Member Since: 04 Oct 2018
Location: Wiltshire
Posts: 50
Reduced Performance when towing caravan
2016 D4 Landmark 18000 miles. Purchased new two years ago with no problems. We regularly tow our twin axle caravan (2000kg) again without problem until two weeks ago when towing down the M4.
Red triangle warning with message "reduced performance". Vehicle lost power and went into limp mode.
We took the opportunity to switch off whilst in the queue for the Severn Bridge which cleared the fault and restored normal performance but within ten miles the problem re occurred. Stopped at services and called LR assist who attended within 15 min. (This was a LR technician, not AA patrol) Having plugged in the diagnostics returned fault code P2279 air intake leak. The connection to the throttle body was suspected so this was removed and replaced ensuring the O ring was fitted correctly. The service chap followed us for 30 miles then went on his way with a thumbs up from us. Too soon, the problem returned and we limped to our destination and unhooked the caravan. The vehicle performed flawlessly driving some 350 miles solo over the next week. During that time I booked an appointment with Greens at Haverfordwest who read the same stored code and said they had refitted the air intake pipe to the throttle body. Drove back to the campsite and put another 200 miles solo without issue. On the journey home towing the caravan we had covered 40 miles and the restricted performance and limp mode returned. The following day vehicle was booked into local dealer for service and they investigated the problem. Was told they had performed a smoke test and could not detect any air intake leaks and had checked the connection to the throttle body. I took the vehicle for a test run with the caravan in tow and the problem returned within 40 miles. The dealer had the vehicle back and changed the throttle body which took a week. Again took out on a test tow and covered 80 miles when the fault re occurred. Now back in with the dealer.
Summary, vehicle drives perfect solo but triggers reduced performance when towing after 40-80 miles. Switch off and on again restores performance for 5-10 miles before fault returns.
Dealer seems to be struggling to find the root cause of the issue and says they will have to contact LR.
Meantime they have loaned us a brand new RR Velar but we need our D4 back in good order.
Looking for advice on what the root cause may be. Thanks.
4th Oct 2018 4:31 am
IndusD4
Member Since: 01 Dec 2011
Location: Sydney, NSW
Posts: 308
Maybe a split in the air intake hose? I've had that and the car drives ok when pussy footing around but as soon as you step on it you'd get restricted performance. Mine was the big hose from the intercooler to the top of the engine. There's a smaller one on the other side as well.2016 D4 TDV6 Corris Grey
IIDTool BT
4th Oct 2018 4:51 am
Desb
Member Since: 04 Oct 2018
Location: Wiltshire
Posts: 50
Thanks, I am inclined to think the same but would of expected the dealer to have found this during the smoke test. I also considered a cracked intake but apparently this issue only affected earlier vehicles.
Are you using cruise control when this fault occurs?A vaccine does not stop you catching a virus, or passing it on, or getting ill from it, really ill. It does reduce the likelyhood of you dying when really, really ill. Stay Alive - KEEP AWAY FROM PEOPLE.
4th Oct 2018 8:53 am
riverblanche
Member Since: 31 Aug 2010
Location: retford'ish
Posts: 2230
Hi and welcome,
dont know if this will be much help as we had the same issues but with a D2 TD5 so some time a go
solo it was fine, tintent gave fault when working harder (up hill) it gave faults as air inlet or air flow sensor
but
turned out to be the Turbo waste gate that was sticking, we did manage to free it but it was a work or break type of fix
again you would expect dealer with todays diagnostics to be more informed
Transit! 2019
Gone D3 HSE 2008
Another Porsche Cayenne 2022
Gone Porsche Cayenne 2020
Gone RRS HSE Dynamic 2016
Gone RRS HSE LUX 2011
Gone RRS HSE 2006
Gone D3 SE 2.7 2008
gone D2 Td5 1999
I plan on living forever and so far so good !
Club DG Mclaren stuff
.
4th Oct 2018 9:01 am
Dexter
Member Since: 21 Sep 2007
Location: Aberdeenshire
Posts: 1394
Had a similar fault with a D3 when towing, turned out it was the auto box temperature sensor throwing a wobbly, reporting a false high temp and reducing performance. Only happened when towing the 1800Kg tintent.
Dex
4th Oct 2018 9:17 am
Desb
Member Since: 04 Oct 2018
Location: Wiltshire
Posts: 50
Navigator wrote:
Are you using cruise control when this fault occurs?
No, normally happens when cruising at 60mph or lower. Not necessarily going up hill either. Normally faults after 3/4 past an artic in lane 2.
4th Oct 2018 12:06 pm
Desb
Member Since: 04 Oct 2018
Location: Wiltshire
Posts: 50
Update.....email from dealer....
Hello,
The code we keep getting is P2279-64 – air intake leak bank 1 – signal plausibility failure.
By the looks of it the car has pushed off the air duct again that goes to the throttle body, we believed the clippings of the body were weak hence the replacement. We have a new duct to fit into the end of the throttle body, this should be the issue that will be resolved for you. When the engine boosts through the throttle body a positive charge of air is created and because the plastic clips on the duct aren’t strong enough to hold, it find the weakest point and blows off the duct.
I hope the above resolves the issue, will update after road test with caravan in tow.
4th Oct 2018 7:13 pm
UffBrock
Member Since: 18 Mar 2011
Location: Oxfordshire
Posts: 157
You have my sympathy but that's about all I can offer I'm afraid.
I suspect that you saw my recent posting on the same subject. Since my last post thereon I've had restricted performance yet again. This time the dealer performed a smoke test, found a leak and replaced both the top intercooler hose and the throttle body. I've just completed a 60 mile tow so, for the third time, I'm hoping the problem is fixed. I did involve CRC because I was somewhat less than delighted that the issue was causing me so much inconvenience and loss of time but whether that influenced the final outcome or not I couldn't say.
The curious thing in my case was that I only ever had problems on intermediate throttle openings – the car ran fairly normally on low throttle openings - and on full ones (e.g. an overtake or ascending a steep hill). Problems started only when I tried to, say, open the throttle a little to maintain speed up a gentle incline or accelerate gently out of a bend. In these situations it felt as if the car was just in the wrong gear.
By coincidence, I too had experience of the reported D2 sticking waste gate problem. That too, for me at least, arose only in similar throttle states. What seemed to happen was that the sticky wastegate would suddenly spring free, open too far and so try to close, only to stick again. The result, engine wise, was a constant surging motion that would continue until the throttle was either opened more or closed a little.
I'm intrigued to find out what the solution turns out to be in your case. Good luck.
5th Oct 2018 4:10 pm
Desb
Member Since: 04 Oct 2018
Location: Wiltshire
Posts: 50
Thanks for that.
Waiting to hear from dealer when the elbow will be fitted, suspect it will be Monday.
I haven't much faith that their explanation is the root cause. Will find out next week.
Mean time the dealer is fitting new parts at their expense, hopefully they will stumble on the real root cause.
I will ask to see the throttle body and elbow that they have removed to examine the connection. The car is only two years old this week and I can't see how static parts can come adrift and not show a fault code when driving solo but fault when towing.
Can't complain about the Velar they have loaned me, brand new and fully loaded £82k. Thought about fitting a tow bar to it if I have it much longer.
5th Oct 2018 4:50 pm
Desb
Member Since: 04 Oct 2018
Location: Wiltshire
Posts: 50
UffBrock wrote:
I did involve CRC because I was somewhat less than delighted that the issue was causing me so much inconvenience and loss of time but whether that influenced the final outcome or not I couldn't say.
Sorry....CRC = ??? Customer relations centre?
5th Oct 2018 4:58 pm
Desb
Member Since: 04 Oct 2018
Location: Wiltshire
Posts: 50
Update.
Picked up the vehicle from dealer today after they replaced both the throttle body and air intake elbow.
Hitched up caravan and drove M4 and M5. At 180 miles the red warning triangle and reduced performance message was displayed.
Took photos of the connection between the elbow and the throttle body. Before the test run the connection is secure, after the joint has dislodged.
I have said to dealer that they are treating the effect and not the cause.
I also no test a surging of the engine on a steady throttle setting.
So any info on what can cause excess pressure in the air intake causing it to blow off the throttle body / elbow.
total guess - and if anyone shoots me down at least they joined in !!
could it be a problem with the EGR valves ?.
Dean
====================================
2011 D4 XS - OBD port protection, RLD spare wheel protector, All LED interiors lights, Timed Climate enabled, iiD tool paired.
2011 D4 Landmark - Stolen from same dealer before I paid for it
2011 D4 GS - Stolen whilst at dealer ... All LED interiors lights, DRLs, Spare Wheel protector.
1996 300Tdi - Eaten by tin worms
9th Oct 2018 6:00 pm
UffBrock
Member Since: 18 Mar 2011
Location: Oxfordshire
Posts: 157
Those look identical to the before and after pics I took. Our D4s are also virtually identical age wise - I bought in August 2016 although, of course, it had been built a few months earlier. It's a weird coincidence.
9th Oct 2018 8:24 pm
Desb
Member Since: 04 Oct 2018
Location: Wiltshire
Posts: 50
I have looked back over your past posts relating to this issue. Did you arrive at a solution or do you still have the issue?
I have studied the loose connection joint and can manufacture a plastic clip which will secure the joint, my concern though is what is causing the excess pressure?
Maybe if the joint is secured this will eliminate the weak link and a over pressure fault will be generated?
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
so some time a go
... All LED interiors lights, DRLs, Spare Wheel protector.
