Loss Of Power

[2052006 10]

Did a trackday at Brands Hatch yesterday and towards the end of the evening was suffering from a loss of power at one specific point on the circuit. It was the fastest part - the pit straight (I think it's called that anyway) - just after a long right hand corner. Having changed into 4th it would "hold back" at about 5k rpm but once it had got to about 5.5k, would be okay again. It didn't misfire or anything like that and didn't do it at any other point on the circuit.

 

However, there was at least 1/4 of a tank left (checked as I refilled shortly after leaving the circuit). I'm wondering if this sounds like fuel starvation as it was just after a long right hander albeit when the symptoms arose I was by that time on the straight? This was the only thing I could think of anyway.

 

Pete

[TaffyTim 6]

Soundd like fuel starvation to me, and thats what I put my stuttering down to when i've been there and had the same symptoms at that point.

 

My oil pressure always drops on that corner too, how was yours?

[2052006 10]

Oil pressure (gti6 engine) seemed fine, tried to keep my eye on it when I was in the passenger seat and a mate was driving. It didn't stutter or anything though, just seemed 'breathless', like some cars do as you approach the redline (such as diesels!), but then it would sort itself and behave normally (ie. not at all breathless as it approached the redline!!)

[Anthony 1,003]

Down to 1/4 tank is certainly plenty low enough to get fuel starvation on many 205's, and a right-hander would move the fuel away from the pump pickup

[2052006 10]

Seems like that's what it must be then, couldn't think of anything else really and couldn't replicate it on the road. Cheers.

[Cameron 16]

Definitely fuel starvation, I get issues in mine with anything below about 2/3rds of a tank!

[welshpug 1,666]

strangely it varies quite a lot, my 205 doesn't suffer any surge till its very low, even lapping Llandow on the orange light!

[Anthony 1,003]

strangely it varies quite a lot, my 205 doesn't suffer any surge till its very low, even lapping Llandow on the orange light!

Yup, MASSIVE variation between different 205's for reasons that I don't fully understand.

 

Good example was when I was at Donington Park a few years back - my 205 was happily lapping with below quarter of a tank, and yet the other 205 that I was driving I was getting surge with 7/8th's of a tank showing. Both cars were 1989 models, both being driven in the same manner, and yet seemingly in terms of surge, they couldn't be more different!

[2052006 10]

Yup, MASSIVE variation between different 205's for reasons that I don't fully understand.

 

Good example was when I was at Donington Park a few years back - my 205 was happily lapping with below quarter of a tank, and yet the other 205 that I was driving I was getting surge with 7/8th's of a tank showing. Both cars were 1989 models, both being driven in the same manner, and yet seemingly in terms of surge, they couldn't be more different!

 

 

So I take it, it's just one of those things with a standard tank and pump? Not worth looking at the pump or replacing it? How do you solve the issue - fuel swirl pot thing?

[Anthony 1,003]

The easiest way is to just keep the tank filled above the point which starts to cause issues with fuel starvation!

 

Things like swirl pots and other solutions will work if you want to run with low fuel levels, but they all bring their own set of downsides.

[2052006 10]

The easiest way is to just keep the tank filled above the point which starts to cause issues with fuel starvation!

 

 

 

Yes, fair point, the best ideas are the most simple!

[Paul_13 212 1 Cars]

I heard to use a ph1 pump and a phase 2 tank.

Phase 1 pump has inbuilt baffle.

Phase 2 tank has inbuilt baffle.

Using best of both really.

 

Could be wrong.