The Cursed T4

[h100vw]

Sometimes the crank pulley for the timing belt wears the the cast in key,so the cam and ignition timing go out far enough to prevent running. Pull the covers off and check and see if the timing marks line up.
Peter

I like this one, happened to me with my G60 Passat. Plenty of spark, lots of fuel, no running.

Check the timing marks.

Can't be the oil pressure cos Matt wouldn't get any compression readings.

Gavin

[Golf Loon]

The bottom pulley does not have marks on, so we made our own by pulling no 1 plug out and feeling with a screwdriver. The Cam pulley has the mark directly upwards which lines up with the mark on the cover.
Then setting up the dissy and should start.

I guess the top could be 180 out, it has apparently been somewhere else for a clutch and to be made to start I hate taking on secondhand problems.

Maybe I`ll try turning the top 180 tomorrow.

I have rebuilt the starter from three dead ones, so hopefullw will be able to start the biach.

I`ll keep you posted.

Matt

[Jmac]

Mate in doing so take the cam cover off and check the lobes are pointing up, incase you are full revolution out. Take the bung out the gearbox bellhousing and line up TDC there, the diamond cut out or O/T lines up with the pointer.
Good luck man
Jmac

[Silver Caravelle]

I've seen enough dead knock sensors and they don't seem to make any difference to normal running and starting except under heavy load and the pinging doesn't stop

Maybe so. However, If I purposely disconnect the knock sensor plugs on my Caravelle, it will not start.

Anyway that it for my suggestions.

[Golf Loon]

Ok, so today I removed the fuel rail as the motor still sounds real fuelly.
Took it apart to change the injectors.

The only replacements I could find have a different colour on the top. From a Golf 3 2L. How different could it be? Whacked em in and no.1 was pouring with fuel, took it all back out again and changed the split o ring. all together and it nearly starts.

Nearly, but not nearly enough. Am wondering if it is the wrong size injectors. I reckon it should start and run rubbish at least. Have all the batterys on charge and am gonna get some aeostart tomorrow and try again.

Anyone have any input?

[gregozedobe]

Anyone have any input?

You have said previously that the spark wasn't real flash. If it is marginal out in the open air then it might not be strong enough when it is in the combustion chamber under high pressure with (possibly too much) fuel in the mix as well.

If it is still getting wet with petrol in the combustion chamber I'd be suspicious of too much fuel, as it should only be getting damp.

I seem to remember a rough spark plug test we used to do with old two stroke motorbikes (always fouling spark plugs) was to hold the spark lead about 2-3 mm away from the top of the spark plug as you cranked it over. If you couldn't see a good, clean spark from the lead to the plug terminal the plug (or the ignition) was suspect. Make sure you hold the plug lead with something very well insulated or you might get a nasty electrical shock.

Failing that then it is (as previously suggested by Jmac), time to go back to first principles, taking nothing for granted and pretending you haven't worked on it at all (ie make sure it is getting air in at the right time, correct amount of fuel, reasonable compression pressure, good spark at the right time and it has to go boom ! )

[Golf Loon]

Got hold of a second hand manifold today.
Changed the throttleboddy, still the same, changed the injector rail and it started, ran for a minute, then stopped.
I reckon we will clean the plugs tomorrow and hopefully it will consistantly start.

[DVR68U]

lol this one has been a pain hey
cheeers brenton

[Golf Loon]

lol this one has been a pain hey
cheeers brenton

Always the way when you take a job on as a favour.

[Golf Loon]

Still no go. Makes spluttering noises but wont go.

Rigged up a crude node light from an LED and the fuel rail is not pulsing correctly. It is intermittant at best.

Has to be ecu. Damn.

Opened up the ecu, no obvious burnt tracks etc.

Anyone got a 1996 on 2L ecu for a transporter?

[gregozedobe]

While you are waiting for an ECU, you might be interested in :

Checking all fuel related electrical connections ?

Checkin for broken (internally) wires ? (Unlikely I know, but easy to check with a multimeter, and imagine how you'd feel if you did get and install another ECU and you still had the problem ? )

[lorraine]

What with your starting problems and my husbands problems with the starter motor on our T4, my husband suggested maybe we should get together and have a big bonfire!!

[Bora Sport]

Someone once told me that if the coil fails it stops the fuel delivery as well. If the spark isn't too flash then maybe the coil is suspect.

[Jmac]

Never heard of the coil doing that ???????????SPark is the output from the coil and that is not measured, only thing linked to the coil via the Ecu is the Hall sender. Im sure that would have been the 1st thing Matt changed.
Loon check the pulse from the centre wire of the hall sender should pulse with crank and the 2 outer should be ground and ign live.
Jmac

[Golf Loon]

Thanks guys. Finally laid this rest today.

T4 dissy is not the same as Golf 3! The Transporter has no crank angle sensor so needs 4 windows in the dissy, the G3 dissy only has 1.
2 Lessons there, 1. assume nothing, no 2 if you change a part and its not that, change it back.

Oli noticed the dissy thing, thanks mate.

Also scored a replacement ecu and the van now starts and drives sweet as.

The original ecu starts the van and makes it hunt up and down and stall sometimes. If I put the replacement one in its all good.

Phew, feels like a weight off my mind and thank God it now works.