8v GTi PROBLEM HELP ***LATEST UPDATE 9th MAY***

Aaaaa

Confucius say - read first, spout later.

hmmm

Cuts out, then refuses to start.

well the warm-up regulator is only supposed to work for a very short time, ditto the aux air valve and cold start injector.

Very short time as in about a minute…tops.

My Cabby starts with a high idle, which goes down in about a minute.

If yours is running for 10 minutes…and then cutting out (inconsistently) it could be;

• something electrical getting hot and malfunctioning (WUR, AAV, ingition circuit) although 10 mins isn't really long enough to get properly hot
• fuel supply giving up (pump not working, injectors clogging up, metering head not responding)
• Intermittent fault that only occurs when you're not looking

Which is what someone said earlier -  :roll:

I would start with a wiggle test to see if anything's loose - like the dizzy, or the timing belt, or anything else that is critical to the engine operating correctly.

Eliminate the obvious stuff like timing being out, dizzy rotating to the wrong position, battery being dead (charge it out of the car).

Then look at the systems individually;

• Electrical - is the dizzy in good condition? Are the sparkplugs past it? how many of the connections actually connect properly? Just going round with some sand paper and cleaning up all the spade connections on the engine will help.

• Fuel - How old is the fuel in the tank? (not that old by the sound of it) When was the fuel filter last replaced? Is fuel getting through? (yes - otherwise it wouldn't run at all) Is enough fuel getting through? (do injector test - carefully) Is enough air getting through? (check for mouse nest in airbox or ancient air filter)

• Vacuum lines - are they all plugged in to the right places? Do any have cracks in? Listen for a hiss - there may well be a hose in the vicinity not plugged in to where it should be.

• Crankcase breather - I'm really not sure about this - but is your crankcase vent (in top of valve/rocker cover) blocked up with crud? I vaguely remember this causing problems to other people. Don't know enough about it to be able to definitely say this is the problem though.

• Exhaust pipe - has some fast-talking LA cop with a cheeky smile popped a banana in your tailpipe so as to effect a sharp getaway while leaving you flatfooted with a stalled car? Just a stab in the dark….

erm - that's a start I suppose.

Ali Cabrio

bloody hell mate!! 8O

lots of ideas. 8)

right, what i'll do is get out to it asap and work my way through all of the suggestions which have been put up so far.

i will then try again and if it fails to run properly i will be much more detailed about what actually happens.

if some of you that have helped so far would prefer i could make a video of it so that you can hear the car for yourselves?? i'd imagine that for alot of you this would be a good idea as you ma recognise a sound which could help point to the problem.

let me know what you all think

thanks

Bren

bren said

if some of you that have helped so far would prefer i could make a video of it so that you can hear the car for yourselves?? i'd imagine that for alot of you this would be a good idea as you ma recognise a sound which could help point to the problem.

The sound of silence would suggest that your engine has stopped running!

seriously though, it could be a number of things.

Try shorting out the fuel relay. When these get warm from being on, they can play up if old and on their way out.

Step 1.
Get two male spade connectors and attach one each end of a short piece of decent cable (High current - 30 amps, so it doesn't melt!).

Step 2.
Run the car until it dies and wont re-start.

Step 3.
Take the relay out. and put this wire in its place. There are only two LARGE terminals sticking out of the relay (the others are all small). It is these large ones you want to bridge, so plug your jumper cable into the relevant holes in the relay board. Your fuel pump circuit will now be constantly live when the ignition is on, rather than just when the engine is running.

If the car starts and runs, then you can safely say your fuel pump relay is knackered.

I had a problem very similar to yours years ago - car would run fine, sometimes for an hour solid, then randomly die and not re-start unless left for a couple of hours. Turned out to be the relay.

Any joy Bren?

ew said

Any joy Bren?

well matey

i'm trying to get hold of a new fuel pump relay at the minute to try to rule that out as the cause so i'm at a bit of a stale mate at the minute.

was in Lincoln on saturday visiting a mate and we went to GSF but they wanted just under ?17 for one!!! and i'm not paying that!

so to be honest champ till thats been tried and tested i'm not taking anything apart or doing the injector test thingy-ma-jiggy

dont worry though, i'll keep you all updated!

Well I got round to sorting this at last.  There were TWO faulty items, The fuel relay (original replacement was faulty) and the WUR.  Now she's purring a treat   Still have a slight electrial gremlin, but hey there's always something, at least it goes now.

How are you getting on?

ew said

Well I got round to sorting this at last.  There were TWO faulty items, The fuel relay (original replacement was faulty) and the WUR.  Now she's purring a treat   Still have a slight electrial gremlin, but hey there's always something, at least it goes now.

How are you getting on?

where in gods name did you get the fuel pump relay from matey?????????!!!!!!!!

let me know asap please :wink:

From GSF, pt no 93592

right, been out on the mk1 today.

started it up, had to keep the revs up myself as the car doesn't seem to be able to keep itself going for the first minute to 2 minutes.

after it was warmed up and running properly i went for a drive around the estate, no problems whatsoever other than a bit of a lumpy idle at junctions.

came back home and the revs have slowly gone down even though it was very warm. so adjusted the idle screw to keep it going.

tok voltage test across the AAV and WUR, only getting 0.21v on the WUR and 0.8v on the AAV, according to the haynes at the WUR its supposed to be 11.5v?!?!

any ideas on this^^^^^?????

anyway, after 1 hour the car still hadn't cut out but i think this was only due to me adjusting the idle screw on tickover. so i turned the engine off and had a cuppa. 10 minutes later went back out to the car and it wouldn't start, there is a spark but nothing else. the car absolutely stinks of petrol

thats the update, as usual ALL HELP AND ADVICE IS APPRECIATED!

thanks

Bren

Sounds like aav def isn't working correctly - whether due to not 12v or actual aav faulty don't know. Try removing it and connecting 12v direct to it. It should slowly close (over around 5 mins) and then slowly open up again once 12v removed…

Have a look in the haynes wiring diagram and see which block the aav wiring comes from on the fuse box. I *think* it is block A (1st one white on nearside of car). Pull it out, have a look in fusebox and connector to see if there is any water, muck etc in there. Try some contact cleaner, allow to dry out properly, then push back in firmly and wiggle about a bit (very technical!)… Sure WUR wiring comes from same block too… Then measure voltage again. This should only affect cold starting though, not hot starting…

If you got spark and you got fuel and the timing is right (as it must be for car to run) then perhaps there is too much fuel - you say it stinks of petrol. Have you pulled the injectors to see if they are leaking. This could cause car to not start when hot as the fuel vapourises and effectivley floods the engine.

Does it start up when cold ok (apart from the revs being too low)?

woZa said

If you got spark and you got fuel and the timing is right (as it must be for car to run) then perhaps there is too much fuel - you say it stinks of petrol. Have you pulled the injectors to see if they are leaking. This could cause car to not start when hot as the fuel vapourises and effectivley floods the engine.

Does it start up when cold ok (apart from the revs being too low)?

hello Woza

yes it starts up ok from cold apart from i have to keep the enigne running by constantly holding the revs higher until the engine is a bit warmer then it seems to stabilize itself.

i haven't checked the injectors as i'm not sure how to, and i dont have a kit to measure fuel pressure etc either. if i take the injectors off do i have to replace the seals? if yes where do i get them from?

i also had a suspicion that the car was possibly flooding itself. due to the petrol smell.

you've raised some good and helpful points matey, dont stop now give me more!

It is a good idea to replace the injector seals - they are only pennies from gsf, main dealer etc… Just need a pair of long nose pliers around the base of the injector, put a rag on the rocker cover (stop it scratching) and prise them out. Spray with wd40 the day before to help ease things up. Should just pop out.

Have a look at prowlers injector test for full details on checking the fueling

http://www.vwgolfmk1.o…5&highlight=injector+test

Cold idling issue is deffo the aav. Fix that and that issue will be sorted. Pretty sure you will find the injectors leaking when ignition off is the hot starting issue. Could possibly cure it by turning the mixture screw anti-clockwise until they stop but then mixture may be too lean at the top end (potentially dangerous). Could be that the injectors need replacing though… ?30 odd each new.

Pull the injectors though and have a look before mewssing with the mixture.

right, time for a update.

i adjusted the camber on the front wheels today and decided to run the mk1 up the road and back to see if the angle would settle.

really struggled to get it started. i had to turn the key but not touch the throttle because everytime i did the engine died instantly.

after about 10mins i finally got it going, i allowed it to warm up so that it was holding the revs up by itself.

i drove up the road and it kept coughing and spluttering, when i pressed the accelerator there was a couple of seconds delay before the car reacted to it.

i started going down the next road to circle back round the block and the revs stuck by itself at 2000(i was in 2nd gear at the time) the engine was making a very strange sound and was really struggling to keep going. by this stage i had lost ALL throttle response. i knew it was going to cut out and sure enough it did just as i was about to come down my road again.

i pushed it home and did all the obvious checks(leads/spark etc etc) i then tried to start it but it wont fire up.

has anyone got ANY ideas what-so-ever as to what it could be?!?!!  

as usual all advice/help/ideas are more than welcome

all the best

Bren

p.s if anyone needs any more info to help with a idea let me know and i'll tell you :wink:

NOW WITH A LINK TO A VIDEO OF THE CAR  SO THAT YOU CAN HEAR IT.

Throttle lag - sounds like inaccurate ignition timing
Cutting out, loss of throttle, etc - dirt/rust in fuel system

Once these are sorted, then a bunch of other checks can be done:
AAV working?
WUR electrics
CSV
clean ignition leads
mixture

etc

keep in mind mate that just before that video was made the car had been running fine for half an hour. just driven round the block in it and it ran like a dream!

this problem only ever happens once the car is hot.

bren said

keep in mind mate that just before that video was made the car had been running fine for half an hour. just driven round the block in it and it ran like a dream!

this problem only ever happens once the car is hot.

Non starting (engine spinning over) is down to one of these 4 things:

No compression
No spark
No fuel
Timing out

Now, since it sometimes runs and sometimes doesn't, I'm going to say the compression is okay. Since you haven't changed anything, I'll also say spark is okay (might be weak if coil is on its way out; or dirty ignition leads; or dodgy plugs - but it will still run).

The injectors open only after seeing an 'opening' pressure of around 3 bar, so small variations in fuel pressure cause large changes in the fuel quantity delivered. A small blockage is enough to send the fuel pressure down, and never open the injectors.

Timing - I only said that because of the throttle response when it drives.

paul_c said

Non starting (engine spinning over) is down to one of these 4 things:

No compression
No spark
No fuel
Timing out

Now, since it sometimes runs and sometimes doesn't, I'm going to say the compression is okay. Since you haven't changed anything, I'll also say spark is okay (might be weak if coil is on its way out; or dirty ignition leads; or dodgy plugs - but it will still run).

The injectors open only after seeing an 'opening' pressure of around 3 bar, so small variations in fuel pressure cause large changes in the fuel quantity delivered. A small blockage is enough to send the fuel pressure down, and never open the injectors.

Timing - I only said that because of the throttle response when it drives.

i getcha matey :wink:

 so it could be something to do with fuel being delivered into the engine via the metering head and injectors once it is hot? some sort of pressure problem?

what should i do to fix this?

tell me the parts and i'll buy them mate!! i'm sick to death of it and just want it running!!! :cry:

heres my 2 cents.

i think that you have a fuel starvation problem. the spark seems to be good so if there is not a mechanical problem within the engine, it must be the fuel.

ii'd start by removing the air filter in the air box under the metering head.
try to raise the flap in the metering head. there should be even resistance from its lowest  rest position( idle) to its highest ( full trottle)and no resistance when  falling back down. as this plate is responsible for the fueling , a stalling engine can be from lack of fuel or too much.

the start problem may be due to the plate not rising when trying to start . the supply from the wur is a choke to the start, but not enough to maintain the running.

also the stalling when it dose start and lack of trottle response or stalling when trottle is pressed is when the engine runs and you add more air you need more fuel, so a sticky plate will not rise,so not adding more fuel, so the mixture leens out too far and the engine stalls.

if the plate in the metering head is sticky there is a procedure where as you can strip it down and renovate it.

i'll guess that you have a faulty fuel filter and some crap from the tank has made its way to the metering head and is jamming the plunger indise the metering head.

thats my 2 cents for 2day.

I agree with Jamez.

Have you tried another metering head on it at all?

Take the plunge and stirp yours down to inspect. I have done mine in the past. There is not a lot to them. Just be careful with the four bolts on the top that are underneath the four allenkey headed bolts. They are set at a specific position to ensure fueling is right for your engine. If you want to remove them, count how many turns out from fully seated they are before you do so. I started removing one and realised that it was not actually "Tight" and might not have been fully seated. I counted 2 1/4 turns from seated on one of the others I think, so set them all back at that position - all was fine.