406oc.co.uk

Could anybody help me shed some light on these injector correction values please, number one and number three injector values are way lower than two and four. Thanks.

I forgot to say these values were measured at idle!

First picture is of values at idle and the second picture is of values at 2000 RPM.

They don't look great, have you tried a leak-off test?

I've see worse

Those look higher than normal to me, nothing that either a good run or some injector cleaner won't address.

Ideally the values should be between 1.5 and 2.5 for a good clean injector - over 4 isn't problematic but shows it could be addressed

When I get my car back ( I've lent it to my nephew) I'll stick PP2K on it and compare injector values.

Doggy wrote: ↑Sat Oct 29, 2022 3:00 pm They don't look great, have you tried a leak-off test?

Yep looking around on youtube and several forums suggested things were not quite right, I haven't got a leak off tester but will get one ordered up today. Am I right in thinking the more that leaks off the more the injector is blocked?

I'm going to run some some BG245 injector cleaner through in the meantime and will check values again before the leak off kit arrives. Thanks for your advice, it's always best to check with you guys first as the knowledge here is immense

GingerMagic wrote: ↑Sat Oct 29, 2022 3:03 pm I've see worse

Those look higher than normal to me, nothing that either a good run or some injector cleaner won't address.

Ideally the values should be between 1.5 and 2.5 for a good clean injector - over 4 isn't problematic but shows it could be addressed

When I get my car back ( I've lent it to my nephew) I'll stick PP2K on it and compare injector values.

Thanks, I'm going to run a can of BG245 through it in that case and re-check the values as that does its stuff. Will order up a leak of test kit as Doggy suggested.
That would be great to compare the values of yours to mine, I really appreciate that, thanks

Regards,

Paul

Today I covered around 65 miles with the injector cleaner in the tank, being an auto I kept it in the low gears and worked the engine quite hard hoping it would blast some of the crud out.
I have just checked the correction values again and injector 2 and 3 are now sitting nicely at 1.45 mm3 and 1.61 mm3 whilst injector 1 and 4 are still really high at 4.12 mm3 and 4.96 mm3.

Checking the injector voltage I noticed I noticed on injectors 1 and 4 the voltage varied/shifted between 79.37 and 80.24 whilst injectors 2 and 3 stayed at a constant 69.88

There seems to be a whining noise coming from injector 4 and wondered if the copper seal washer between the injector and cylinder head has gone AWOL

The varying voltages and high correction values on injector 1 and four suggest to me they are faulty. Any pointers gratefully received on this

Thanks, Paul

Today I managed to do the leak off test, number 1 injector was the odd man out and leaked off far more than 2,3 or 4. With the voltage fluctuation on number 1 and 4 and the high amount of fuel leak off on number 1 I'm guessing the over fuelling problem lies here.

I'm going to swap these two injectors out for two that are known to be good and see what we get then

Sounds like you're on the right track.
When I had this problem, I had uneven idling and poor fuel consumption. Changing the worst injector made an immediate and obvious difference.
Bear in mind injectors come in 3 'classes' and ideally your ecu should be set to match those you have (or have most of).

Agreed, there is also a number printed on the injector ( 1,2,3 or 4 I think ) if the 2.0 is the same as the 2.2....

When I pulled number 1 injector it was blocked and dry as a bone, am I right in thinking this is paired with injector number 4 as that was really wet as though it had been over fuelling to compensate for number 1?

I don't have PP2000 so probably won't be able to code the new injectors in although I would say the cars performance was much improved after swapping out injectors 1 and 4 for some re-con ones and the flow correction readings were much better than they were, the excessive smoke at the exhaust has disappeared also the smell of unburnt diesel has gone. The whining noise at injector 4 is either gone or very quiet (I've only got one good ear though )

I'll give it a good 60 or 70 mile run tomorrow and see what happens.

These are the two injectors I've pulled, they were replaced with the same type and I am unsure where the value would be stamped/marked.

They are different to the ones fitted to a 2.2, (2.2 = Bosch 0445110036; 2.0 = Bosch 0445110076).

The set I removed in 2011 were 'class' 2, replacements were 'class' 3 but it's so long ago I can't remember where this was marked on them.
It ran OK before changing the ecu setting to match, but since I could update I did. Not sure if there was a real improvement as a result, so it's probably not a major issue if you don't.

Glad to hear it's solved your problem, well done.

The earlier injectors had 1, 2 or 3 on them. Later? ones like yours had x, y or z I think. Looking at the pic yours are Y.

I have a 406 that had bad starting/idling/lumpy acceleration/cruising. Checked it out with PP2000 and found the injectors were not classed (cant remember the exact phrase PP2000 gave). I reclassed them to the marking number and idle/running improved noticeably.