Need some advice on cutting out

[Africatwin]

This is a real intermittent issue so I’m struggling to put my finger on what could be the problem.

The reason I’m posting is because it happened today and wouldn’t restart for about 20min.

It’s a 88 2.1dj - it will start and run with no issues whatsoever… but a few times now and I will say that it happens around the first 5-10min into a journey the engine will
Just die. No splutters no other warnings signs, it just cuts out. It will restart (not today) and usally cutout twice… I’m thinking it’s fuel related. Symptoms of a failing fuel pump maybe? Unfortunately I didn’t have my multimeter on me today when it died and it also died on a busy high street.

[Africatwin]

I’ve done a little more reading.. on the samba there is a thread about a similar issue.. my tach also goes to the floor when it happens so they suggest electrical.. so I’ve gone ahead and cleaned the hall sensor and cabling. Cleaned the pins on the ecu.. which to be honest were really chalked up. Swapped the engine relays also cleaned my earths. I’ll have a run out to stamford hall tomorrow to see if it happens again.

[Africatwin]

I’ve had a run out just to grab some fuel and curiosity.. first 10min - went really well and thought it’s cured, pulled over to refuel. Set off and around 5min into the trip it didn’t cut out this time but I was in 5th around 3000rpm and it started to buck.. it didn’t cut out but it was bucking for about 6 times.

So what I have done has definitely changed something but not cured it.

I have swapped the relays in the engine bay. What symptoms would
I experience if the dodgy relay was now on the ecu side rather than the fuel pump
Side.

[maxstu]

Put the old relays back in for starters. Then try disconnecting the digital idle stabiliser plugs and connect these two plugs together.

[Aidan]

I'm working through intermittent engine management system issue with my DJ powered 1990 South African van - narrowed it down to bad earth connections on the engine, there are 8 earths for the EMS that all earth on the left hand head. In my case with air con they are directly under the compressor so had to first remove that to get decent access to them.
Also whilst repairing the wiring also found damage to the hall sensor wiring where it was routed under the air con compressor bracket and trapped
Basically old hardened wiring and the effects of age and little maintenance and engine vibration leading to chaffing.

Syncrosport website has the wiring diagrams, and engine diagnostics manuals, worth down loading the DJ ones and familiarising yourself with it all if you haven't already.

Failure after running a short while can often be the Transistorised Ignition module TCI, the component on the side of the engine bay with the 7 pin plug sat on a heatsink, adjacent to the coil that is connected to the plastic DLs box which is in turn connected to the hall sender. If the Dls unit is missing (they often are) the two plugs that would go into it will be just connected together - as if you were doing the timing.

A spare TCi is worth carrying, it's the sort of thing to fail and leave you stranded NOS TCi on Ebay

[Africatwin]

Put the old relays back in for starters. Then try disconnecting the digital idle stabiliser plugs and connect these two plugs together.

Thank you.. I’ve just read Aidan’s post aswell. I was going to say. Even though it starts runs and idle really well what would be the reason for Eliminating this.

I'm working through intermittent engine management system issue with my DJ powered 1990 South African van - narrowed it down to bad earth connections on the engine, there are 8 earths for the EMS that all earth on the left hand head. In my case with air con they are directly under the compressor so had to first remove that to get decent access to them.
Also whilst repairing the wiring also found damage to the hall sensor wiring where it was routed under the air con compressor bracket and trapped
Basically old hardened wiring and the effects of age and little maintenance and engine vibration leading to chaffing.

Syncrosport website has the wiring diagrams, and engine diagnostics manuals, worth down loading the DJ ones and familiarising yourself with it all if you haven't already.

Failure after running a short while can often be the Transistorised Ignition module TCI, the component on the side of the engine bay with the 7 pin plug sat on a heatsink, adjacent to the coil that is connected to the plastic DLs box which is in turn connected to the hall sender. If the Dls unit is missing (they often are) the two plugs that would go into it will be just connected together - as if you were doing the timing.

A spare TCi is worth carrying, it's the sort of thing to fail and leave you stranded NOS TCi on Ebay

Thank you for the advice. I may not have got all the earths then so I’ll download the wiring diagrams.

I’ve also ordered a module as well to try.. mine is still connected as when I timed it a few weeks ago I cleaned all the contacts on the module.

So I went for a drive last and I’ve taken two trips this morning. Last night and the second trip today no cutting out but the engine now “bucks” or stutters and just carries on. I don’t know wether to count this as progression or introducing more issues

The work I did was
- clean ecu contacts
- swap relays
- check ignition switch was not loose
- check and clean hall sensor.
- clean earths (maybe not all of them)

I want to say that something I did yesterday has potentially made things better

[Aidan]

The only engine part earthed under the coil is the heater for the crank case gases, all the engine earths go to the left head. There should be an earth from the body to the engine next to them too, as well as the earth strap at the front of the gearbox.

[icosahedron]

Over the years, I've occasionally experienced the same problem and have always solved it by cleaning the AFM potentiometer track. It is now part of my service routine.
 

[Africatwin]

Over the years, I've occasionally experienced the same problem and have always solved it by cleaning the AFM potentiometer track. It is now part of my service routine.
 

Cheers, I do this as part of my service as well

[Africatwin]

So I’m going to try and keep this thread alive until I know it’s fixed. I’ve read so many threads with no actual resolutions.

Cleaned all the earths in the engine compartment that I can find and I’ve swapped out the TCI module and cleaned the idling stabiliser unit.

Only one run so far but Im going to try and take it over short runs over the next couple of weeks to try and replicate the issue.

[silverbullet]

That VW Telefunken TCI is ancient, not as old as the 211 unit that I had fall over recently, but its a Golf 2 part so its as old as your van.
Its just a transistor amplifier that relies on the heat sink for long life, but sooner or later they die.

[Africatwin]

That VW Telefunken TCI is ancient, not as old as the 211 unit that I had fall over recently, but its a Golf 2 part so its as old as your van.
Its just a transistor amplifier that relies on the heat sink for long life, but sooner or later they die.

Thank you. It’s a really well kept van from what I’ve seen so far, very original.

[Aidan]

see my post in general - what did you do to your van today