Fuel related non start / hesitation

Hi all,
This is my first post on here. Very good site by the look of it!
I bought a mk1 gti 1.8 '83 last week. I was running very nicely untill last night. It started hesitating on my way home from worthing, when i had to reverse on the driveway, it cut out and then wouldn't start again.
I've been out there this morning to check a few things ( i don't have a lot of knowledge about cars, and this is the first VW i have ever owned )
I undid the fuel filter the out side, and fuel burst out everywhere, so i would assume its not the fuel filter as i thought it might be. I then un did the bolts a little on the pipes on top of the fuel distributor? and a little bit of fuel leaked out of each of them as with the one near the manifold at the front of the engine.
The reason i think it is fuel related is because it didn't backfire once last night when it was hesitating.
The car has had new dizzy cap, rotor arm, leads, plugs and battery recently so can rule them out.
Any ideas would be greatly appriciated.
Thanks in advance

Liam

Wotcha Liam - welcome to the forum.

First thing - get a workshop manual pronto. The fuel system on Golfs stays pressurised for a time even after you've switched the engine off - as you found out when you undid the bolt on the fuel filter.

If you'd done this after letting the engine warm up, you would probably no longer be with us  8O  

Hesitating engine could be a whole range of things - blocked fuel pump, clogged injectors, electrical problems with battery, alternator, distibutor, spark plugs, leaking vacuum hoses, even just a loose connection somewhere. A manual will help you work out which, they include simple tests and will prevent you damaging anything (although most bits of golfs are fairly robust).

It's also definitely worth having a hunt round on the forum for advice given in relation to similar problems, but in the meantime;

• From what you say it sounds like it hesitates when warmed up, so it's probably not just the cold start valve

• Does the car hesitate at all rev ranges? Does it struggle to get to a decent speed, or does it get there eventually?

• How rusty does the fuel filler neck look? this is a fave way for crud to get into the system and block the injectors

• there's a thimble sized filter in some (but not all) fuel pumps that also gets bloked up at the drop of a hat

• the fuel filter may let fuel through (under pressure) but still be clagged up inside. A replacement is cheap (but leave system to de-pressurise, or have cloths to soak up spillages handy)

Just a question - were all the new electrical bits put on to try to sort out the problem? You could ask the seller whether he took it to a garage for this - the garage may be able to tell you what they've already checked. Then you can eliminate the obvious, and whatever remains, however improbable, is the answer Watson (aliens in the cylinder head?)

Hope this helps a bit


Ali Cabrio

First thing to do is to get a manual and take a long hard look at the engine to understand exactly what each component does. The fuel lines you've undone, ideally need their copper washers replaced now. Its also possible to break the banjo bolts if they're done up too tight (lots of people do this, if they leak, eg after taking them off and not renewing the washers!)

Hesitating once warm, in the rev range, could be mixture-related. You'd need a gas analyser to do some of the checks.

Hi, thanks for your replys AliCabrio & paul_c.
It wouldn't start at all today    i've bought a spark plug remover to check them tomorrow, hoping its something not too serious.
I'm not sure if the new bits were to help fix this problem? There were 2 old dizzy caps in the car, so maybe?! The only thing i was told was that the fuel pump relay was dodgy and may need a wiggle if it stoped working!
It started hesitating at 70mph and got progesivly worse for the remaining 3 miles of my journey home. when i pulled up at the house and tried to reverse it stalled and hasn't started since.
Its also had the cam belt done a short while ago and a new water pump. Its done 94,000 miles
Will let you know how i get on tomorrow.
chow for now

Liam

You can bypass the fuel pump relay, with a switch. If this works, and it doesn't work with your fuel pump relay, you know its this!

i'm pretty sure the relay is working ok, because there is the buzzing sound of the fuel pump after i turn the key?

It's still probably worth pulling the relay out to check that it's OK. Sometimes the connections on the relay can become pitted, and prevent it working properly. It may make the fuel pump buzz, but you may still not be getting enough pressure.

Ali

Hello again!
Still no joy! I think i've killed it!  :dontknow:
I discovered this morning that the dizzy cap was on 180 degrees the wrong way? it is now on the right way, but i had to change the leads around. hope i've put them in the right order! I also put new spark plugs in. The bloody thing still wont start! It sounds like it wants to though now. The new battery is not going to take much more!
Here's some pics of the plugs i pulled out, it may help with diagnosis?
Also, some of the car, to let you see what your helping with…

The plugs look dark, but its a really vague way to find a fuel-related fault. Get hold of some 'cold start' spray and see if it starts then. If it is, then its a fuel problem (if your ignition isn't working, then cold start spray still won't start it).

those spark plugs look well past it!  8O

have you got a haynes manual? I'd check your getting the correct voltages to the coil etc… with a voltmeter  
have you checked your getting a nice blue spark from the HT leads?

firing order is 1-3-4-2 so HT leads would go

1–3
  K
2–4

K-King lead

(If your looking straight at it).. well that's how I recall it, could be wrong though, can someone confirm?

This link should help

http://volkswagen.msk.ru/vw_doc/eva2/FU03/ch5.1.2.html

It is 1-3-4-2, and there's a mark on the distributor housing showing where the contact for number one cylinder is.

Liam - what's the general state of the cylinder head and associated piping like? You said that there's a new distributor cap and other new electrical components. Anything else?

It could be that the various vacuum pipes and vents to and from the head are old and cracked and not doing their job properly.

The spark plugs do look a bit shot - it would be easy (and cheap) to get a new set.

Other things worth checking (in order to avoid later hefty repair bills) are;

• state of the cambelt - if this goes you could need a new engine (expensive) - and the belt is cheap and not too difficult to replace

• State of the fan belt - if this goes the cooling system stops working, as does the generator

• How much oil the engine burns (once you've got it running  :mrgreen: ) - this will indicate how worn the engine is. Then you'll have a rough idea how long you have to save up to get a rebore/cylinder head overhaul  :roll:

You will be able to do all of these things yourself with a relatively simple toolkit and a manual (nothing too specialist other than a torque wrench - provided nothing snaps    ).


Ali

Phew! glad I got the firing order right  

it's also worth replacing the oil pump because I've heard bad things when these pack up (which they do).. not a big job to do either

Hi, thanks for that link alicabrio, helped a lot! And thanks for the effort PhillT!  :wink:
Been busy working all week so not had too much time to play with the car. Off Fri Sat Sun Mon & Tues tho so will have plenty of time over the next few days. Been out the again today, bought a brand new dizzy cap and rotor arm, because the other new one was put on the wrong way round by the last owner! bought some cold start and a compression gauge!
Still didn't wanna start with the cold start, but the battery is pretty flat after trying to start it all week, so am charging that up tonight. I found a little bit of oil in the air intake pipe from the airflow meter thingy to the thottle body, is this normal? not a great deal, but definatly some in there.


Will try again tomorrow or sunday with a fully charged battery!
Also…. The comression on turnover was just under 6 bar, anyone know whether this is ok or low?

Cheers

Liam

Compression - bit low but shouldn't prevent you from starting.

It sounds ignition-related.

Double check that at TDC No.1, No.1 spark plug is firing (you'd need to put the engine at TDC then take off the dizzy cover and check the rotor arm is pointing directly at the No.1 position on the cap).

It could be that the ignition leads are fitted wrong, and/or that the timing is way out. There is adjustment available, you slacken off the nut/bolt at the base of the distributor. Set statically for TDC, you can always adjust it later if needs be.

I'd try new spark plugs, make sure they are gapped ok, clean the ignition leads thoroughly and then (using another spark plug) check that you have a healthy spark at each plug (end of lead).

One of the following MUST be wrong:

fuel
achieving compression
valves opening and closing at the right time
ignition timed properly

The Cold start takes care of the fuel. You've checked the compression. The above will have gotten the ignition there. So…..maybe there is something wrong with the valve timing???

Cheers paul,
TDC? what does this stand for?
The leads are definatly on in the right order. firing 1342 from the notch on the dizzy being no. 1.
It had new spark plugs fitted earlier this week.
I will check out the other things you metioned tomorrow or sunday when the battrey is charged up.

Liam

TDC = top dead centre. Check it by taking the plug out of the bellhousing and looking for the notch; or checking the cambelt alignment marks; or by putting a long thin screwdriver into No.1 cylinder and taking the rocker cover off to check that the camshaft lobes for No.1 aren't pressing against the valves, thus meaning that the valves are closed.

Hey there,
 sounds very similar to a problem ive just had.
 the car started hestitating whilst putting load on the engine (driving).
 then one morning it wouldnt start at all.
 
 pulled out a plug to smell alot of petrol, but the plugs were naff, so i got a new set of plugs. still wouldnt start though, pulled the plugs out again to find them soaking in petrol, ie the engine had flooded due to the amount of times i had turned it over to try n start it.

 so i got me dad to give me a tow start and hey presto it started fine.
 so when you get the batt back in there after charging, try giving it a tow start (get to a reasonable speed  and turn the car over, then drop the clutch in second) obviously be careful that you dont fly into the back of the car towing you!!!!!!!
Then if it does start (hopefully it will) take it for a spin to burn off any lingering fuel.

 Best of luck chap.

 Cheers
Jon

It Lives!
Thank you all very much for all your help getting my car running!
It turned out to be the dizzy, undid the bolt on it and adjusted it slighty and now runs fine! Got a massive electric shock tho! Ouch!
Still, It Lives, ha ha!!

Thanks again,

Liam

Congrats mate.
enjoy.

 when you said you "adjusted it slightly" what exactly did you do?

 Cheers
 Jon