MOT failure - ECU

[Landmark]

Hi Folks,
Our 1.4 petrol Berlingo (Eng TU3JP KFX) has just failed its MOT on emissions. I have put other post on trying to cure the problem but to no avail.
It's had new air filter, MAF sensor. O2 & cat 2 yrs ago. The mechanic thinks it's the engine ECU as its running very rich and drinking petrol. He's suggested getting it checked at a Citroen specialist as he doesn't have the detailed equipment.
My question is how much is a new ECU likeley to cost? I've seen second hand ones on ebay etc, but not for our model.
Also could it be anything else?
In a panick now as we need the car daily and the MOT expires next week.
Thanks in advance,
Griff

[Lighty]

ECU failure is very unlikely, has he checked the coolant temp data , with engine running ? This would be the most obvious, could be the sensor itself, or maybe your thermostat is stuck, causing the engine to run cold.

[Gadgetman]

Which vintage Berlingo?
Which model ECU?

Spotted a Magneti Marelli that fits my older 1.4i engine for £125 + postage on eBay, announced as 'New with slight cosmetic defect'.
Used ones can go for as low as £25, but mostly seems to be at around $50 + postage. May need reprogramming for immobiliser, though.

But first I'd suspect one or more sensor to be faulty somehow.
(Those in the throttle housing or inlet manifold can be dirty and therefore be slightly off)

If cleaning sensors doesn't help, I'd start on the engine. Pull the plugs and see if any one looks different?
If not, check compression.
(Your engine should get 10.5 Bar pressure when warm)

Thermostat is easy to test. Bleed down the level of coolant so it's below the thermostat housing. Remove thermostat and visually check that it's closed.
If so, drop it in boiling water. It should open fully within a few seconds.
After fitting it(or a new one) you'll need to top up the system and bleed it, of course.

You may also have a problem with one or more injectors.

I've dealt with mrinjectoruk.com before, and they usually have all the parts you need. (reconditioned injectors, refurb kits and seals. Pretty awesome on email, too. That's my experience, at least.)
DO NOT pull the injectors without good reason though.
First off, it's a pain in the ... and second, you'll need new seals. The old ones will not be good.

[addo]

I fitted new O-rings to my injectors from a generic box of such. They were actually AC ones from memory. A little petroleum jelly helps slip them on and fit in the head.

My van has 400K on the motor with only one head gasket change (very recent). It starts on the button and is reasonably thrifty. So there's nothing inherently problematic with the injected 1.4 engine.

Gadgetman, I may have a factory unlocked ECU for you. Will check.

[Gadgetman]

Don't use Petroleum Jelly.
Use Dot4+ Brake fluid.
(At least that's what the guy behind the MrInjector site recommends for the correct seals)
The corect seals aren't all that expensive, either, on that site. Don't want to think about what Citroën charges...

But unless there's signs of leakage, or inspection of the plugs indicates that one is leaking into the cylinder, don't touch them. It's an effing pain in the seating area to remove and remount them.

Using Lexia3, it's possible to run an activation test on the injectors and a few other components. You can actually HEAR the injectors click open...
With a specialised stethoscope for engine testing you can listen to each injector in turn to verify that it sounds OK. (They're firing in pairs, so you can't really hear it directly)

Check for air leaks around the intake manifold. The brake system is powered by Vacuum from it(connects to the side of the pipe nearest the throttle body), and depending on which fuel pump you have and the number of fuel lines, there may be a tube from the intake manifold(other end, away from throttle body) down to a pressure regulator on the high-pressure reservoir over the injectors. There may be another tap for vacuum next to it, too, but can't remember what it is for.
(I have one or two of these regulators laying about, incidentally, possibly a complete reservoir for one, too.)
A leak at any of these places can cause the actual pressure and airflow to be different from what the sensors registers.


The 1.4i engine is a really nicely designed 4cyl, thing. It's very light because of the all-aluminium casting(with press-fitted steel sleeves), but still robust enough to take a lot of miles.
One mechanic I know of say that he wouldn't worry about wear on it before it passes 200K miles if it is being driven with a bit of care, even in work vans.
The ones used in Citroën AX and AX GTi races, probably won't last that long, though, and for the ones used in Rallying... All best are off...
Anyway, the ones in our beloved Berlingos is the result of a decade or two of refinement on the basic engine, and there are no real 'weak spots' on them any more.
The next step is the ET3 with variable timing valves, and then the Prince series built in co-operation with BMW. (Which kind of annoys some die-hard Beemer owners... And the fact that they even ended up in some Minis... Asking a mini owner how he enjoys driving his French car is really fun. After all, the Engine is the heart and soul of the car... )

I may be on the trail of a more local ECU.
Been calling around to friends and friends of friends.

[addo]

They have to come out when you service the head; I gave them and the fuel rail a redneck clean with the parts washer then carby clean to rinse out. I also replaced the intake manifold O-rings as they'd hardened with age.

Griff, you should do a compression check.

[Landmark]

Hi Guys,
Thanks for the replies. The thermostat is ok and a new MAF sensor was fitted yesterday, but did not solve the problem. I have had to book it into the Citroen garage to get it on the diagnostics as we need the car on a daily basis, so hopefully the technician will be able to pinpoint the problem.
Will update in due course,
Griff

[ron]

Good luck.:thumbsup::thumbsup:

[Landmark]

Hi Folks,
Got diagnostics done and showed up several codes. It appears to have been a combination of the following faults
1. NGK spark plugs fitted. Technician asked what plugs were fitted even before running test & said they do not like NGK plugs.
2. Third party coil fitted. It appears there is some "electrikery" in the manufacturers pack that has something to do with fuel metering.
3. The above has led to intermittent missfiring that had damaged the pre-cat O2 sensor.
4. Slight crack in the exhaust manifold that probably led to O2 sensor reading a weak mixture.
Anyway everything sorted and MOT passed.
A happy but poorer Griff

[brodfather11]

Glad your sorted out , and thanks for letting us know the cure.

alut: