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Blue smoke from tail pipe + excessive positive pressure at oil cap + electronic fault light + dash warning light

  Clio III - 1.5dci
I defer to the wisdom of the forums. Just about ready to blow my brains out.

So, I recently got my hands on a Renault Clio III 1.5dci 68 - my friend overfilled the oil by half a litre and all hell broke loose. He got in a mood with it and sold it to me.

Initial symptoms:
* P0670/$07E8 - Glow Plug Control Module Control Circuit/Open (code pulled on a Foxwell OBDII scanner)
* Blue/White smoke out of tailpipe (smells like oil burning)

Initial repairs:
* Test all glow plugs (resistance was CRAP on all 4 of them)
* Replaced all 4 glow plugs
* Complete oil change with 5w40 magnetic, as he was using Halfords brand :sick: and I thought it worth a shot.

All codes disappeared at this point, well, none could be picked up by my eBay £12 OBDII scanner ? - HOWEVER, the following issues occurred and/or remained:
* Electronic fault warning light on (through ignition, turnover, and driving)
* Dashboard warning light on (the service spanner - through ignition, turnover, and driving)
* Blue tint smoke remains a constant issue and is particularly bad under load but still there when idling
* Difficult to start and rough idle until it warms up a little (1-2mins at most) then idle levels out (this was an issue from the start)
* Once warm, foot on accelerator to 1500/2000rpm seems to 'bounce' around when held steady, but 2000rmp+ no bouncing up and down ?‍♂
* OH! Also, at this point, I found a massive amount of positive pressure (I think it's called 'blowby?') coming from the oil filler cap.

I then tried the following to no avail:
* Clean MAF sensor with MAF cleaner spray
* Remove EGR valve and pipe and decarbonate (they both look brand new, GO OVEN CLEANER ??:cool:)

But, neither of these things fixed it.

I have noticed that there appear to be two or three spots under the very front portion of the car where oil is slowly leaking on to the road, and I mean slowwwwly... Absolutely no idea where that is coming from... I have taken a look at the cylinder head and am sure it's not a head gasket issue. Also, the coolant looks clear...ish? (It's due a change). I'm starting to think piston rings? The weird thing is that the car was running perfectly until he overfilled the oil!? Can anyone think of any other simple issues it could be before I give in and go and get a leak down test done?

Much love to the community ?,
I reckon a compression / leakdown test would be a good start, and should not cost much if you need to get it done at a garage.

Are there sensors in the exhaust that could be coated in a load of oil that got dragged through and thrown out the back after he overfilledit, and therefore might not be reading correctly?
  Clio III - 1.5dci
Yes, I believe there are two. One before the cat and one on or just before the manifold. I hadn't thought to remove and clean them. I will give it a go, for sure, however, I'm not getting any error codes relating to running lean or rich. Actually, I'm not getting any error codes at all, just the dash lights I mentioned!? ?
Good luck, I hope it is an easy fix! :)

You could perhaps try one of those 'cataclean' or 'terraclean' or 'redex' sort of cleaners, which you add to the fuel - perhaps it might help clear off any residue that is in the system / exhaust??
  Clio III - 1.5dci
Good luck, I hope it is an easy fix! :)

You could perhaps try one of those 'cataclean' or 'terraclean' or 'redex' sort of cleaners, which you add to the fuel - perhaps it might help clear off any residue that is in the system / exhaust??
I've got some Seafoam, so I'm tempted to run that through it. Thanks bud, fingers crossed. Worst case scenario I'll have to support the engine and break it down, i guess ?‍♂


ClioSport Club Member
  Kangoo 172cup
Needs Renault clip on to find out what codes are stored, generic obd scanner wont pick up much.

Blue smoke under load will be either knackered turbo or rings, or knackered injectors. Id comp test/leakdown testif you have access to one to suit a diesel, also take exhaust off at the turbo and see if any oil on the exhaust wheel on the turbo, as that will give you and indication if the turbo is shot.

Have you cleaned the egr out, that may help with poor starting, although it could be fuel pressure related, which will need live data to see whats going on when cranking.

Oil leak at the front of the engine will most likely be o rings leaking on the oil filter housing, they start leaking if disturbed when removing a tight oil filter. Nipping up the banjo bolt does not cure it if its leaking just bang some new o rings in.