the problem!
 
I would try running with out the fuel cap to see if its any better. Just had the same problem with a mates golf gti and my lawn mower. They both would run fine till a load was put on them then they just lost power, the golf some body had fitted a cheap replacement plastic fuel cap and fitting a new one cured the problem 100%. Its some times the simplest things.
marc
 
Let's see. . . the 20 psi confirms its fuel pressure related, but the left hand turn part of it seems screwy. Sure sounds like a fuel pick up problem or a kink in one of the rubber hoses. Have you pulled the pick up out of the tank to inspect it? If not, do that and let us know what you find. It could have a hole that becomes uncovered only on LH turns. I know it sounds unlikely, but I had this problem on a Range Rover I had -- the fuel pump pick up had nearly corroded off -- at half a tank it would run like crap, but only sometimes. Is the "expansion tank" still in place right in front of the fuel pump? How do the hoses look? If they're old, they can kink internally even though they look good on the outside. I had this problem with my old Alfa -- after a few minutes the hose between the pick up and the pump would literally suck itself shut. Easy fix, but hard to figure out. Hope this helps.
 
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