GolfGTIforum.co.uk
Model specific boards => Golf mk2 => Topic started by: james_16v on 20 August 2010, 18:07
-
Hi guys.
Just broke down on the way back from work.
Car started kangarooing at 60mph, managed to limp off the a road where it just cut out.
Car will now start but dies straight away.
All vac lines seem intact and the fuel pump primes on first turn off the key.
Any idea?
Cheers
-
Do the usual (I wrote this as a general guideline).
spark or fuel
(http://img101.imageshack.us/img101/9986/spannerselectedee3.png)(http://img70.imageshack.us/img70/3122/spannertp5.png)(http://img70.imageshack.us/img70/3122/spannertp5.png)(http://img70.imageshack.us/img70/3122/spannertp5.png)(http://img70.imageshack.us/img70/3122/spannertp5.png)
this is just for a little guidance with those getting stuck at - my car doesn't start!
check for spark
1) remove fuel pump relay.
2) remove king lead - place near head and check for regular spark. if the king lead sparks evenly, go to 3, if not, go to 4.
3) re-connect the lead and remove a lead from cyl 1 and check for interval spark, if even, go to 5, if not, go to 6.
4) turn the ignition on, then off, there should be a single solitary spark, if there is, go to 7, if not, go to 8.
5) repeat step 3 with the next cylinder.
6) this is either a ht lead, rotor or distributor cap fault.
7) this is either a hall sender or wiring to coil fault.
8 ) this is either a coil pack, hall sender or wiring to coil fault.
coil pack, hall sender or wiring to coil fault
testing the hall sender requires pulling back the rubber boot on the wiring (ensuring it stays connected), connecting a voltmeter to the middle pin and the other end to ground. put the car in 5th gear and rock the car back and forth (around 1-2m) and watch for fluctuation on the voltmeter. if it doesn't change, then replace the hall sender/distributor.
testing the wiring/coil pack is using your voltmeter and common sense (wiggle wires, check for continuity etc.)
ht lead, rotor or distributor cap fault
to test the leads, swap the faulty lead with a known working lead and test again.
to check the distributor cap/rotor, remove and inspect for signs of arc'ing, ensure contacts are clean with plenty of material.
sometimes just replacing parts is the easiest way to test unknown parts (but not necessarily the cheapest).
checking for fuel
1) after testing the spark first, refit the fuel pump relay, crank the engine very briefly (or just flick the ign on/off) and release, you should hear the fuel pump(s) prime. this relies on all wires being connected to the coil pack - without the wiring connected, the fuel pump will not prime (on a k-jet). if it primes, go to 1a), if it doesn't prime, go to 3.
1a) Disconnect plug from main pump under car and repeat #1, you should hear the in-tank pump prime, if it does, go to 2, if not go to 6.
2) fuel flow needs to be tested.
3) remove the fuel relay and bridge the large pins with a suitably crimped piece of fused wire (rated 20a). if you hear the fuel pump running, go to 4, if not, go to 5.
4) your fuel relay is faulty.
5) replace the fuse for the fuel pump, then repeat step 1. if you have got here a second time, go to 6.
6) fuel pump(s) or wiring fault.
fuel flow needs to be tested
i can't be bothered writing fuel flow tests, check your haynes.
fuel pump(s) or wiring fault
you need to use a battery back and suitable wiring to connectors on the fuel pumps themselves to ensure they run. be extremely careful - any spark could start a fire. use your brain, be careful and figure this one out for yourself.
-
ben might be worth adding this to your list:
If pump is heard to prime, disconnect plug from main pump under car and repeat the test, you should hear the in-tank pump prime
If both pumps are working, next I'd replace the fuel filter. ideally you want to get the fuel pressures tested, but unless you have the proper test equipment its a garage job. blocked filter could cause insufficient pressure at the metering head so worthwhile as its cheap n easy.
-
Cheer Ben thats a pretty comprehensive checklist.
Rubjonny - Picked up a fuel filter and replaced it last night but no luck, also tried a new fuel pump relay and went through the electrical system with a fine tooth comb (sparking strongly).
Ive felt it chugging a couple of times in the past few months but its always cleared itself so thought nothing of it.
Underbody pump primes very noisily and if disconnected I can hear the in tank pump prime.
Im convinced its the main pump as the car starts for a second or 2 then cuts out with both pumps connected and does the same with just the lift pump connected.
So im assuming the lift pump is doing all the work and cant supply enough fuel to keep the car running??
Or am I way off!?
-
no way lift pump could supply enough to make a 16v run, id say the main pump is worn and now cant supply mthe required pressure, especially if its loud :)
k-jet needs at least 5.5bar constant fuel pressure in the metering head to work right, so possibly pump can get it going but not maintain pressure?
-
Cheers jon.
Im stumped if its not the pump?
Found one locally thats still on the car but just spoken to the guy and he said its been off the road for 6 years!!!!
Is this likely to be seized etc as its hasnt run for so long?
-
ben might be worth adding this to your list:
If pump is heard to prime, disconnect plug from main pump under car and repeat the test, you should hear the in-tank pump prime
Thanks bud, done ;)
-
ben maybe you should publish your thread as the unofficial haynes manual replacement :grin:
pump may be ok, but ideally you would want to see if the car runs before you buy. plenty of pumps to be had off ebay though
-
Just to wrap this one up...
Main pump was at fault, picked one up locally and its whisper quiet now!
Car back running sweet for now :smiley: