T25 Fuel injection engine (water-cooled) keeps cutting out.
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T25 Fuel injection engine (water-cooled) keeps cutting out.
Hi
We have a T25 water-cooled engine fuel injection that keeps cutting out. It starts up ok but when you pull away and go into second gear it cuts outs and when you stop you can start up again. we feel this is a fuel problem but not sure how to diagnose this problem and are now at my wits end, any help please!!
We have changed so far fuel pump, filters, plugs, leads, distributor cap and ignition barrel.
We have a T25 water-cooled engine fuel injection that keeps cutting out. It starts up ok but when you pull away and go into second gear it cuts outs and when you stop you can start up again. we feel this is a fuel problem but not sure how to diagnose this problem and are now at my wits end, any help please!!
We have changed so far fuel pump, filters, plugs, leads, distributor cap and ignition barrel.
Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
I have a 2.1 ltr Digi-jet Waterboxer which developed this problem shortly after I acquired it some years ago. I went through the whole replacing parts process until almost all the ancillary parts were new. It would go for anything from 4 mile to 56 miles and stop. once it stopped it could be restarted after a while but would stop before it could be driven again. I got recovered twelve times mostly my my (nearly ex mate). After a recovery it required an overnight stand before it would go again. Three of times it had to be recovered from exactly the same place on the elevated roundabout on the Letchworth on the A1. On one the first of these recoveries I lay under the van to connect the solid tow bar and was severely shocked (electrically) as I came into contact with the metalwork. My mate - a pragmatic taught by wrote Hungarian motor mechanic - didn't believe me until he too was shocked. Being a multi-disciplined engineer educated to UOL standard I determined that the induced voltage from the low drooping overhead high tension cables over the roundabout was the cause of both the electric shocks and triggering of at least these three failure. Obviously a red herring.
It has to be said that when the failure occurred all necessary vital signs were present that is to say spark, injection pulse and fuel. Imagine my frustration.
So I did just what you have just done - got onto the forum.
Among the replies was one from Aiden of gearbox fame who suggested that as everything else had been replaced it might be worth looking at the ECU which is secreted under the floor on the left inside the engine compartment. He very kindly offered to loan me one to try. Sure enough it solved the problem and he ultimately sold it to me for a very fair price. I keep the old one stashed away in the van as It could get me out of trouble in an emergency.
This ECU being at the early stage of design, has many discrete components including electrolytic capacitors which are not known for their longevity. Fingers crossed for digijetteers then.
CS
It has to be said that when the failure occurred all necessary vital signs were present that is to say spark, injection pulse and fuel. Imagine my frustration.
So I did just what you have just done - got onto the forum.
Among the replies was one from Aiden of gearbox fame who suggested that as everything else had been replaced it might be worth looking at the ECU which is secreted under the floor on the left inside the engine compartment. He very kindly offered to loan me one to try. Sure enough it solved the problem and he ultimately sold it to me for a very fair price. I keep the old one stashed away in the van as It could get me out of trouble in an emergency.
This ECU being at the early stage of design, has many discrete components including electrolytic capacitors which are not known for their longevity. Fingers crossed for digijetteers then.

CS
Well-timed silence hath more eloquence than speech.
"A quiet shy boy who took little part in games or sport"
88 High top 2.1 WBX
"A quiet shy boy who took little part in games or sport"
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Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
temp2 sender maybe........but before you spend anymore money make sure you have clean and tight electrical contacts right across the engine bay, check the earths are grounding..........unplug clean repeat
mark
mark
1988 1.9 dg Caravel.
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Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
It could be the HT leads if you've got the ones with the metal sheath over the spark plug end. Remove those sheaths, which are only there to prevent interference with your AM radio signal, and see if the running improves. My van was running like a one legged dog because wayward sparks were arching out and earthing on the engine block.
Failing that, make sure all earths and electrical contacts are good, especially the negative strap from the battery, and volt test wires to make sure they've not corroded internally somewhere along the length.
Failing that, make sure all earths and electrical contacts are good, especially the negative strap from the battery, and volt test wires to make sure they've not corroded internally somewhere along the length.
1986 2.1DJ on carb. panel van/Reimo camper / 1991 2.1MV Swedish syncro doka
Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
chuckle-bus-tom wrote:It could be the HT leads if you've got the ones with the metal sheath over the spark plug end. Remove those sheaths, which are only there to prevent interference with your AM radio signal, and see if the running improves. My van was running like a one legged dog because wayward sparks were arching out and earthing on the engine block.
Failing that, make sure all earths and electrical contacts are good, especially the negative strap from the battery, and volt test wires to make sure they've not corroded internally somewhere along the length.
We have changed the leads but we haven't removed the metal sheath so will give that a try, thanks

Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
Citizen Smith wrote:I have a 2.1 ltr Digi-jet Waterboxer which developed this problem shortly after I acquired it some years ago. I went through the whole replacing parts process until almost all the ancillary parts were new. It would go for anything from 4 mile to 56 miles and stop. once it stopped it could be restarted after a while but would stop before it could be driven again. I got recovered twelve times mostly my my (nearly ex mate). After a recovery it required an overnight stand before it would go again. Three of times it had to be recovered from exactly the same place on the elevated roundabout on the Letchworth on the A1. On one the first of these recoveries I lay under the van to connect the solid tow bar and was severely shocked (electrically) as I came into contact with the metalwork. My mate - a pragmatic taught by wrote Hungarian motor mechanic - didn't believe me until he too was shocked. Being a multi-disciplined engineer educated to UOL standard I determined that the induced voltage from the low drooping overhead high tension cables over the roundabout was the cause of both the electric shocks and triggering of at least these three failure. Obviously a red herring.
It has to be said that when the failure occurred all necessary vital signs were present that is to say spark, injection pulse and fuel. Imagine my frustration.
So I did just what you have just done - got onto the forum.
Among the replies was one from Aiden of gearbox fame who suggested that as everything else had been replaced it might be worth looking at the ECU which is secreted under the floor on the left inside the engine compartment. He very kindly offered to loan me one to try. Sure enough it solved the problem and he ultimately sold it to me for a very fair price. I keep the old one stashed away in the van as It could get me out of trouble in an emergency.
This ECU being at the early stage of design, has many discrete components including electrolytic capacitors which are not known for their longevity. Fingers crossed for digijetteers then.![]()
CS
Thats what we thought it might be aswell!! got a couple of things to try but then this is going to have to be an serious option! thanks

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Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
Another thing I'd like to add is that I have a 2.1DJ in my camper running on a single carb and it's an absolute joy! All the torque and grunt of a 2.1 but the simplicity of a 1.9!
1986 2.1DJ on carb. panel van/Reimo camper / 1991 2.1MV Swedish syncro doka
Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
chuckle-bus-tom wrote:Another thing I'd like to add is that I have a 2.1DJ in my camper running on a single carb and it's an absolute joy! All the torque and grunt of a 2.1 but the simplicity of a 1.9!
I don't like to talk about the old girl like this but I do miss the foot down howl of my Bedford CF's. both the 1800 - so smooth and 2300cc which howled like it would explode nut never did! The low end torque and grunt of the injected 2100 DJ is fine but I do miss the odd nutcase foot down high rev burst you can get with a carb and no rev limiter. When I had the ECU problem I did think of fitting a carb . My gear changing is not helped by the near absence of engine noise of the rear engine on the T25. Better since I fitted a rev counter. Got to say I was never impressed by the engine where the bed should be on the split screen and bays and only got the T25 cos it turned up cheap when the last CF went all brown and soggy.
But the lower engine bay along with its many other features has grown the T25 on me over the years and it has joined my precious collection of man things never to be relinquished.

Cheers
CS
Well-timed silence hath more eloquence than speech.
"A quiet shy boy who took little part in games or sport"
88 High top 2.1 WBX
"A quiet shy boy who took little part in games or sport"
88 High top 2.1 WBX
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Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
Lorhob, Spookily on the day you posted this thread I had exactly the same problem, the only difference being that when mine is running the battery light comes on intermittently and stays on. Instead of creating a new thread, here's what I posted on the Facebook page, so could you please keep us updated, and if anyone has any further advice for me bearing in mind the subtle differences in the faults it would be really greatly appreciated.
"Advice required for a baffled T25 owner. I’ve got a 2.1DJ recon Vege engine with 6k on the clock. Yesterday took the old girl (and the van lol) for a spin, after a mile or so, lost all power, although the engine didn’t cut out just idled very slowly. After feathering the throttle for a couple of minutes power returned, drove away only for the same thing to happen again a few minutes later Power loss is such that the engine idled very very low, but did not cut out. Eventually I was able to drive home at 40-45mph with normal power although the battery light remained on constantly. Once home testing the battery and alternator showed 13.8 and 14.5volts respectively and the engine was running fine.
Today I started her, the engine turned over but idled very low as per yesterday, however today I could get no increase in power when feathering the throttle and today on the low idling revs the engine keeps backfiring. There is a strong spark from the coil to the distributor and also to the plugs. Having disconnected the return fuel pipe from the pressure regulator the fuel is clean and there seems to be sufficient pressure, although I haven’t been able to measure the pressure. I haven’t been able to check the timing yet, however the fact that yesterday it lost power, regained it, lost it regained it I don’t think it’s likely to be that. Hopefully I’ll will be changing the inline fuel filter tomorrow.
Another option is the Airflow meter, which is a 4 pin rheostat type, however I don’t know how to test this or what the relevant readings should be. Has anyone had experience of this fault and how it was remedied please, or can anyone give me any advice as to where to look next. Also, could anyone give me information as to which of the four pins on the Airflow meter are which in respect of live earth and resisted supply to ECU please and what the measurements should be bearing in mind the engine won’t run under power. Any advice/suggestions whatsoever would be very much appreciated. Thanks.
Further update; Haven’t as yet been able to undertake any of the suggestions from the Facebook page, however this morning, Sunday, van started first time and ran smoothly up to full revs, although the battery light was coming on intermittently and remaining on for several seconds at full revs, before going off again. Suggestions so far given include Vanagon Syndrome and Crown earths need cleaning." Thanks once again for any help which may be forthcoming.
"Advice required for a baffled T25 owner. I’ve got a 2.1DJ recon Vege engine with 6k on the clock. Yesterday took the old girl (and the van lol) for a spin, after a mile or so, lost all power, although the engine didn’t cut out just idled very slowly. After feathering the throttle for a couple of minutes power returned, drove away only for the same thing to happen again a few minutes later Power loss is such that the engine idled very very low, but did not cut out. Eventually I was able to drive home at 40-45mph with normal power although the battery light remained on constantly. Once home testing the battery and alternator showed 13.8 and 14.5volts respectively and the engine was running fine.
Today I started her, the engine turned over but idled very low as per yesterday, however today I could get no increase in power when feathering the throttle and today on the low idling revs the engine keeps backfiring. There is a strong spark from the coil to the distributor and also to the plugs. Having disconnected the return fuel pipe from the pressure regulator the fuel is clean and there seems to be sufficient pressure, although I haven’t been able to measure the pressure. I haven’t been able to check the timing yet, however the fact that yesterday it lost power, regained it, lost it regained it I don’t think it’s likely to be that. Hopefully I’ll will be changing the inline fuel filter tomorrow.
Another option is the Airflow meter, which is a 4 pin rheostat type, however I don’t know how to test this or what the relevant readings should be. Has anyone had experience of this fault and how it was remedied please, or can anyone give me any advice as to where to look next. Also, could anyone give me information as to which of the four pins on the Airflow meter are which in respect of live earth and resisted supply to ECU please and what the measurements should be bearing in mind the engine won’t run under power. Any advice/suggestions whatsoever would be very much appreciated. Thanks.
Further update; Haven’t as yet been able to undertake any of the suggestions from the Facebook page, however this morning, Sunday, van started first time and ran smoothly up to full revs, although the battery light was coming on intermittently and remaining on for several seconds at full revs, before going off again. Suggestions so far given include Vanagon Syndrome and Crown earths need cleaning." Thanks once again for any help which may be forthcoming.
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Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
Charlie1950 wrote:Lorhob, Spookily on the day you posted this thread I had exactly the same problem, the only difference being that when mine is running the battery light comes on intermittently and stays on. Instead of creating a new thread, here's what I posted on the Facebook page, so could you please keep us updated, and if anyone has any further advice for me bearing in mind the subtle differences in the faults it would be really greatly appreciated.
"Advice required for a baffled T25 owner. I’ve got a 2.1DJ recon Vege engine with 6k on the clock. Yesterday took the old girl (and the van lol) for a spin, after a mile or so, lost all power, although the engine didn’t cut out just idled very slowly. After feathering the throttle for a couple of minutes power returned, drove away only for the same thing to happen again a few minutes later Power loss is such that the engine idled very very low, but did not cut out. Eventually I was able to drive home at 40-45mph with normal power although the battery light remained on constantly. Once home testing the battery and alternator showed 13.8 and 14.5volts respectively and the engine was running fine.
Today I started her, the engine turned over but idled very low as per yesterday, however today I could get no increase in power when feathering the throttle and today on the low idling revs the engine keeps backfiring. There is a strong spark from the coil to the distributor and also to the plugs. Having disconnected the return fuel pipe from the pressure regulator the fuel is clean and there seems to be sufficient pressure, although I haven’t been able to measure the pressure. I haven’t been able to check the timing yet, however the fact that yesterday it lost power, regained it, lost it regained it I don’t think it’s likely to be that. Hopefully I’ll will be changing the inline fuel filter tomorrow.
Another option is the Airflow meter, which is a 4 pin rheostat type, however I don’t know how to test this or what the relevant readings should be. Has anyone had experience of this fault and how it was remedied please, or can anyone give me any advice as to where to look next. Also, could anyone give me information as to which of the four pins on the Airflow meter are which in respect of live earth and resisted supply to ECU please and what the measurements should be bearing in mind the engine won’t run under power. Any advice/suggestions whatsoever would be very much appreciated. Thanks.
Further update; Haven’t as yet been able to undertake any of the suggestions from the Facebook page, however this morning, Sunday, van started first time and ran smoothly up to full revs, although the battery light was coming on intermittently and remaining on for several seconds at full revs, before going off again. Suggestions so far given include Vanagon Syndrome and Crown earths need cleaning." Thanks once again for any help which may be forthcoming.
Possibly worn or sticking brushes in your Alternator? Do you get consistent readings off the alternator?
I've cracked open my Airflow meter and had a look. I even took some super fine wet n dry paper to the contact to smooth out any worn patches. Dicey stuff!
1986 2.1DJ on carb. panel van/Reimo camper / 1991 2.1MV Swedish syncro doka
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Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
chuckle-bus
Getting consistent readings from the alternator but will be replacing the brushes as soon as I can.
Because of the battery light I'm leaning towards an iffy earth somewhere, but also a little worried in case it's the Airflow (£306) but don't want to change it just on the off chance without exhausting everything else first. Sequence will be fuel filter, crown of thorns earth, alternator brushes......and not too sure what else before replacing the Airflow Meter/ECU.
Getting consistent readings from the alternator but will be replacing the brushes as soon as I can.
Because of the battery light I'm leaning towards an iffy earth somewhere, but also a little worried in case it's the Airflow (£306) but don't want to change it just on the off chance without exhausting everything else first. Sequence will be fuel filter, crown of thorns earth, alternator brushes......and not too sure what else before replacing the Airflow Meter/ECU.

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Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
It sounds more like you have a misfire. Is everything a little hot in there? Mine was like you described, judders and top speed of 40 at a push. If your HT leads have the metal sheaths then remove them first!
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Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
I have had the same problem in the past.
I have a 1990 2.1 petrol injected automatic and when I bought it 8 years ago it used to cut out completely randomly...but normally at the most inappropriate times, like a going round a roundabout!
I took it to 3 different garages, but no one knew what was wrong. The problem ended up costing about 60p...it was a plastic t-piece which had perished slightly and was causing petrol obstruction/leak.
Now, 8 years later its doing it again - I went into the garage 2 weeks back as it was cutting out again ( this time i could smell petrol)...it was a petrol leak again. Since then - no cutting out at all.
Hope you get it fixed x
I have a 1990 2.1 petrol injected automatic and when I bought it 8 years ago it used to cut out completely randomly...but normally at the most inappropriate times, like a going round a roundabout!
I took it to 3 different garages, but no one knew what was wrong. The problem ended up costing about 60p...it was a plastic t-piece which had perished slightly and was causing petrol obstruction/leak.
Now, 8 years later its doing it again - I went into the garage 2 weeks back as it was cutting out again ( this time i could smell petrol)...it was a petrol leak again. Since then - no cutting out at all.
Hope you get it fixed x
1990 2.1 petrol injected Caravelle
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Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
Intermittant cutting out , then running fine can be caused by air getting into the fuel line. It only needs a very small pinhole somewhere.
It happened to me the year before last when touring in Scotland. Fortunately I was able to book it into a local garage and he replaced the fuel lines - problem sorted!
It happened to me the year before last when touring in Scotland. Fortunately I was able to book it into a local garage and he replaced the fuel lines - problem sorted!
1990 Autosleeper Trident. Water cooled 1.9L DG + 4 speed manual box
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Re: T25 Fuel injection engine (water-cooled) keeps cutting out.
Like others have said check all connections and especially earths. There is a big cluster in the engine bay on the left that should all be given a shine and tighten. I recently had a similar problem which I pinpointed to my temperature sender in the airflow meter. A good cleanup and normal service has resumed!
1988 VW T25 Westfalia Club Joker, 2.1 iDJ