V8 5L - Thoughts on P0016 a year after chain change

[heliart]

I did the chains and guides on my V8 5L last year at about 70K miles. Chains, guides etc, but did not change the VVT sprockets - they were very clean (no sludge).
No other issues for over a year, and oil changes every 6 months (so two since). Only done 6K this last year.
I've had P0016 bank 1, sensor 1 twice, about a month apart recently. Only on a cold start (within 1 min of starting the engine). Also the car had typically been sat for a good few days unused before hand.
Clearing the codes OK.
Never had this while driving or in daily out and about start/stop use.

I just last week swapped over the bank 1 cam sensors and cleaned up all the contacts.
I was also thinking about low battery causing sensor issues, but having two P0016 codes seems unlikely.

I'm not sure how to diagnose, other that firstly swapping the sensors and solenoids over.
Question is on the diags method for a failing VVT sprocket or solenoid. I assume you read the timing (I've a GAP tool), but as there's not error in normal use, is this still useful.

I really want to lean how the VVT system works. Advice welcome?

Thanks.

 

[powershift]

If you stick your finger in the oil fill hole, can you move the chain?

 

[heliart]

Chain is fine, as far as I can tell without pulling the timing cover again. Certainly runs totally quiet - before the change it has a lot of slap.
No repeat of the code since swapping the cam sensors and cleaning up all the topside engine connectors.
I'll keep an eye.

Probably, it it does it again, I'll have to get in and have a look, but as those who have done it, that's a fairly major job.

 

[djkaosone]

When reinstalling the VVT, did you torque it down per workshop manual?

 

[powershift]

I had a cam code on my 5.0L after a shop did my chain. The engine needed to be under load to fail. Punching a hole in the air on the freeway would do it in 4th pretty much every time. But the event included the limp mode or whatever the Land Rover speak is. Onramps would trigger it too sometimes.

 

[Longtrail]

@heliart - Misery loves company! I did my chains just over a year ago (Dec 2024) and yesterday got the exact same error code; it started with an engine light and restricted performance but then the restricted performance switched off. It's a similar situation in that it's very cold here (probably circa -10C) and the car had been sitting for a few days. I ran errands and after about the 5th start/stop the engine light went out. When I drove it again today it was fine. I followed the workshop manual very carefully.

For now I'm in a holding pattern to see if it comes back.

Running the V8 must be costing you in petrol money?...

 

[heliart]

As a follow up.
@djkaosone - yes, did the torque on the VVT as per the manual. I remember well enough as it was a two man job (me and the wife anyhow) to hold to torque while tightening.

Still had no occurrence of the code since swapping the cam sensors and cleaning all the connectors. We've had a wide range of temperatures here in the UK this past month, so does not seem to be temperature related. Been using the Disco most days, where as I have a feeling that the last time it had the code the car had been sat for a few weeks. I'll keep you posted.

@Longtrail - yeap, running a V8 here in the UK on super unleaded is rather pricey. It's a great Winter car though. I tend to mix it up in use with my 2015 Defender 110 to average out the fuel cost of running it. Don't tell Greta, ~15MPG is about average I think.

 

[ugmw177]

Here is my theory [but may be bunk]. Our v8 has not had chains replaced but seem tight and no noise. a year or so ago during a cold morning at first startup, son kind of goosed it to get out of intersection near home. it popped up a p0018 and restricted performance. restriction went away after a few seconds and i reset the light later that morning. Has not happened again. I think the tensioners had either bled some oil off from sitting or the oil was too thick [cold] to really build up proper pressure when cold at first start. I understand the oil passages are very small. In any case, good luck on this.

 

[Longtrail]

@ugmw177 - I think this is a good theory, I tend to go very easy on mine during warmup (and actually the rest of the time as well), anyway; this particular day when it happened we'd had a decent amount of snow, I was in the mood for a little fun and reckon I may have gone a little faster than normal, I had similar experience with restricted performance and then the light eventually going out after a few engine on/engine off cycles. I've not seen the issue since and have been purposedly more gentle on it.

@heliart - Ouch, 15MPG and the UK gallon is bigger than the US gallon, I think it's 4.54L vs 3.89L; I reckon I'm getting 15 to 18MPG (US Gallon); anyway, greetings from across the pond.

 

[LR4 2011]

VVT are probably sticking. I had to replace my VVT on bank 2, the code left and it has run fine.