P38A Getting fed up already (I think)... HELP!

OK, Help and advice please - as much as I hate this kind of post from a newbie!

Having owned several of Solihull's finest over the last 40 years or so (a couple of 86” Series 1’s; Series 2A’s and more recently an 89 RRC Vogue with a 3.9 and manual box). After a 12 year gap, I thought I’d found a good P38.

I ended up purchasing a 4.0 Auto SE with a working LPG kit which now resides just outside Hereford.

A few days after my son had brought it home (several hundred miles running perfectly) we started on a service. New plugs went in, followed by a set of front pads and rotors. We moved to some perfectly level ground for the fluid and filter changes and the incontinent b*tch started puking coolant from the water pump!

1x new water pump and a set of hoses later all was well…

NOPE!

Now we have a misfire and seem to be drinking fuel.

Any suggestions / advice before she gets a Viking Funeral?

Coil Pack? Plug Leads?

Any advice on affordable diagnostic options as well?

Looking forward to your input (apart from “You shouldn’t have gone for a P38!”)

Thanks.

Moosevan said:

OK, Help and advice please - as much as I hate this kind of post from a newbie!

Having owned several of Solihull's finest over the last 40 years or so (a couple of 86” Series 1’s; Series 2A’s and more recently an 89 RRC Vogue with a 3.9 and manual box). After a 12 year gap, I thought I’d found a good P38.

I ended up purchasing a 4.0 Auto SE with a working LPG kit which now resides just outside Hereford.

A few days after my son had brought it home (several hundred miles running perfectly) we started on a service. New plugs went in, followed by a set of front pads and rotors. We moved to some perfectly level ground for the fluid and filter changes and the incontinent b*tch started puking coolant from the water pump!

1x new water pump and a set of hoses later all was well…

NOPE!

Now we have a misfire and seem to be drinking fuel.

Any suggestions / advice before she gets a Viking Funeral?

Coil Pack? Plug Leads?

Any advice on affordable diagnostic options as well?

Looking forward to your input (apart from “You shouldn’t have gone for a P38!”)

Thanks.

Click to expand...

Should have bought a diesel Nanocom is the best diagnostic kit.

Datatek said:

Should have bought a diesel Nanocom is the best diagnostic kit.

Click to expand...

Thanks, Thought so. Just gotta save up for one now (I know, shouldn't have bought a P38 then! Ha!).

You can read (and maybe clear) quite a few of the V8 engine faults with generic OBR reader, but definitely get a Nanocom for the longer term.

If the water pump got incontinent, check the Cam Sensor connector. It's just underneath and could be suffering.

Plugs & leads check definitely worthwhile. Older leads can fail during pulling them from the plugs, especially if the contact was tight. I had one that appeared ok, but was arcing inside. Scope test on spark was how I found the offending lead, but changed them all.

pwood999 said:

You can read (and maybe clear) quite a few of the V8 engine faults with generic OBR reader, but definitely get a Nanocom for the longer term.

If the water pump got incontinent, check the Cam Sensor connector. It's just underneath and could be suffering.

Plugs & leads check definitely worthwhile. Older leads can fail during pulling them from the plugs, especially if the contact was tight. I had one that appeared ok, but was arcing inside. Scope test on spark was how I found the offending lead, but changed them all.

Click to expand...

Thanks. Much appreciated. Will check tomorrow. Wanted to check with folk who know more than me about the particular vehicles & am not afraid to ask. Have generic code reader so might be able to ID some issues. Oddly, not a single warning light on dash or any info in display (& all lights seem to check through with ignition sequence).

By the way, any suggestion as to best folk to use for an additional key/alarm fob? Mine only came with one.

https://crnw.co.uk/. Classic Rides in Wales. They can copy you key & adding different key number so they don’t clash. Call & chat to them first.

Pete.

If you changed the plugs ...Theres a outside chance ,unless done one at a time,,,, the leads are on the wrong plugs

dubbleRR said:

If you changed the plugs ...Theres a outside chance ,unless done one at a time,,,, the leads are on the wrong plugs

Click to expand...

Plugs were done one at a time, thanks. Used to V8 motors (usually Dodge or Chevy) so always do it one at a time. Easy one to make & I WILL go and double check!

pwood999 said:

https://crnw.co.uk/. Classic Rides in Wales. They can copy you key & adding different key number so they don’t clash. Call & chat to them first.

Pete.

Click to expand...

Thanks. Will do.

Moosevan said:

Thanks. Much appreciated. Will check tomorrow. Wanted to check with folk who know more than me about the particular vehicles & am not afraid to ask. Have generic code reader so might be able to ID some issues. Oddly, not a single warning light on dash or any info in display (& all lights seem to check through with ignition sequence).

By the way, any suggestion as to best folk to use for an additional key/alarm fob? Mine only came with one.

Click to expand...

Some more FOB replacement options

https://remotekey.co.uk/range-rover/range-rover-p38-replacement-key/ Known to work, half price of HUFF FOB.


[email protected] New non standard FOB's that work.

OK, getting even more confused with this truck...

I only have current access to a cheap OBD Reader but, when checked it showed the following codes:

P0331 - Knock sensor 2 Circuit Range/Performance Bank 2
P1158 Oxygen Sensor Rich Bank B Downstream Catalytic
P3999 Generic not found in database.

Starting simple, we installed new plugs, & new leads. Checked spark with an inline tester and all 8 are visually very healthy. Unplugged MAF sensor; engine became very lumpy; smoothed out immediately on reconnecting so I assume MAF is OK...

Cleared codes and re-tested. Now NO codes showing, but still lumpy idle & feels like misfire running through rev range.
Idle on Petrol whipped up to 1600 - 1800 rpm, on LPG it drops to around 1100 rpm. Throttle seems to be randomly sticky...

Any suggestions before I throw money at random components? Help!
What's a fair price to have an independent workshop run diagnostics with a 'proper reader'? Anyone recommend someone around Herefordshire? We have no issue doing the work - as long as we know WHAT to spend funds on.

Look forward to your suggestions. Thanks.

What are your short term fuel trims running at?
Should be around and not far off 0 as it adjusts the fuel/air for the cat.
Also a dirty idle control valve.
Any smoke or smells from the exhaust?
Throttle butterfly could also be dirty..

Mark Piercy said:

What are your short term fuel trims running at?
Should be around and not far off 0 as it adjusts the fuel/air for the cat.
Also a dirty idle control valve.
Any smoke or smells from the exhaust?
Throttle butterfly could also be dirty..

Click to expand...

Ok, dinosaur here... How do I test the fuel trims? Will clean ICV. Smells very rich.

Any un-metered air getting in will cause it to run rich.

• Could simply be an air leak somewhere between the MAF & inlet manifold.
• Are the LPG injector pipes properly sealed ?
• Are the O2 sensor values changing up & down or static ? (both of them)

Not sure if generic OBD will show the fuel trims. Definitely better to find someone with a Nanocom.

Mark Piercy said:

What are your short term fuel trims running at?
Should be around and not far off 0 as it adjusts the fuel
Any smoke or smells from the exhaust?

Click to expand...

Moosevan said:

Ok, dinosaur here... How do I test the fuel trims? Will clean ICV. Smells very rich.

Click to expand...

You can't test fuel trims, it's the ecus way of allowing more air into the cat and mixing the ideal fuel/air mix for the engine.

Are the 02 sensors working correctly, i'm assuming you have a 4.0 Gems so it'll be the Titiana sensors which are 0-5v they should switch from 0-5 when running, if they're stuck at 0v which is common then that will explain your rich running, easy to check with an OBD reader.

You can read some of the fuel trim data with a generic reader. Or rather, i can on my Thor engine.

Could you have a leaky fuel injector(s)?

pwood999 said:

Any un-metered air getting in will cause it to run rich.

• Could simply be an air leak somewhere between the MAF & inlet manifold.
• Are the LPG injector pipes properly sealed ?
• Are the O2 sensor values changing up & down or static ? (both of them)

Not sure if generic OBD will show the fuel trims. Definitely better to find someone with a Nanocom.

Click to expand...

Thanks for this information, much appreciated. Will get on and check in daylight.

Thanks all for the advice, working through all that I have facilities to do. It now just seems like I'm chasing increasingly random 'stuff' which changes every time I look at it - fired up this morning & it's now lumpy and has a ridiculous idle - 1400rpm on LPG and 2000rpm of Petrol.

Anyone in/around South Herefordshire who can point me in the direction of a Nanocoms unit to rent use of? I'd just like to know what NEEDS fixing before tearing into a full strip down and rebuild for the sake of it...