Hi, I suddenly started getting misfire on cylinders 2,4, and 8 and a “random misfire” on my ‘12 Supercharged. Codes as per my Gap IIDTool.

I checked all codes yesterday because I heard a thump from the rear and wanted to see if there was a code on the air spring or shock and there were no engine codes at that time. (This may have been a random thing thrown up by the tires that I didn’t notice in the road?).

It has a slight hesitation when in low RPM and going uphill until it downshifted, for the last 2 days.

I drove a fairly bumpy dirt road in the American Southwest this morning and the check engine light came on when I restarted the car after a 20 minute snack break after an hour or so of that road. That’s when I checked the codes and saw these.

So my thinking is something may have been knocked loose on the bumpy road especially since those are all on the same side (I believe the right side of the car?).

Given that all those cylinders plus the random one started at the same time, I’m guessing it is not a bunch of coil packs or spark plugs or injectors that all decided to quit at exactly the same time.

I can’t hear a vacuum leak but am getting a ticking at idle.

No smoke at all but there is a slight smell of what may be burning oil if the car is running hard like extended uphill in the mountains out here.

I filled the gas tank just before driving the dirt road so wondering if maybe bad fuel?

Any recommendations are greatly appreciated!

Click image to enlarge

Here are the codes as in the image, to aid in people searching in the future:

PCM-Engine Petrol

P0302-00 (AC) Cylinder 2 misfire detected
P0304-00 (AC) Cylinder 4 misfire detected
P0308-00 (AC) Cylinder 8 misfire detected
P0300-00 (AC) Random misfire detected

Nm

Last edited by MilesBFree on 13th May 2025 11:25pm. Edited 1 time in total

Just for grins, i started the car without the connector plugged back in. Runs about the same and the codes are the same.

So I’m thinking the sensor or the wiring may be the issue

A sensor won't do any harm to try but the 5.0 engine is known for timing chain issues. They are caused by wear on the guides from the stainless steel pin on the tensioner. It's a well documented issue and one I've come across on my own car.

What year is your Range Rover and how many miles has it covered?

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone 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
2013 Range Rover Sport SDV6 HSE Black Edition in Santorini Black with Ebony Interior

‘12 5.0 Supercharged.

Previous owner claims timing chain and related parts were done about 25k miles ago

You may be correct but the code was clear that there is a problem with the sensor so it won’t hurt to check that now - might be a cheap fix. Or i may still need to do the chain AND the sensor

Last edited by MilesBFree on 13th May 2025 11:35pm. Edited 2 times in total

Mine was a 2012 that needed the chains doing too.

That really sucks if they've only lasted 25k miles. How long ago was it time wise as the repair could still be under warranty if it was done at an LR dealer as all LR parts come with a 2 year warranty.

If they've not been done with genuine LR parts then 25k miles could well be good going too as I've heard they don't last long at all.

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone 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
2013 Range Rover Sport SDV6 HSE Black Edition in Santorini Black with Ebony Interior

Also, you've got 4 camshaft sensors on that engine. You could swap them around rather then buying a new one and see if the fault stays with that bank or follows the sensor.  2002 4.6 Vogue SE - Alveston Red with Lightstone 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
2013 Range Rover Sport SDV6 HSE Black Edition in Santorini Black with Ebony Interior

Good idea!

I believe the A sensor is the intake one so if the problem moves to B then I’ll know

A new sensor fixed the problem. All codes are gone and the car is running great again!

You need to do a few short drives and turn the engine off after each one before restarting, to get the computer to reset / relearn (that is in addition to simply clearing the code with the scanner). Apparently the computer stores the previous values it was reading before and it takes a few driving cycles to replace the old values (I may be wrong on the reason but a few search results referenced this “drive cycling).

I bought a Bremi brand sensor, which I believe is OEM, I think they renamed the company or maybe bought the tooling or something similar. The old one I pulled out is labeled as Denso, but that could have been replaced when the timing chain was done 25k miles ago