Club 80-90 Forums

Broke down again last weekend, same symptoms, driving fine and just died on me.  Started but died immiediatly.

Fine 10 minutes later and for the subsequent drive home.

- New Fuel filter, Hall sender and loom connector arrived from BW, so i'll get them in as a starting point this weekend (along with cleaning up earths).
- Oil Pressure sender relocator and dual sender arrived so I can fit a VDO Gauge to monitor temps better.

- On the coolant front, I have shorted the Coolant gauge at the fusebox as per the wiki and no movement.  Is there any guidance on more detailed (/bench) testing of the coolant gauge floating around?

I've just installed the SLC Dash repair loom (no foil) so I doubt it's a wiring issue.  I did have the clocks apart a few times to rebuild the plastics so may have done something to the gauge itself?

at the risk of sounding like a stuck record but could it be TCi unit on way out (or suffering bad earth to body), symptoms fit

Aidan wrote: ↑01 Oct 2021, 17:23 at the risk of sounding like a stuck record but could it be TCi unit on way out (or suffering bad earth to body), symptoms fit

As above. And do a simple multi meter test on each of the loom pins connections to the ECU. It is the easiest way to dismiss 75% of DJ issues. I can send details if you do not have the procedure.
My ECU failed recently causing constant 12v at each injectors and bad flooding.
This simple test isolated the problem..and with the help from this forum too, of course.
I reset timing recently. Now running sweet.

Some progress, although in the spirit of one step forwards, one step back...

- Cleaned block earth strap connections,  strap is looking tatty and a bit frayed so have ordered a beefy replacement (and another to add to starter).  Feels like it starts better, although could be my imagination!

- Checked over dash connections and got the coolant gauge working again...however after runnign for 5-10 mins the temp creeped up to around the first white line, LED flashing.  However, the Fan had not kicked in, which seems odd.  Will check fuses and test fan at the switch connections tomorrow.  Not sure if it's a 'real' overheating reading or not.

- Connections to the two Blue Coolant Temp senders were the wrong way round (ECU was connected to side facing sensor, Gauge was connected to front facing).

- Ran most of the tests from the ECU loom plug from Bentley.  Coolant temp seemed to be odd, but turns out I was testing wrong sensors so will recheck. Mostly measurements were close to book spec.  Will retest coolant temp sender tomorrow.

- TCI ordered (Febi aftermarket, hopefully ok.).


 

ManicGTI wrote: ↑01 Oct 2021, 13:42 Broke down again last weekend, same symptoms, driving fine and just died on me.  Started but died immiediatly.

Fine 10 minutes later and for the subsequent drive home.

Just rereading through your posts...

Did it die at speed or at idle this time?

However, sort out your temp issues first. Without proper temp control other tests on a DJ are fairly pointless. The normal operating temperature range on the gauge is quite wide. But in general the temp needle sits around noon/1pm area.

First stage fan cuts in when needle hits about 2pm. Check switch in radiator by bridging pins with a piece of suitable size wire.

Flashing light is lack of coolant. Nothing to do with temperature.

Original plug to Temp II is moulded and not reversible. So there's one more for the list.

I would check timing. Check rotor for cleaniness and the coil lead for resistance.

Also consider removing the two Idle Stabiliser Unit leads and plugging them together. Run up to temp and set timing again. My DJ is running fine without one for three years and it solved a lot of mystery cutting out issues.

It died when moving, but at lowish speed (~1st/2nd gear, speedbumpy road).  

wrt the temp plugs, I meant the Junior Power Timer plugs were connected to the wrong sensors (rather than orientation of the plugs).    Blue ECU Temp plug was on the front facing screw in temp sender, Black JPT Plug (Dash gauge) was on the Blue 'Temp 2' sensor on side.  Swapped around now which I believe is how they should be.

Will check over dizzy/leads and redo timing when I rebuild the dizzy, but it's a bit of a moot point until I get temps sorted.  Dizzy and HT Leads are all only a few months old (by previous owner).

Whilst slightly painful it feels like this is a useful exercise to 'reset' the condition of everything to a known state.  Amazing how much can be slightly off on a van that on the face of it runs quite nicely!   Thank you so much for your input, I appreciate a lot of this is well trodden ground.

I'll check the fan and level sensor/loom at lunchtime...I had forgotten about that.  I thought the flashing light also operates on high temp (as well as level)?

No progress on the original issue but I'm glad I went through the process on the cooling system - on return to the van it turned out the temp gauge had stopped working at all (after I reinstalled dash) so when through the cooling systems electrics as a start.

- Rad fan fine - Both Rad Fan speeds work fine when shorting fan sender plug. I clearly heard 'fast' speed kicking in after it leaving van idling for a while.
- Have checked/confirmed relay, level sensor, temp sensor and looms.  Turned out to have an issue with connection between the SLC dash repair  wiring and the temp gauge itself.  Now rectified and gauge works as intended (flashes on start up then goes out, flashes on shorting of level plug, flashes and maxes out on shorting of temp sender plug).

I do have a cheap IR temp gauge, no idea on it's accuracy but it's fine for checking temp differences at least.  I'm not convinced stat is opening but was concentrating on getting the warning system working so will test again now.

In the process of messing around with the sender plugs I leant against the main coolant return hose and it started dripping (!), I had planned on replacing stat anyway so will inspect it all once the flange is off as I guess it could be the rubber hose or the plastic boss.  On my old Mk1 Golfs the plastic stat flanges used to warp/crack super easily so I assume same applies here.

As I'll be draining/flushing the system to change stat, it is worth changing the ECU and Gauge temp senders as a precaution at the same time or is that just a pointless exercise?

Ok, so an update!  Since last posting I have:

First stage (Fail - stopped on first journey out):
- Replaced TCI 
- Replaced Fuel filter (Didn't look old, but the fuel that came back out of it looked pretty brown)
- Replaced engine black earth strap and added additional strap to starter bolt.

Second stage (Fail - Idles fine, but now runs terribly when throttle opened from idle):
- Replaced Oil Filter, Oil.
- Replaced black and blue Temp senders (ECU and gauge), return hose, Thermostat cover and thermostat (80deG).
- Flushed and replaced coolant (G12 Pink)
- Installed Oil pressure sender relocator for oil pressure gauge (not yet connected)
- Rebuilt distributor with new BW hall sender, cleaned up loom and fitted new plug and cover.
- Temp install of cheap Voltage gauge and aftermarket rev counter.
- Set timing to ~5deg (currently has 95 in the tank, will adjust to 10deg when I refill with 98+).  Set timing with yellow connector unplugged, idle control box bypassed and vac hoses off the dizzy as recommended.

It now starts, and sits idling with coolant gauge showing stable, just on left hand edge of LED - which I gather is about right, maybe a tad cool.  I feel happy that the cooling system is behaving as it should, fan kicks in, temps all stable.  I'm aware it might be sensible to swap in an 87deg stat once I have it up reliable, but wanted to try and eliminate temp from the equation for the moment.

It feels like it idles a bit low when cool.  Once warm it idles fine, but runs really badly when throttle applied (undrivable).

Next up, check coil resistances I think.  Any further suggestions welcome.

Whip your engine ECU apart and get a good magnifier on the solder joint for the connector pins, and for the fuel pump and injector transistors (the two big ones at the end bolted to the aluminium casting)

I repair truck ECUs for a living and have been inside these DJ ECUs for various reasons over the years, and they always have dry and cracked solder joints on those transistors. Bad enough that I could well see them causing strange issues.

A friend of mine runs a 2 1 dj auto. Had issues with it cutting out. Turned out to be a blocked idle speed control valve. Are prone to blocking up.

Just a thought.

cobblers wrote: ↑09 Nov 2021, 17:37 Whip your engine ECU apart and get a good magnifier on the solder joint for the connector pins, and for the fuel pump and injector transistors (the two big ones at the end bolted to the aluminium casting)

I repair truck ECUs for a living and have been inside these DJ ECUs for various reasons over the years, and they always have dry and cracked solder joints on those transistors. Bad enough that I could well see them causing strange issues.

Thanks Cobblers,  I'll take a look.

I'll check the ISV (and also try bypassing), I believe from my Golf days they are cleanable.  I can't see this being the cause of my initial issue though.

I never thought i'd be pulling the ECU a few months into ownership - I fully expected i'd have to go through things checking/servicing but it feels like I have gone backwards!
 

If things are set up anywhere near right, the ICSV just adds "extra" air to lift the idle. Base idle of 800rpm is set up with the screw on the throttle body. Might be worth trying that actually, just unplug the electrical connector from the valve and see what happens. It shouldn't cut out unless its a very cold engine and there's a fair electrical load or something.

Just for completeness I thought I'd return and let people know where I've got to on this (for future searches!).  So maxstu, it look's like you were right...

maxstu wrote: ↑07 Oct 2021, 07:26

ManicGTI wrote: ↑01 Oct 2021, 13:42 .....

.....
Also consider removing the two Idle Stabiliser Unit leads and plugging them together. Run up to temp and set timing again. My DJ is running fine without one for three years and it solved a lot of mystery cutting out issues.

Since last message:
- Coil not replaced as I was sent the wrong part.
- New fuel tank, breather lines etc fitted.
- Timing reset to 10 deg from 5deg.After all this is was running and driving fine, albeit a little hunty at idle when cold.  So I decided to refit the idle control unit while I was working it out side the house.  Lo and behold after about 15-20 mins of idling it stalled and wouldn't restart - Same behaviour as before.

I immediately bypassed the unit and...it restarted and ran fine!  Swapped it in and out 4 or five times to check I wasn't going crazy and yup...ran fine without, and like a dog with it plugged in.  Bypassed it again and drove it to work yesterday in London traffic with no issues. Happy days!

So, Idle control unit seems to be the culprit for the main issue.  All the other issues I found along the way still needed sorting / rectifying, so it hasn't been a wasted process.

I've booked tunnel to France in a few weeks so wish me luck 

Hooray!

Goodluck and bon voyage!