Advertise on fullfatrr.com »

Home > Technical (L322) > 2007 Supercharged Misfiring
Post Reply  Down to end
Page 1 of 4 1234>
Print this entire topic · 
dhallworth



Member Since: 10 Oct 2011
Location: Glasgow
Posts: 3067

United Kingdom 2012 Range Rover Autobiography TDV8 Baltic Blue
2007 Supercharged Misfiring

My car has been a bit lumpy when cold since I’ve had it. Normally, once starting it and having left the driveway it’s a while before it returns to idle as we drive down the lanes, into the local village and a few mins later onto the dual carriageway.

This evening I jumped in the car and noticed I hadn’t locked the workshop so left it idling and by the time I got back in it the lumpiness had caused there to be a nice orange glow on the dashboard from the engine management light.

When reading the codes with the IID tool I saw this:

Click image to enlarge


I then had a look at the real time misfires and saw this:

Click image to enlarge


Interestingly, when the car is under load, the misfire counters read zero, when on overrun down a hill there were a few appear but the numbers above were mostly at idle in Drive.

The car had all 8 plugs and 8 coils replaced when I got it 12 months ago and they’ve only done around 3k miles. I replaced the PCV valve and pipe work too. As it was a bit lumpy back then I smoke tested the inlet myself and found nothing and also had a specialist do it with a high pressure smoke machine and he didn’t find anything either.

I’m wondering if it could be the MAF sensor causing it. Rather then just throwing parts at it I’d rather know it was wrong so does anybody know the readings that you’d expect under no load from the MAF?

Once the car is properly warmed up it’s smooth as silk and doesn’t register any misfires under load, overrun or at idle, it’s purely when cold. It also doesn’t feel down on power when it’s warmed up either.

Any help would be appreciated as I’m not sure where to look at the moment. Thumbs Up

Thanks,
David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2007 Range Rover Supercharged in Java Black with Ivory Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Post #622646 5th Feb 2022 10:29pm
View user's profile Send private message View poster's gallery Reply with quote
Bean19844



Member Since: 25 Oct 2020
Location: Essex
Posts: 929

United Kingdom 2006 Range Rover Supercharged 4.2 SC V8 Bonatti Grey

Could possibly be the petrol your using mate I guess. I've noticed that with mine. When I've used the regular e10 petrol either on the bike or in the range, in the cold they seem to start up slightly lumpy but after a short while it seems too sort itself out but soon as they run on e5 they start up with no issues. Maybe try some octane booster

If it was the man sensor then the faults would be all over the cylinders and not on one side I'm guessing

Allen

Post #622647 5th Feb 2022 10:43pm
View user's profile Send private message View poster's gallery Reply with quote
dhallworth



Member Since: 10 Oct 2011
Location: Glasgow
Posts: 3067

United Kingdom 2012 Range Rover Autobiography TDV8 Baltic Blue

Meant to add it’s got E5 in the petrol tank and LPG.

It switches to LPG once the coolant temp reaches around 40 degrees and it’s the same when it switches fuel so I’m not convinced it’s a fuelling fault.

It’s got Flashlube on the LPG system but am kinda wondering if it could be burnt valve seats as it’s been fitted to it for years looking at the service history. Would like to exhaust everything else before taking the heads off though! Smile

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2007 Range Rover Supercharged in Java Black with Ivory Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Post #622648 5th Feb 2022 10:48pm
View user's profile Send private message View poster's gallery Reply with quote
Bean19844



Member Since: 25 Oct 2020
Location: Essex
Posts: 929

United Kingdom 2006 Range Rover Supercharged 4.2 SC V8 Bonatti Grey

Pretty much elimates the fuel if its doing it on lpg. Tried cleaning the maf with some electrical cleaner?

Allen

Post #622650 5th Feb 2022 11:18pm
View user's profile Send private message View poster's gallery Reply with quote
dhallworth



Member Since: 10 Oct 2011
Location: Glasgow
Posts: 3067

United Kingdom 2012 Range Rover Autobiography TDV8 Baltic Blue

I did just after I got it when I was going through everything else on it. Certainly haven’t done it recently so will give it another go Smile 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2007 Range Rover Supercharged in Java Black with Ivory Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Post #622654 5th Feb 2022 11:34pm
View user's profile Send private message View poster's gallery Reply with quote
Bean19844



Member Since: 25 Oct 2020
Location: Essex
Posts: 929

United Kingdom 2006 Range Rover Supercharged 4.2 SC V8 Bonatti Grey

If that don't work, pm me your home address and I'll send my one up to you so you can test it at least and see if it works.

Mines off road atm so can't use it anyway

Allen

Post #622655 5th Feb 2022 11:36pm
View user's profile Send private message View poster's gallery Reply with quote
dhallworth



Member Since: 10 Oct 2011
Location: Glasgow
Posts: 3067

United Kingdom 2012 Range Rover Autobiography TDV8 Baltic Blue

Thanks Allen Thumbs Up

I’ll do a bit more checking and see what I can find.

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2007 Range Rover Supercharged in Java Black with Ivory Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Post #622660 6th Feb 2022 12:43am
View user's profile Send private message View poster's gallery Reply with quote
oggy



Member Since: 09 Sep 2020
Location: padstow cornwall
Posts: 395

United Kingdom 2007 Range Rover Vogue SE 4.2 SC V8 Java Black

same as allen i use ipa in a spray bottle and then drop it on a heater or rad to dry i fitted a k and n filter so do mine every month to clear away any oil that may come from the air filter new vehicle purchase
2007 supercharged 4.2 java black .sand leather vogue se trim
previous cars .
range rover classic 200 tdi
discovery 1 200 tdi
freelander 2 2008 hse
discovery 1 300 tdi
p38 4.0 ltr man r380 ex royal support vehicle on v5c
discovery td5 man off roader

Post #622703 6th Feb 2022 11:26am
View user's profile Send private message View poster's gallery Reply with quote
dhallworth



Member Since: 10 Oct 2011
Location: Glasgow
Posts: 3067

United Kingdom 2012 Range Rover Autobiography TDV8 Baltic Blue

Unplugging the MAF will cause the car to run in limp mode but it should stop it doing anything that would be MAF related I’d have thought.

I might give that a go this afternoon.

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2007 Range Rover Supercharged in Java Black with Ivory Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Post #622707 6th Feb 2022 11:52am
View user's profile Send private message View poster's gallery Reply with quote
Bean19844



Member Since: 25 Oct 2020
Location: Essex
Posts: 929

United Kingdom 2006 Range Rover Supercharged 4.2 SC V8 Bonatti Grey

Try clearing the fault codes, disconnect the maf, then start up as it should throw up it's now got a maf issue so hopefully the other ones won't return.

I'm not particularly clued up with how the lpg works in the engine bay but if the fuel/lpg runs through the same injectors could it possibly be some dirty injectors.

Post #622718 6th Feb 2022 12:44pm
View user's profile Send private message View poster's gallery Reply with quote
dhallworth



Member Since: 10 Oct 2011
Location: Glasgow
Posts: 3067

United Kingdom 2012 Range Rover Autobiography TDV8 Baltic Blue

The LPG has its own injectors and everything so there’s nothing shared between the 2 fuels which is handy for fault finding.

Will try and get to it today in between showers.

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2007 Range Rover Supercharged in Java Black with Ivory Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Post #622730 6th Feb 2022 1:29pm
View user's profile Send private message View poster's gallery Reply with quote
dingg1



Member Since: 29 Jun 2013
Location: PORTUGAL
Posts: 1340

2007 Range Rover Vogue SE 4.2 SC V8 Stornoway Grey

Mine had a similar misfire on starting when it was over filling on valve saver fluid, something to look at.

Also if I unplug the maf sensor it stalls immediately

2007 sc

Post #622731 6th Feb 2022 2:12pm
View user's profile Send private message View poster's gallery Reply with quote
dhallworth



Member Since: 10 Oct 2011
Location: Glasgow
Posts: 3067

United Kingdom 2012 Range Rover Autobiography TDV8 Baltic Blue

That’s an interesting point on the valve saver fluid.

How did you diagnose that?

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2007 Range Rover Supercharged in Java Black with Ivory Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Post #622758 6th Feb 2022 4:01pm
View user's profile Send private message View poster's gallery Reply with quote
dingg1



Member Since: 29 Jun 2013
Location: PORTUGAL
Posts: 1340

2007 Range Rover Vogue SE 4.2 SC V8 Stornoway Grey

Just noticed that I'd used a lot more than usual and it was over dosing by a factor of 3, I think it was just getting sucked in on cold start up as it was fine if the engine was still hot. Since I've recalibrated its got no misfires on starting. (its just a drip feed system under vacuum with the inlet after the throttle butterfly, I have a slipstream of petrol above 2900rpm, done 60k on lpg and all healthy) Thumbs Up

Post #622761 6th Feb 2022 4:17pm
View user's profile Send private message View poster's gallery Reply with quote
dhallworth



Member Since: 10 Oct 2011
Location: Glasgow
Posts: 3067

United Kingdom 2012 Range Rover Autobiography TDV8 Baltic Blue

I think the system on mine is pumped rather then vacuum fed. There’s a little unit mounted to the front of the battery box next to the reservoir for it.

I need to get this sorted ASAP now. Tonight when leaving my folks I had the EML Flashing and the “Engine Performance Reduced” message on the dash. It was running horribly.

IID tool showed misfires on every cylinder bar cylinders 4 and 7.


Click image to enlarge


Click image to enlarge


Am still getting the random misfire and misfire within first 1000 revolutions error codes too.

Live Values on the IID shows the Target MAF and Actual MAF to be near identical so am now happy the MAF isn’t at fault. I can see the MAP sensor values changing with varying load too so don’t believe that’s at fault.

The lambda sensors appear to be switching as well so can rule them out too.

For it to be affecting almost all cylinders it’s got to be air or fuel I think as I don’t think it would be ignition.

Allen - when yours is idling, can you hear air whooshing/hissing at the side of the engine on the drivers side? It sounds on mine as if it’s along the rocker cover on the drivers side. I’ve replaced the PCV valve and the orings at both ends of the pipe that runs back to the throttle body and it made no difference.

I’ve also been spraying brake cleaner all around the area and noticed no stuttering or change in the way the engine was idling either.

Am thinking of getting another smoke test done at the local specialist but asking him to do it when it’s stone cold rather then when I’ve just arrived as it runs fine when warmed up.

I’ve just finished putting the dashboard back in one of the P38’s after doing the heater matrix today so hopefully I can get this inside this week and get a proper look at it as I really don’t want to use it until it’s sorted.

David, 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2007 Range Rover Supercharged in Java Black with Ivory Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Post #622780 6th Feb 2022 6:59pm
View user's profile Send private message View poster's gallery Reply with quote
Post Reply  Back to top
Page 1 of 4 1234>
All times are GMT

Jump to  
Previous Topic | Next Topic >
Posting Rules
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum



Site Copyright © 2006-2024 Futuranet Ltd & Martin Lewis
fullfatrr.com RSS Feed - All Forums


Switch to Mobile site