Oil in the plug wells will be the tired old rocker gaskets that need replacing. A common issue.

We need to get some readings from the MAF before you decide it (they) are no good. The below figure are confirmed good readings from a 4.6 THOR. Make sure all loads are off the engine and its up to temperature. Idle 680rpm - 22Kg per hour 1200rpm - 32.5Kg 2000rpm - 55Kg 3000rpm - 92Kg...

We did buy a genuine MAF didn't we?

I found all pumps are not made equal.

Petrol / Diesel ?

Look at the MAF to start with, look for 22kgs /h on idle with all loads off. If you've got anything different report back

I would search on here for post by Mattstevens, he had this issue I believe when he got his.

Genuine only. Trust me on this.

Im not aware of any units yet that keep the OBC operational.

If you have dsp, then not easily. You will have to wire back to the BM54 radio module in the back if you have nav already and my experience of these Chinese units is not good. They sure do all they say, but are very clunky to use with poor touch (stab) screens and a real lack of finesse. I had...

I did have a self installed one, still got the manuals somewhere and maybe even a MAP.

That's way to hot with that stat. mine never goes over 90 now. These babies don't like cheap water pumps either.

v8 ? Ill wager one of the secondary air injection pipes isn't seated properly.

I used to have that kind of optimism. 6 Range Rovers later......

No sound can be a dodgy resistance in the steering wheel controls sending the wrong signal to the head unit putting it in MUTE mode.

Ive had this on mine. My boys an MOT tester and recently went on a refresher course and asked the question. If its presented on LPG it gets tested on LPG and therefore comes under something something (cant remember the wording) and will be fine - This is from the VOSA man running the course...

Straight to the ECU

Yes. The Motronic ecu will report a fixed value of .5v if it doesn't receive a valid signal from the O2 sensor. The cheapest way to test is to get the old girl warmed up and get underneath and probe the o2 sensors with a multi meter. You will have 4 wires going to each one - two white...

I think yours is on the turn from GEMS to Thor engines. Earlier Gems have Titania O2 sensors that read from 1 to 5v volts where as the later Thor have Zirconia sensors that read from 0v to .8v two totally different systems. Gems engines can take a long time to settle after major surgery to the...

The screen is just that, an interface for the radio module ( bm54 ) and the sat nav. It's not unknown for the pcd to fail in these maybe helped by a spike from a wet amp. This would explain why the radio still works although you have no display. As Saint says, interrupting the power to the nav...