Car cutting out when stopping.

MagicMarker

The mother drives a 97 Polo 1L. It drives fine except when coming to a stop, sometimes the revs get too low and it just cuts out, it doesn't happen too often but can be annoying!

Other times it doesn't actually cut out but threatens too, the rev needle will drop very low for a split second forcing the lights to dim briefly and the battery warning light to come on, but it levels out at around 1000rpm after a few seconds.

Any idea what could be the problem and if it's a DIY job?

Rabidlamb

Might be a choke issue, you may need to raise the idling revs.
There's a screw you normally adjust on the end of the throttle cable.

andyseadog

if its a high miler id say its the fuel pump, only sorted the sister in laws the other week with symptoms like that.

I would have been thinking ignition related, coils or something along those lines, purely a guess though.

tc2010

dirty throttle body.

maybe a split in the crankcase breather pipe but 90% its the throttle

bring it into a VW garage and theyll sort it for about an hours labour

andyseadog

RoverJames wrote: »

I would have been thinking ignition related, coils or something along those lines, purely a guess though.

thats what i thought, replaced coil, dizzy cap, rotor arm, plugs and leads, and still running bad. went to a scrap yard and got a fuel pump and the fella working there said i was very lucky to get one, they were notorious for giving up in the mid 90's polos and ibizas

the merchant

Throttle position sensor I reckon.

Emerson

Having same problem but there was an awful rattle coming from engine.
Battery light comes on sometimes too.

Turns out there was not enough oil left and I'd gone on a long journey, Cork-Dublin return making the chain stretch and now it's loose.

When I'm not reving it threatens to, or does cut out.
Repairing this will cost me too much so I plan on ditching her (98 Primera)

First car given to me for nothing by my bro. Learnt the hard way when it was too late.

tc2010

the crankcase breather pipe vents into the airbox as part of the cumbustion process which in turn covers the throttle body with gunk. common problem

dont just assume the worst

MagicMarker

Thanks for all the suggestions guys, after a bit of googling the throttle body comes up a lot.

tc2010 wrote: »

bring it into a VW garage and theyll sort it for about an hours labour

tbh she paid nothing for the car and it's not really a big deal for her, she does very little mileage and it starts right up after cutting out. But if I can fix it myself then I will give it a shot!

Technoprisoner

try the crank angle sensor..it shouldnt cost you more than 50 quid off the top of my head

Emerson

How are the oil levels out of interest?

tc2010

the throttle might need recalibrating after cleaning. not sure on the polo. defo needs recalibrating on passats etc..

it will confuse the ECU when its able to close easily after cleaning. itll seem like the problem isnt fixed and will still cut out. just drive for a few miles and itll sort it

alternatively get it hooked up to a VagCom in a VW garage and have it done instantly

andyseadog

MagicMarker wrote: »

Thanks for all the suggestions guys, after a bit of googling the throttle body comes up a lot.



tbh she paid nothing for the car and it's not really a big deal for her, she does very little mileage and it starts right up after cutting out. But if I can fix it myself then I will give it a shot!

if its the fuel pump (and im feeling cocky here) it will get progressively worse.

bmw535d

idle control valve!;)

Technoprisoner

andyseadog wrote: »

if its the fuel pump (and im feeling cocky here) it will get progressively worse.

very unlikely to be the fuel pump

Del2005

MagicMarker wrote: »

Thanks for all the suggestions guys, after a bit of googling the throttle body comes up a lot.



tbh she paid nothing for the car and it's not really a big deal for her, she does very little mileage and it starts right up after cutting out. But if I can fix it myself then I will give it a shot!

If she does low mileage them it may just be choked up. Bring it for a blast down the motorway in 2nd or 3rd and it should be OK

andyseadog

Technoprisoner wrote: »

very unlikely to be the fuel pump

id be willing to put on a wager... very confident. like i said, recently at a car (also a 97 1.0 polo) with the exact same symptoms, replaced all the ingition components, throttle body, oxy sensor, blew my brains. it was fuel starvation.

MagicMarker

Del2005 wrote: »

If she does low mileage them it may just be choked up. Bring it for a blast down the motorway in 2nd or 3rd and it should be OK

Na that won't do it, I had been using it myself the last few weeks on the motorway and the problem persists.

Technoprisoner

andyseadog wrote: »

id be willing to put on a wager... very confident. like i said, recently at a car (also a 97 1.0 polo) with the exact same symptoms, replaced all the ingition components, throttle body, oxy sensor, blew my brains. it was fuel starvation.

i havent sold that many fuel pumps for these cars...more throttle bodys and sensors....im not saying that its definatley not your problem just unlikely

andyseadog

Technoprisoner wrote: »

i havent sold that many fuel pumps for these cars...more throttle bodys and sensors....im not saying that its definatley not your problem just unlikely

asuming you work for vw parts then?

when i was visiting scrap yards they all said the fuel pumps for that variety of polo were like hens teeth, and they were.

anyway, impossible to tell without seeing the car really.

Technoprisoner

yes i work in this line...im not saying we dont sell them im just saying we sell more other parts than the fuel pumps

andyseadog

working in a similar role myself :rolleyes: from personal experience we dont get many people approaching the main dealer for parts for a car that age anyway. any stock we have suiting cars of that vintage doesnt get replaced when its sold for fear we'l be lumbered with it.

id be guessing a pump for that polo would be circa 500 from vw? on a car only worth 8-900 unless its available second hand its virtually write off.

MagicMarker

Thanks for all the advice guys, I gave the TB a clean this morning and it seems to have done the job!

tc2010

MagicMarker wrote: »

Thanks for all the advice guys, I gave the TB a clean this morning and it seems to have done the job!

nice 1 :pac:

1 nil to me

Matt Simis

tc2010 wrote: »

alternatively get it hooked up to a VagCom in a VW garage and have it done instantly

Would be very handy for the OP to get a VagCom (aka VCDS now) and just read what the ECU sees as the error. I would think dirty TB or split intake hose, both can be determined with visual inspection too.

EDIT: Dammit, I swear I didnt read the last post before posting that!

shamwari

OP, everyone has suggested just about everything possible here as being a possible or potential cause, so I won't add to the list.

What I will say is this: I did look at at a Polo which was the same year as yours and doing the same thing. The cause was simply that someone had fitted the wrong spark plugs to the car. And this was discovered after the world and its mother had messed with the car before I looked at it.