2.1 DJ playing up when hot

[burnzdog]

Sorry if this a stupid question but I was expecting to find the ignition module on left ha d side of engine bay next to coil etc but it's nowhere to be seen. Is it possible it doesn't have one?

I would suspect the ignition module, tci, 191 915 351 B, failure when hot restarts when cold is pretty much the differential diagnostic for that - especially check the mounting screws are making good contact with the body metal and not just rusty as one of them is an earth, because they stick into the wheel arch they tend to rust

[Aidan]

does your distributor have a vacuum unit on the side of it ?
and where is your ECU ?

[Robsey]

I think it is time to break out the camera and get a few photos of all the obvious bits.

Distributor and vacuum unit.
ECU
TCi Unit.
Pretty much the whole area around the coil.

Probably worth looking for perished vacuum pipes as well.

[burnzdog]

[Aidan]

so it looks like ecu is behind the left side lights which is correct for a DJ
some DJs had the TCi unit mounted to the right of the black junction box but in your case I am wondering is it inside the junction box that cable on the top with the green wire looks wrong to me follow the thick green or green and white wire...............

[burnzdog]

Thanks Aidan.

No it's not in the junction box, I will have a better look when I can get out there later but from a quick glance I can't see anything. That cable you mention is lose and has never been plugged in.

so it looks like ecu is behind the left side lights which is correct for a DJ
some DJs had the TCi unit mounted to the right of the black junction box but in your case I am wondering is it inside the junction box that cable on the top with the green wire looks wrong to me follow the thick green or green and white wire...............

---

[Aidan]

post up a pic of the disi
and take a look at the plate under the left side seat for the type number, 6 digits/letters starting 25
'cos the more I see the more I think that is/was a MV - just because it has DJ stamped on the block doesn't mean that its running Digijet ignition/fi

[burnzdog]

Dizzy pic



Code is 253G C7

Defo a DJ block. But It does look like it's been altered in the past due to the various cables in the loom doing nothing. I have been using it perfectly fine for last 7 years so this has been the setup since I've owned it.

[Aidan]

253 GC3 is a LHD Kombi with either an MV or SS engine, so Digifant originally, ECU should be in the van under the rear seat though some odd vehicles had them behind the rear lights. Check the part number on the ECU to confirm its the correct one, wiring is different between Digifant and Digijet (DJ engine) so if its got a Digijet ecu then the wiring will have been messed with, but I'm fairly confident you'll find it is a Digifant ECU, part number 025 997 022 or 025 906 022 D
Your wiring loom and ignition system is Digifant, so safe to say the engine has been swapped, but it is still running Digifant. There is no vacuum unit on the side of the distributor I think, and the plug for the hall sender is square form rather than oval.
The cable tucked over the top of the junction box is the lambda sensor wiring, MV/SS had a cat and lambda sensor in the exhaust, DJ dosesn't have that so engine hasn't been running optimally, a bit more fuel inefficient that necessary because it has no lambda fitted.
The Digifant ECU controls timing and fuelling, the TCi unit is built into the ECU as is the dls unit.
I would suggest downloading the correct engine manual for the engine from Syncrosport website and then checking through the engine thoroughly, making sure you have the correct spark plugs WR7CC, or champion N-288, DJ has different spark plugs, checking the resistances of the coil and the spark plug leads and king lead are in spec, checking condition of cap and rotor arm and replacing if necessary - the coil isn't the original one, for example, can't see exactly what it is but quite corroded externally. The manual has all the diagnostics (like testing the hall sender from the disi, resistances of the components etc.. ) you will need, armed with a simple multimeter to figure out what is wrong
I'm guessing here but coil and ECU are points of focus for me with the symptom described
but equally could be rotor arm and or disi cap, they are different between DJ and MV so if you have been servicing the vehicle I would have thought you would have realised that it wasn't a DJ previously, cap and rotor are 2 year service items like the air filter, so if its not been serviced then its likely something simple.

[burnzdog]

Thank you I will focus on what you described. I do have a question tho, what differentiates a DJ from a Mv or SS? The physical engine is the same it's just the ignition, ecu and injector system around it?

253 GC3 is a LHD Kombi with either an MV or SS engine, so Digifant originally, ECU should be in the van under the rear seat though some odd vehicles had them behind the rear lights. Check the part number on the ECU to confirm its the correct one, wiring is different between Digifant and Digijet (DJ engine) so if its got a Digijet ecu then the wiring will have been messed with, but I'm fairly confident you'll find it is a Digifant ECU, part number 025 997 022 or 025 906 022 D
Your wiring loom and ignition system is Digifant, so safe to say the engine has been swapped, but it is still running Digifant. There is no vacuum unit on the side of the distributor I think, and the plug for the hall sender is square form rather than oval.
The cable tucked over the top of the junction box is the lambda sensor wiring, MV/SS had a cat and lambda sensor in the exhaust, DJ dosesn't have that so engine hasn't been running optimally, a bit more fuel inefficient that necessary because it has no lambda fitted.
The Digifant ECU controls timing and fuelling, the TCi unit is built into the ECU as is the dls unit.
I would suggest downloading the correct engine manual for the engine from Syncrosport website and then checking through the engine thoroughly, making sure you have the correct spark plugs WR7CC, or champion N-288, DJ has different spark plugs, checking the resistances of the coil and the spark plug leads and king lead are in spec, checking condition of cap and rotor arm and replacing if necessary - the coil isn't the original one, for example, can't see exactly what it is but quite corroded externally. The manual has all the diagnostics (like testing the hall sender from the disi, resistances of the components etc.. ) you will need, armed with a simple multimeter to figure out what is wrong
I'm guessing here but coil and ECU are points of focus for me with the symptom described
but equally could be rotor arm and or disi cap, they are different between DJ and MV so if you have been servicing the vehicle I would have thought you would have realised that it wasn't a DJ previously, cap and rotor are 2 year service items like the air filter, so if its not been serviced then its likely something simple.

[Aidan]

DJ is higher compression 2.1, originally designed for 4 star fuel, running a map based ignition system with only 4 input signals, air mass, air temp, water temp, timing from hall sender, using vacuum advance and retard for almost all the timing adjustment, ecu controls fuelling - nominally 112bhp on 4star when new

MV/SS engine is lower compression 2.1 designed for cleaner emissions, running unleaded fuel, with additional lambda sensor on exhaust so it can adjust the map based on sniffing the exhaust so as well as the fuelling the ecu controls the timing variation in order to get cleaner more efficient fuel burn and can also run on lower grade fuel, all the way down to 91 RON (like 3 star fuel) without adjustment and has catalytic converter fitted to additionally help with emissions. Primarily for the US market and some EU markets like Switzerland and Austria but increasingly sold in Europe towards the end of manufacture of the T3, nominally 95bhp on unleaded fuel

using a DJ engine on Digifant you won't get any benefit without lambda as ECU will just run stock slightly rich map for fuelling as it doesn't know the outcome, with a lambda it can adjust fuelling and timing to get optimum result, so you won't be getting 112bhp and you probably aren't getting 95 either

The different spark plugs put the spark in slightly different physical location in the cylinder for optimum burn so actually having DJ spec plugs might be optimal, you'd need to experiment to see if there was any noticeable mpg benefit. or any excessive erosion of the plug tips - these days getting the subtle variants isn't that easy but I found new old stock last year of the Champions on Ebay for sensible money, but the DJ Bosch version seem to be long gone and Bosch only offer a simplified range now, 1 plug fits all sort of thing

[burnzdog]

Yep it's a digifant as you thought. So I have a DJ engine with a digifant. All service items I purchased in the past were based on having a DJ engine, plugs, leads etc. The coil is the same I've never changed it, labelled bremi 11822.

I know that this is a DJ engine as it has the higher compression on cylinder as I have the results somewhere. What I'm trying to understand is why someone would have done that? Having the ignition system of a MV/Ss but a different engine. What would the benefit be?

Which makes me then think should I be using spark plugs/coil for a Mv engine or a DJ?

I mentioned I've not had an issue up until now. I will have to download the manual as you describe and start working thriugh the various tests as and when I get time.

You mention look at ECU and and Ignition coil as a place to start. Do you mean replacing these or checking earth and resistance?

Thanks for all your help this fa I really appreciate it

[Aidan]

I'd start with checking you have good earths, to the shell and to the engine, then the service items, rotor arm, disi cap, spark plugs, even just visual check can be diagnostic, is the sprung centre contact good, are the four plug contacts intact, rotor arm tip not excessively eroded etc.. for example if one plug is a different colour or wet /oiled or gaps are too big/too small; I'd look at what is fitted, what numbers, what brand, how old, how rusty, any cracks in leads, then I'd check the resistance of the spark plug leads and the lead from the coil, then I'd check the resistance of the coil halves are all within spec, if any is out of spec then possibly likely to break down when hot, also check plug shrouds are good and you aren't getting spark leakage; I'd check the signals to the ECU if I hadn't found something awry yet, ultimately if everything else is good and all the measurements to the ECU are correct then by elimination it must be the ECU which is full of 30+ old electronic components which are subject to degradation and some of which, like capacitors, often at end of useful working life. This stuff was well made at the time, with generally high quality components but tens/hundreds of thousands of use cycles take a toll ultimately, and corrosion is an issue generally on old vehicles, especially with the wetter weather we've had at times in recent years. My SA van didn't appreciate moving to the UK last year and suffering the damp of the end of autumn and the beginning of winter, that triggered the electrical gremlins.

[Aidan]

Bremi is a cheap coil, like £20 new, original Bosch was £150+, there will be a reason why its so cheap, and the fact it is rusty but not that old is suspicious, so that would be my first thing to check
Original Bosch coil is nla, they don't make them like that any more, there are alternatives and good used ones can be found and there are other choices of new stuff, even a new bremi might be great if that is the problem

Fitting a used DJ engine was a cheap easy solution to the problem previous owner was facing at the time, rebuild engine properly or get an excahnge for many thousands, or fit an available used one for £500....and then sell the van so its someone else's problem, it's what people do, pay £150 for a new genuine coil or fit a pattern one for £20 ?

[burnzdog]

Changed the distributor and seems to have solved the issue as far as I can tell. I would like to keep the original distributor so I think this needs hall sender changing. Has anyone got recommendation for this part as I can see quite a difference in price from various outlets. Thanks.

Bremi is a cheap coil, like £20 new, original Bosch was £150+, there will be a reason why its so cheap, and the fact it is rusty but not that old is suspicious, so that would be my first thing to check
Original Bosch coil is nla, they don't make them like that any more, there are alternatives and good used ones can be found and there are other choices of new stuff, even a new bremi might be great if that is the problem

Fitting a used DJ engine was a cheap easy solution to the problem previous owner was facing at the time, rebuild engine properly or get an excahnge for many thousands, or fit an available used one for £500....and then sell the van so its someone else's problem, it's what people do, pay £150 for a new genuine coil or fit a pattern one for £20 ?