Injector Deviation (VCDS)

jonjo

jonjo

Member
Spotted some stinky whitish/grey smoke at idle the other day, I'm not usually out of the car when the engine is running.

Had also noticed some occasional shudder at idle in traffic and just thought it was characteristic cold poor running.

Popped it on VCDS to see what the injectors were up to and found Cylinder 3 maxing out.
Ran a log on my return commute today and made a graph (attached). Adjusted Coolant and Boost % for scale.

Can anyone tell me if this is compression, camshaft wear or injector failing? All hideous!
1 bottle of wynns Diesel Injector Cleaner is already in.
I was running Millers Eco Boost with every tank.
 

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I am not an expert, but it seems that you have a fault with injector three from looking at this graph.

Assuming you've been running the Millers additive over several thousand miles or more (at least 10 tanks) - if the cause was just a dirty injector it should have noticeably improved by now as it's good stuff.

Depending on whether you need to minimise the time the car is off the road, I would ideally pull all three and send them for reconditioning, else I would source a replacement injector just for No. 3.
 
Thanks all,

Planning to get this open at the weekend and check the loom (any tips/guides appreciated), then, if that's showing decent, remove suspect injector and visually inspect, perhaps switch it for another and see if the problem follows as @dj_efk suggests. Although sods law, I'll get one re-con'd and the others will fail a month later!

Does anyone know if we can rule out cam lobe wear or have any test method for that if I get the cam cover off? I've heard of probing it but I don't have the kit for that.
 
jonjo said:
Thanks all,

Planning to get this open at the weekend and check the loom (any tips/guides appreciated), then, if that's showing decent, remove suspect injector and visually inspect, perhaps switch it for another and see if the problem follows as @dj_efk suggests. Although sods law, I'll get one re-con'd and the others will fail a month later!

Does anyone know if we can rule out cam lobe wear or have any test method for that if I get the cam cover off? I've heard of probing it but I don't have the kit for that.
Click to expand...
Does this help, there are loads of similar vids.
Mac.
 
jonjo said:
Thanks all,

Planning to get this open at the weekend and check the loom (any tips/guides appreciated), then, if that's showing decent, remove suspect injector and visually inspect, perhaps switch it for another and see if the problem follows as @dj_efk suggests. Although sods law, I'll get one re-con'd and the others will fail a month later!

Does anyone know if we can rule out cam lobe wear or have any test method for that if I get the cam cover off? I've heard of probing it but I don't have the kit for that.
Click to expand...
I have replaced my injector harness twice. On both occasions the engine ran much better but I could find nothing wrong with the old harnesses. So you could check out the harness, decide it is good, have No 3 injector overhauled and find you still have a problem.
I have read that some members clean / adjust the terminals and that improves things. I would be tempted to check out, adjust, clean or replace the terminals on No 3 and see if you get an improvement.
Cam wear will be obvious once the cover is off. Follow the manual for removal and refitting the cover otherwise they leak oil badly.
If you go down the injector replacement route follow the manual fully, I've seen these engines on Facebook that have blown the cam cover to pieces.
 
jonjo said:
Thanks all,

Planning to get this open at the weekend and check the loom (any tips/guides appreciated), then, if that's showing decent, remove suspect injector and visually inspect, perhaps switch it for another and see if the problem follows as @dj_efk suggests. Although sods law, I'll get one re-con'd and the others will fail a month later!

Does anyone know if we can rule out cam lobe wear or have any test method for that if I get the cam cover off? I've heard of probing it but I don't have the kit for that.
Click to expand...
If you're taking it apart to that extent I would send the injectors off for a refurb - I got mine done at Darwen diesels and they were both quick and good value for money. Car ran like a sewing machine after they were refitted.
 
Definitely don't want to cam cover off too many times, there's a sequence of the bolts to loosen off and tighten to avoid warping. Then why not change the loom and get injectors refurbed, all done then in one hit, good for another 150k miles
 
Right-oh, you lot have motivated me to take a look early. I took care to undo in the correct sequence. Gave up trying to wiggle the top cambelt cover out!

Can anyone spot a worn cam lobe?

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I had a similar issue with idle deviations on my ATL. Camshaft looked ok 👌, but it is hard to spot a flat lobe in situ. Worse would be a hole or damaged lifter. What also could cause and explain compression issues. So there is only one way to find out and remove the camshaft. I changed mine, but it didn’t solve the issue. A compression test through the glow plug holes could give you answers and possibly rule out faulty compression on third cylinder. I didn’t.
Mine does still have deviations of +1 on the third injector which are compensated by injectors 1 and 2. But the car runs fine. Fuel consumption is still on par, 65mpg. So I don’t bother any longer. Reconditioning the injectors I find very expensive, at least here in Holland, but that will be my next step if the figures change. The middle photo shows the cam follower of the third cylinder and its wear.
 

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Hope this helps in your strategy to solve your issue. You got me wondering what would cause the white/ grey smoke? That would suggest the burn of water or vapor of any kind? Would it not?
 
DuncanA2 said:
Hope this helps in your strategy to solve your issue. You got me wondering what would cause the white/ grey smoke? That would suggest the burn of water or vapor of any kind? Would it not?
Click to expand...
Probably a small amount of 'neat' diesel leaking through the injector & blowing through the cylinder unburnt and smoking in the cat/exhaust was my thinking...
 
Thanks all, had a decent bash at it today, 12 point driver bits needed for the locking blocks and the rocker 🙄

Injectors were a bit manky and a bit of fuel leaked into the cylinder when they came out so I’ll have to crank it without plugs to clear them.

Loom came out fine, and recon injectors are in, measured for orientation and ready for calibration. Hopefully get my hands on a dial gauge to set the lash tomorrow.

Glow plug harness crapped out on me, the rubber boots at the end just stayed on the plug! Hoping those boots being integral to the whole loom is not essential for starting so I can crack on with the rest.
 

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It's annoying the glow plug lead situation isn't it, all mine are cracked or weak. I don't fancy splicing the loom on such an important wire.
 
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