Car dies after short run wont start untill left for awhile

Hi

Weird problem with GOLF GTI 1800, it will only run for a short while then it completely dies whilst driving. Temps are good, fan has gone through a cycle at least, oil temp 87 degrees at cut out point.  No spluttering just complete shut down,  but if I leave to cool for 40mins or so then it will start fine. Engine is good has only 11000 miles since recon fitted, I have replaced fuel pump relay which was faulty thinking that was the prob,  checked for spark when its died so coil seems ok.  I have recently had trouble with the filler neck that rusted but have replaced and cleaned the tank out as best I could with out removing it, since which it has been on a 200 mile journey and back so I am presuming its a new problem.  The only thing that I know of which is a bit strange is the amount of negative pressure that is generated in the fuel tank, strong pull of air when releasing the fuel cap.  I have been running without the seal on fuel cap to stop pressure from forming which seems to work.  Also I can hear the fuel pump prime when turning the ignition even after it has cut out so again I presume this is not the problem.  The only thing I have got to go on is that it is heat related, or pressure build up after some running.

Anybody with any ideas as I have run out.

 

Cheers Cussco

I would do prowler's injector test (see www.vwgolfmk1.co.uk) when it has cut out to verify that you are getting fuel.

As you know you need fuel, spark, compression and timing.  One of those things is failing.

You've verified the spark so the others need to be checked

Have fun and let us know what you find.

Cheers

Rich

Isn't there a tank ventilation thing, which fits into the top of the tank and is a little pipe that comes out underneath the car?

The other thing it could be, is fuel vapourisation - ie your fuel lines are getting too hot, the fuel is turining to gas and then it can't be pumped/metered/delivered to the right place. Are all the heat shields in place, etc? And the fuel lines routed correctly? When it stops, is the heat coming from the engine bay a 'warm/hot' or is it a searing heat, like as if you could roast a turkey in there?

Hi

Thanks I will try testing the injectors next time but I am sure fuel is getting through I can smell it.  Like I said there is spark and recon only done 11000 miles so compression sould be ok and it runs fine until it dies same goes for timing.

Could it be the ignition module above passanger side wing,  could this work intermittently when hot, and at what cost.  Are there any other motors that use the same device.

I tried fast idling outside the house to replicate heat and it died but it fired back up when restarting, but could not get it to do it again.  The only other info I can add at the moment is when its has died it was under heavy load near full throttle but this may have nothing to do with it.

Again any thoughts would be appreciated.

 

i had the exact same symptons about 1month ago and it was because my wife had not put the petrol cap on correctly so if it is on correctly check its sealing and also check the filler neck for holes. the easiest way to test this is once the engines been running for a while take the petrol cap of and see if there is a noise of air pressure escaping (or coming in)

Hi paul_c

Yeah I know of the breather pipes and a valve in top of rear wheel arch, I have checked the tank pipe by blowing down it and it seems fine.  But I am get allot of negative pressure in tank do you think a high enough pressure could stop the fuel from being delivered and make the car cut out.

Cheers Jensen

Hi andunp

Thanks for info.  I have had the dreaded filler neck rusting problem and ever since I replaced it I now get air rushing in.  Once I drove out into the country to give mate a lift, when arrived switch of engine which would not restart again left it awhile to cool still would not start.  I took of fuel cap and releases the pressure and it started first time.  I took of the seal from cap to stop it from sealing.  Funny its seems to work the opposite for me.  

So you golf does produce some pressure which I think is normal. Can you tell me if its positive or negative pressure, and do you think its strong rush or just a small amount?

Cheers Jensen

The petrol tank should be under slight negative pressure i.e. air gets sucked in when the cap is removed.

just my two pence worth, have you cleaned the fuel filters.  I remember reading another post about issues of fuel starvation.


From AL_MK1
"Result…Check your fuel pump!
Take it off the car. On the inlet (tank) side of the pump, there is a small thimble shaped filter. Mine was completely clogged with crap. Cleaned it out replaced and the car ran properly first time!"

Only other thing i can think of is crap is blocking the pick up in the tank, is your fuel filler neck in good shape? and not shreadding Tin worm fragments in to the tank.

Hi

Thanks for info crazyquiff and satelliteone.  

I agree there should be a small amount of negative pressure as I annot see a way that positive pressure could be generated.  The problem with mine is the pressure is on the high side allot of suck.  Again this was not a problem until I changed my rusted through filler neck as the air could escape.

As for the fuel filters I have replaced the filter near head unit 3 times in the last 3 months cutting each one open to check for crud.  The last on being clean.  I still have not taken fuel pump off yet waiting for new one to arrive first.  Do all the fuel pumps have a filter in them mine is 1983 gti and I have read that some do not have this filter.  As for the tank I have clean out as best I can from sender hole, took mesh cylinder out and cleaned this to.

I do believe my problem is with the fuel side of things will investigate further when pump arrives.

Also does anyone know how the breather valve tucked up inside of the top of rear wheel arch should work.?

Thanks again

Jensen

Apparently the original ones fitted by VW did not have the strainer in the feed end from the tank.

Hi

I believe I have solved this wierd problem.  It turns out that the fuel pump was the problem (touch wood).  Been out since changing it and had no probs.  Found a description of a problem that fitted my symtoms.

"EVERY FUEL INJECTED CAR has some type of check valve (NON RETURN VALVE) fitted externally or internally in the main fuel pump. This allows the flow to go only ONE WAY, towards the fuel distributor. The system pressure setting in the fuel distributor keeps holding pressure in the system and fuel line to the fuel pump. A special fitting on the pump has an internal small plastic/stainless steel ball and a compression spring, which punches the ball against the fuel discharge opening of this fitting. The whole fitting with is contents is called a "CHECK VALVE". Check valves can sometimes not seal properly, due to corrosion or build up on the steel ball. Plastic ball check valves tend to distortions due to their plastic properties, becoming like a four cornered ball. This happens mainly from fuel friction of FLOW and PRESSURE and the rising temperature of the low fuel content in the fuel tank. Water in the fuel speeds up corrosion to the compression spring which may completely disintegrate. The sealing ball goes in every direction which can block or restrict the fuel outlet from the fuel pump. The final result of this is total loss of system pressure. The car becomes extremely hard to start in the morning. This also applies for a car which has driven for more than 10 km. A restarting of the engine is almost impossible, as vapour expansion in the fuel distributor from the hot engine pushes the fuel totally back into the fuel tank. To attempt to restart the engine, due to this temporary air lock in the fuel line and in the fuel distributor, will almost drain the battery."

New pump makes hardly any noise compared to old pump.  Got new pump of EBAY ?48 new, pump was advertised as a porsche 944.  Pump smaller in diameter but seems to work fine.

Many thanks for all your help.

Jensen

I had this fault and mine was sorted by an auto-electrician - believe it or not  there was a fault with the amount of ohms running thru the Fuel Pump relay - replaced - and its fine & dandy now.