Hi all,

 

I've got a 1990 VW Polo Fox (1L with a Weber Carb) which keeps dying on me after a very brief drive. 

 

To set the scene I was driving around town and all of a sudden the engine loses all power, and is then only able to be kept alive by pumping the throttle pedal. Holding the pedal in any position caused it to die, but pumping kept the engine alive though I couldn't get any power out of it. When the engine stalled, I would be able to restart the engine no issues at all but it would promptly die seconds later. 

 

After being recovered home, I've just looked at the car again (about 2 weeks later). Starts first time and then keeps running at idle! Very happy sat on the roadside and keeps running continuously with no throttle pumps. I go to pull away, and it works absolutely fine but after about 100m, it dies out again, as it had done before. Restarting the car again, this cycle continues. 

 

I've previously done work on an '88 Fiat Panda but am new to the Polo so excuse me if this is wrong, but it sounds fuel related? The fuel filter fills up when the engine is off but after start, it remains relatively empty when the engine is running, yet at sat at the roadside the engine still sounds great. It's not exactly squeaky clean inside but I've ordered a new one anyway.  

 

I've attached an image of the outlet side of the fuel pump which has what appears to be some sort of leak, though it was actually fairly dry when I touched it so think it's very slow and maybe negligible? I was able to scrape a small drop off the bottom of the fuel pump and it didn't smell of anything (i.e. no petrol smell); could just be condensation around the outlet?

 

Anyway wanted to check on the forum that buying a fuel pump next is the correct step given it feels like there is a lack of fuel pressure when driving? Does this sound right, or are there other things it could be that I need to check before dropping £65 on a new pump?

 

Thanks all. 

If it keeps running by pushing the gas pedal down and up, that is squirting fuel through accelerator pump jet so petrol is arriving.

 

You could check how well the fuel pump delivers into a container while you crank engine. Might need assistant. Check inline fuel filter. Rusty crud in fuel lines can stop large flow.

 

Me I'd clean the carb jets, check the idle circuit is not inhibited and then for vacuum leaks at the base mount.

Guessing Weber 32TLA on 1 liter. Think this has an idle air bleed not mixture screw. So can't easily pump air backwards through idle circuit into the well.

 

Take off air filter. Get it idling, use the RAC patrolman trick:

Put your hand over the carb inlet and rev it using throttle quadrant to mid speed a few times.

The suction of 40 vacuum cleaners will not pull air but petrol through the carb passageways and jets and wash them clean.

 

Vacuum leak on running car, spray Easy Start around base. If it speeds up there's a leak. (or carb cleaner spray it will slow down).

Bit messy but on none running cold car shaving foam around base. Crank engine, it should bubble at leak point. 

 

Can you smell petrol at the pump? Or tie some tissue around and crank it.

Thanks for your response dvderlm - I'll be sure to give all of these options a go. I can confirm I have the Weber 32TLA.

I'm now hoping it's just a cruddy fuel filter depositing gunk in the jets and that that RAC trick will clean it up - fingers crossed anyway! If that doesn't work I'll also review the vacuum system as you recommended. 

 

Couldn't smell any petrol at the pump yesterday but I'll check with the tissue whether there are any leaks on cranking.

 

I'll get back to you once the new fuel filter arrives.  

Totally agree with everything @dvderlm has put there.

 

my suspicion would be the gasket/rubber block the carb sits on is leaking and sucking air in, making the engine lean out.