Aftermarket ECU for 2.1 DJ

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shalfy1
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Aftermarket ECU for 2.1 DJ

Post by shalfy1 »

Hi
My first post to this forum, as I cannot find any information on fitting an aftermarket ECU to the 2.1 DJ engine.
It's something my engine tuner (a fuel injection specialist garage) mentioned, because they are at a loss as to figure out why the engine is struggling at mid-revs and running lean. Clean spark traces, good fuel pressure, injectors have been serviced, timing set, advance/retard checked, AFM checked and adjusted.
I would prefer not to modify the vehicle (i.e. fit an aftermarket ECU), but I'm running out of things to try.
Engine is good - a recent rebuild so the compressions are 10-11 bar. All hoses and manifolds have been checked.
Has anyone had any experience of having an aftermarket ECU fitted? If so, was there an improvement in engine drivability and/or fuel economy?
Thanks in advance.
Steve
1991 Autohomes Kamper 2.1DJ 5 speed

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R0B
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Re: Aftermarket ECU for 2.1 DJ

Post by R0B »

Is your van an auto or manual? I have a couple of auto ones here. This fella is a breaker he should have some S/h ones. https://forum.club8090.co.uk/viewtopic. ... 7&t=170191" onclick="window.open(this.href);return false;
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maxstu
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Re: Aftermarket ECU for 2.1 DJ

Post by maxstu »

Have they tested the current ECU? All in Bentley manual.
I would secure or borrow another DJ ECU to see if issue continues. I may have a spare one in a few weeks if you can wait?
Otherwise dump the lot and go carb instead.
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Aidan
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Re: Aftermarket ECU for 2.1 DJ

Post by Aidan »

possibly not an ECU issue, leaky brake vacuum hose from manifold would be my guess, they rust from the inside because they are steel reinforced, produces pin prick holes and so runs lean - DJs don't like air leaks on the intake side but leaky exhaust not much issue, MVs cope better with leaks on inlet side but leaky exhausts fool the Lambda so they run rich because they think they are running lean

spray some carb cleaner on the vacuum pipe and see if the revs increase to diagnose, brickwerks sell correct hose, cheap fix if I am right, and Neil busmonkeys will back me up on this he had exactly the same issue

shalfy1
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Re: Aftermarket ECU for 2.1 DJ

Post by shalfy1 »

Thanks Aidan.
A few months back a pin prick hole was found in the #3 manifold. It was sealed and made a surprisingly big difference to the emissions. I've recently removed both manifolds to visually check and they seemed OK but I will try your suggestion of spraying carb cleaner.
The garage that refitted the engine after its rebuild did an awful job. Gave it back to me with the air intake elbow hanging off the AFM, #3 exhaust manifold loose, exhaust pipe joint blowing, return fuel pipe from the regulator loose. These are the faults that I spotted - it beggars belief!
Next steps will be :-
Carb Cleaner suggestion from Aidan
Renew earth terminal and strap in engine bay
Check test readings on ECU connector as per manual
Any other suggestions are very welcome.
1991 Autohomes Kamper 2.1DJ 5 speed

shalfy1
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Re: Aftermarket ECU for 2.1 DJ

Post by shalfy1 »

OK - an update.

Spraying carb cleaner around made no difference to engine note.
Cleaned up earth terminals on LHS engine block and replace earth strap (block to engine bay). No difference.
Checked out electrical readings on ECU connector as per manual - all OK.
Check fuel delivery as per manual - hose to fuel regulator return into a measuring jug for 30 seconds. Fuel delivery within spec.

Just for good measure I removed the air filter housing from the AFM and whilst the engine was at idle I covered the air intake to the AFM. Engine stalled (as expected) and a good amount of vacuum was produced in the air intake knuckle causing it to collapse and slowly recover - not a recommended test, obviously, but all I could come up with in the absence of a vacuum tester.
I'd like to check the fuel regulator out but don't have a pressure gauge. I might have to put it in to the local fuel injection specialist (again).
Any suggestions are welcome.
1991 Autohomes Kamper 2.1DJ 5 speed

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maxstu
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Re: Aftermarket ECU for 2.1 DJ

Post by maxstu »

Check temp ll sensor and wiring connector to pipe from oil breather tower.
Idle sensor is vibrating right?
MaxStu
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Re: Aftermarket ECU for 2.1 DJ

Post by shalfy1 »

Thanks Maxstu.
Yes, idle speed valve vibrates. Which is Temp II?
I've done a resistance and voltage check on the breather pipe heater and it seems in order.
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maxstu
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Re: Aftermarket ECU for 2.1 DJ

Post by maxstu »

shalfy1 wrote:Thanks Maxstu.
Yes, idle speed valve vibrates. Which is Temp II?
I've done a resistance and voltage check on the breather pipe heater and it seems in order.

Off the top of my head temp ll is on ths side of the thermostat housing. But cant recall what part it plays. Give me five mins ....will dig out manual
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1989 DJ 2.1 Auto Leisuredrive rusty bucket.
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maxstu
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Re: Aftermarket ECU for 2.1 DJ

Post by maxstu »

It goes to ECU terminals 2 & 7.
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1989 DJ 2.1 Auto Leisuredrive rusty bucket.
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Re: Aftermarket ECU for 2.1 DJ

Post by maxstu »

I added gasket blue Holymar to all pipes to prevent air leaks


Can you access this file?


https://www.dropbox.com/s/t8ytvl6nry3t3 ... 9.pdf?dl=0" onclick="window.open(this.href);return false;
MaxStu
1989 DJ 2.1 Auto Leisuredrive rusty bucket.
"Blissfully happy in your presence".

shalfy1
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Re: Aftermarket ECU for 2.1 DJ

Post by shalfy1 »

Thanks Maxstu
Yes, got the file. I'll check it out on my laptop tomorrow. It'll be easier to read.
Yes, I checked the coolant sensor and it was OK.
1991 Autohomes Kamper 2.1DJ 5 speed

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Aidan
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Re: Aftermarket ECU for 2.1 DJ

Post by Aidan »

is there vacuum from the plenum chamber on the little spigot that feeds the reverse side of the vacuum advance on the disi and the fuel pressure regulator ? it works the opposite to the vacuum take off on the throttle body so more vacuum at idle and drops as the revs increase, so fuel pressure is lower at low revs as bypass valve is open and fuel can return to tank more easily and closes up a bit at higher revs so fuel lines are at full pressure so max fuel delivery every time the injectors open

shalfy1
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Re: Aftermarket ECU for 2.1 DJ

Post by shalfy1 »

Hi Aiden
Sorry for the tardy reply. I have been away for a few days.
I'll check out vacuum from the plenum chamber when it stops raining.
In the meantime, does anyone know which is the Brake Vacuum Hose? Maxstu referred to it earlier but I cannot find any mention of it in the manuals.
Where does it connect between?
1991 Autohomes Kamper 2.1DJ 5 speed

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Re: Aftermarket ECU for 2.1 DJ

Post by Aidan »

brake vacuum hose is the big one coming out of the left side of the plenum chamber by the small hose that goes to the distributor and pressure relief valve, it has a yellow and black one way valve at the end of the braided rubber hose and is solid plastic after that

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