4.2 SC LOTS of white smoke...

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ach2 said:
Not sure if I'm jumping in with no experience of Range Rovers, but I believe P0171 and P0174 could refer to the MAF - I had a pig of a job with similar symptoms on an old x-type with this. I found a thread here which may have some clues to help - and sorry for pointing to a different forum :)
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We welcome all to this forum and any information that may solve a problem. ;)
 
OK, update:
Put some injector cleaner in this morning. Started her up, as before it was like I was auditioning for the red arrows. As I drove through the village the houses on either side were completely obscured. Anyway, stopped about half a mile up the road with the engine running, took the oil cap off and slight change to engine note/revs but no great sucking vacuum. The smoke seemed to be clearing and I drove on, she changed over to LPG as normal and I then I stopped again, switched the LPG off and NO recurrence of the smoke. Went for a 30 mile drive, absolutely no problems, going great. So, contrary to what I previously thought, it does not seem to be a petrol related issue (unless the injector cleaner worked that quickly? Doubt it...) but a when cold thing. I am gong to let her cool down and then try starting again in a few hours.

The engine light came up again after about 15 miles, which was for the 171 and 174 codes (this came up when I was on LPG), BUT I now also have 172 and 175 codes pending - which is running too rich! Hmmm, MAF?

I did take the engine cover off before all this just to check I hadn't knocked a hose or something off when I did it last week, and all fine, BUT I did open the air box and the filter is like the inside of an old Dyson, so a new filter is needed methinks. Although as the smoke clears when she's warm I doubt if this is causing the smoking..??
 
Rawlplug said:
OK, update:
Put some injector cleaner in this morning. Started her up, as before it was like I was auditioning for the red arrows. As I drove through the village the houses on either side were completely obscured. Anyway, stopped about half a mile up the road with the engine running, took the oil cap off and slight change to engine note/revs but no great sucking vacuum. The smoke seemed to be clearing and I drove on, she changed over to LPG as normal and I then I stopped again, switched the LPG off and NO recurrence of the smoke. Went for a 30 mile drive, absolutely no problems, going great. So, contrary to what I previously thought, it does not seem to be a petrol related issue (unless the injector cleaner worked that quickly? Doubt it...) but a when cold thing. I am gong to let her cool down and then try starting again in a few hours.

The engine light came up again after about 15 miles, which was for the 171 and 174 codes (this came up when I was on LPG), BUT I now also have 172 and 175 codes pending - which is running too rich! Hmmm, MAF?

I did take the engine cover off before all this just to check I hadn't knocked a hose or something off when I did it last week, and all fine, BUT I did open the air box and the filter is like the inside of an old Dyson, so a new filter is needed methinks. Although as the smoke clears when she's warm I doubt if this is causing the smoking..??
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You sure nobody put diesel in it ?or playing silly buggers with you?
 
Pretty sure! Would it be possible to put diesel in it? The nozzle is larger on diesel pumps no?
Also, the smoke clears after a bit whether on LPG or petrol, presumable if it was diesel it wouldn't.
 
Rawlplug said:
Pretty sure! Would it be possible to put diesel in it? The nozzle is larger on diesel pumps no?
Also, the smoke clears after a bit whether on LPG or petrol, presumable if it was diesel it wouldn't.
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All engines will emit a certain amount of white smoke starting from cold. That is normal, should dissipate as engine warms. Over fuelling would be black. Oil would be blue. Water would be white. Diesel in petrol would be white.
 
I still think your lpg evap is leaking internally and allowing water into the system somehow.
I would turn it off and bypass the evap for now and see if that solves the issue.
I don't know a huge amount about lpg systems but they do use engine coolant to evaporate the lpg.
Wouldn't take much water to produce lots of smoke/steam and it would certainly screw up the mixture.
 
Wazzajnr said:
I still think your lpg evap is leaking internally and allowing water into the system somehow.
I would turn it off and bypass the evap for now and see if that solves the issue.
I don't know a huge amount about lpg systems but they do use engine coolant to evaporate the lpg.
Wouldn't take much water to produce lots of smoke/steam and it would certainly screw up the mixture.
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A definite maybe.
 
wammers said:
All engines will emit a certain amount of white smoke starting from cold. That is normal, should dissipate as engine warms. Over fuelling would be black. Oil would be blue. Water would be white. Diesel in petrol would be white.
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Sure, but not lay down a smokescreen (other than my Series 3 that is...). Smoke from diesel contamination would persist whether at startup or 30 miles down the road surely? I remember my dad put diesel in our Austin Maestro in about 1988 in France, there was no discernible effect other than having to switch the engine off by stalling it every time...

Wazzajnr said:
I still think your lpg evap is leaking internally and allowing water into the system somehow.
I would turn it off and bypass the evap for now and see if that solves the issue.
I don't know a huge amount about lpg systems but they do use engine coolant to evaporate the lpg.
Wouldn't take much water to produce lots of smoke/steam and it would certainly screw up the mixture.
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Coolant level is unchanged, and the smoking does stop after a few minutes.
 
Rawlplug said:
Sure, but not lay down a smokescreen (other than my Series 3 that is...). Smoke from diesel contamination would persist whether at startup or 30 miles down the road surely? I remember my dad put diesel in our Austin Maestro in about 1988 in France, there was no discernible effect other than having to switch the engine off by stalling it every time...



Coolant level is unchanged, and the smoking does stop after a few minutes.
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OK carry on you know best.
 
No not really. Just discussing, on a discussion forum!
Many thanks for all the responses to this problem, it really is much appreciated.
 
Don't know if yours has got one .But i did a vw crafter some months ago that fired out lots o white smoke when cold ,It was the egr heat exchange had failed didn't loose a lot of water and was fine when hot ,sound very similar;)
 
OK, update: Started the car again on Sunday - only a few seconds of smoke, then cleared. Drove 30-odd miles, all fine. Started her again about 5 hours later - no smoke! Started again this morning and again just now - no smoke! Interestingly, the engine light has also gone off (but 171 and 174 codes still current when plugging in the reader).
So, was it just a sticking injector all along and the cleaner has sorted it?? Why has the engine light gone off, but there are still current codes stored?
 
Rawlplug said:
OK, update: Started the car again on Sunday - only a few seconds of smoke, then cleared. Drove 30-odd miles, all fine. Started her again about 5 hours later - no smoke! Started again this morning and again just now - no smoke! Interestingly, the engine light has also gone off (but 171 and 174 codes still current when plugging in the reader).
So, was it just a sticking injector all along and the cleaner has sorted it?? Why has the engine light gone off, but there are still current codes stored?
Click to expand...

Well that's good news. maybe running it with oil cap off allowed oil to get where it shouldn't with no positive pressure. Its burnt off now.

However.. I'm still not happy about the too lean mixture reading on the o2 sensors. don't spank it around. It would be a pity to burn a valve or two.

Do you have live readings on your diagnostics? look at o2 sensor live data and rule out failing sensors. do you have leaks on the down pipe to cat joints ?

Also look at live data for the fuelling. let's get the PO171 / 174 codes sorted
 
The old saying goes Fat and Happy i'd rather run an engine rich than Lean any day of the week..

Ideally it should be a happy medium, more so on the AJV8..

Monitor everything..

Did you pull the plugs and have a look at them..

Plugs can tell a story as to how the motor is behaving, deposites, colour heck even the smell can be a good indicator to any issues.
 
Thanks both. I'll certainly take it easy until I'm sure it's sorted.
I don't think I have live date on my reader, it's the iCarsoft one. I'll have look. TBH though we're rapidly heading towards the limit of my technical competence!
Speaking of which, no, I didn't pull the plugs - I couldn't even find the ruddy things!

Would it be reasonable to run just on petrol for a bit, just to see if the codes re-emerge? That would at least rule out lamdas, leaks etc if so.
 
OK, used the car yesterday to/from work, 25-ish miles total with the LPG switched off, so running on petrol only: no codes, no pending codes, nada.
Could I confidently point to the LPG as the problem? - or does the car need to be run for longer?
 
OK, quick update in case any one else experiences the same: no return of the smoke. I put the injector cleaner in but I doubt this would have made a difference, so, I reckon leaving the oil filler cap off and driving 20-odd miles must have sucked some oil somewhere where it shouldn't go...
The running lean issue seems to be sorted too - turns out my LPG vapourizer was not up to the job (only rated at 280 bhp or thereabouts), so KME Twin now in, rated at 400bhp or so, and all seems good. Touch wood.
Many thanks for all the help and advice in this thread!
 
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