MK1 1800 GTI cab acceleration problem

[Hugebeard]

Hi

Can any1 give me some help from experience as garage can only give me best guess.

OK,

1. At idle the car will only rev up to 3000revs and cuts out (car doesn't stall seems like rev limiter is kicking in?)

2. I can drive for miles at low revs only never going about 2500 revs, when trying to rev higher the engine hits 2500 revs and becomes sluggish.


There is obviously a problem getting adequate fuel thru when I dermand it. The garages best guess is the fuel metering head is corroded.

But thats an expensive guess, what about fuel injectors or fuel pump?

any ideas?

thanks

[Rob mk1]

Have you checked you filler neck for rott, if you have managed to get water in the sytem it could cause you a headache.
i suspect i will be a process of ilimination ie start with the pump(get the flow checked) then work your way forward. R U sure it's a fueling problem could be the hall sender breaking down in the distributor.

Rob

[Flidster_uk]

sounds like the problem i had, rust in your tank syndrome. A possible reason for the fact your car is sluggish when the revs are higher is down to the lift pump in your tank. The lift pump takes fuel from the tank and into the fuel system this is aided by the fuel pump which is located underneath the car towards the rear. The idea being under normal conditions the fuel pump will take fuel from the tank into the system the lift pump increases the rate and helps aid fueling of the car when more power is required, there is a small container that retains a certain amount of fuel, and enables the car to appear quite normal when running, it becomes a problem when you require more power and this containment of fuel is used, the lift pump should keep this full if it is faulty it is only working off the outside fuel pump and creates stuttering and loss of power. I bypassed the fuel lift pump at one point, it will run but lacks power higher up the revs.

metering head is not your problem neither are the injectors, they either work or dont if your car is running at low revs fine then your right to suspect the fuel supply.

check your fuel filler neck if it is a problem then email me, i have covered the whole of the fuel system of a cab.

[Joester]

Perhaps you have one of those awful limited Dizzy Rotor-Arms, with a centrifugal action that retreats the contact head when the revs increase beyond a point.

[greenie]

Hello peeps I hope you sort out the prob.

If it is rust in the tank that has got through from the fuel filler neck it can be the injectors that can be the problem, the rust will go from the tank to the high lift pump through the fuel pump into the meterig head and in he injectors which they will clogg up......

The way to check this is to take the injector out if rust has got through you can see the orangey brown colour of the rust on the injector.......

New injectors cost ?25 each German and Swedish(really need to replace all four) new pump was only ?30

Metering will be a problem well expensive brand new I managed to get a second hand one for ?50, best to check out parts for sales or scrapy's

Hope you get it sorted fella

Andy

[richandhazel]

All good replies there.

It would be well worth checking your rotor arm as it is so quick and easy to do. I've had that before where the revs wouldn't go above 4k and all it turned out to be was a weak spring in the rotor arm (limiter cutting in early).

[SoundillusioN]

Same here, naff rotor arm.   The contacts are supposed to move outwards/inwards depending on the rpm to adjust the timing of the spark (advance/retard and limit).  It may be worth while just changing it for a new one anyway if you haven't done it before or for a long time.  You could be suprised that thats all it is.  a cheap, easy fix. 

[Hugebeard]

Thanks,

Although I have changed the rotor arm got one from Halfords.

Just to give you a bit of history.
 
A month ago the car broke down on me, stalled and came to a stand still.

I gave it a service changing spark plugs,HT leads, distributor head, rotor arm, air filter. (rotor arm and dizzy head and spark plugs from Halfords rest from vw dealer)
 
It ran better. At revs up to 4500 it was perfect, accelerating hard was no problem just cutting out at 4500 revs. I was told get a tune up.
 
I took the car to a rolling road tune up garage and he said that the conditions at idle were fine. When revving to 3000 revs the computer readout was showing results for 6000 revs (sorry I'm not that technical when it comes to cars). He told me it must be my distributor.
 
I got a distributor from the scrappy and replaced. I noticed no difference. Maybe needs a tune-up check. Instead I took the car to VW specialist.
 
After costing me 50 quid for their labour he says it is most likely water has got into the fuel system and corroded the fuel metering head. He asked me if I just recently got the car. I have had the car for 18 months.
 
The only problem I can remember having before breaking down is lack of power at very top end.
My feeling is there has been a problem for a while and its got gradually worse.
 
 The garage sounded quite convincing saying that fuel filter should filter out rust but not water..... blah blah blah.
They did say there was tiny flakes of rust in tank nothing to worry about.


I have looked under the wheel arch and found that the fuel pipe has been changed in the past.



Problem I have is I'm no mechanic so I.m at mercy of Garage unless easy job for me to try. ]



Can anyone recommend a good vw specialist near portsmouth that would be able to give someone better than their best guess?



thanks again