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Keithy P38
17th April 2023, 05:34 PM
G’day lads and lassettes,

It’s been a while since I’ve been on the old AULRO - is that a sign of a reliable P38 Rangie 🥴😉

Chasing help with the LPG system. The vehicle is a Thor 4.6 HC P38 Range Rover. I’m not entirely familiar with the bits that complete the system, however, I’m aware of a misfire issue. It’s cylinder 4 & 8 that are misfiring on LPG. On petrol - no issue. The coil packs have only done about 20,000km since I replaced them.

The system is an Impco BRC Sequential system. The system was installed by Graeme Cooper circa 2012 by the previous owner. I’ve done over 100,000km with this system in operation with the only drama being a dodgy plug lead or two. I’ve been a good boy and regularly replaced the leads with just the standard issue black ones - nothing special (I’ve been told that just standard leads are fine, as they have been for me). The spark plugs are NGK BPR6ES (standard plug is a 5, hence I’ve been running the 6 for gas most of the time). The plugs have been replaced this week. I run them with a 0.7mm gap. Previous plugs did 10,000km and went from 0.7mm (when installed) to 0.9mm after the 10,000km they did.

I’ve had a little look around and everything is in place still, nothing unusual happening other than the misfire.

Attached is a pic of (correct me if I’m wrong) the injectors. I am aware that the labels are not in order of firing order, but rather installation order (my mechanic did this many years ago when I had it worked on).

Can anyone identify these injectors, and know where I can purchase them new? I am open to suggestions if you think it may be something else, however, I’m almost certain it’s the injectors.

Cheers
Keithy

I Love My Landy!
20th April 2023, 07:23 PM
Hi Keithy,

I have had a lot of experience dealing with misfiring over the years with my 3.5L County on LPG, but that is running carbies and a distributor, so i don't know how much help i can give you with your set up. I will say this though:

- the NGK BPR6ES plugs are the most reliable plug i have used over the years. I did have a regular misfire issue and during that time i swapped from NGK plugs to Bosch plugs (WR7DC+) to try to solve the issue. In the meantime I found that the root cause of the misfiring was a sloppy distributor, which i replaced. Anyway, the Bosch plugs seemed fine for a few years, but then I started having issues with misfiring again after only a few thousand km's of each new plug set. Turns out they are made in Russia now. I have since gone back to using the old NKG plugs (which I had kept) and I have had no more spark plug related misfiring despite them being second hand! I get about 30,000 km out of a set. I gap them at 27 thou (just under 0.7mm). The gap doesn't widen anywhere near as much as yours do though! (Not sure what is going on there...)

- I use the black Bosch inductive core leads from the shelf at supercheap auto. They seem to work well - In the last 8 years i have only ever had 1 dud lead. I replace them at 100,000 km for peace of mind, but I keep them as spares because i reckon they would still be fine. The only issue with them is you need to make sure that they are kept as sperate as possible as where they cross over can cause misfire. I was told years ago by a Rover mechanic and an ignition expert that you need to keep the ignition leads off anything metal or anything black in an engine bay as carbon would commonly be used to colour these black components. Anywhere my leads cross over I either use a lead separator clip thingy or just wrap the lead with some old ignition lead boots.

Anyway, i hope my ramblings have confirmed some of your thoughts with your electrical componnets. All the best with it!

Edward

Keithy P38
24th April 2023, 09:37 AM
Thanks for your reply mate, and your very thorough information! I really appreciate it.

Just as an update to the situation, I’ve ordered a 4-pack of new injectors from Turkey. They’re due to arrive mid-May (yes, that’s a long wait!). I’ll update when I’ve changed them out as to the outcome!

Cheers
Keithy

Keithy P38
18th May 2023, 09:28 PM
UPDATE!!

Two new LPG Injectors fitted, no more issues. I’d say at least one of them has been buggered for LITERALLY YEARS. It’s got much more URGE.

I’ve taken the opportunity to make a “somewhat candid” video on my YouTube channel for anyone interested. I’ll put the link up in a few days.

Cheers
Keithy

Pedro_The_Swift
20th May 2023, 06:36 AM
Any chance you can put the injector supplier and part number here for others?[wink11]

Keithy P38
25th May 2023, 05:05 PM
Sure thing mate.

This is a link to the Seller on Ali Express:

AUTOGAS WORLD Store
AUTOGAS WORLD Store - Amazing products with exclusive discounts on AliExpress (https://a.aliexpress.com/_mqPzBKc)

And this is the injectors:

4 Pcs LPG BRC Injektor CNG GPL IN03 BRC Yellow Fast Nut Albien Injector 09SQ99020003G
4 Pcs Lpg Brc Injektor Cng Gpl In03 Brc Yellow Fast Nut Albien Injector 09sq99020003g - Fuel Injector - AliExpress (https://a.aliexpress.com/_mNq8z9K)

Picture just in case!

Cheers
Keithy

Keithy P38
25th May 2023, 05:09 PM
Here’s a video link - Part 01:

V8 MISFIRE HUNTER - Can You Guess Why? OWN this GAS Problem
V8 MISFIRE HUNTER - Can You Guess Why? OWN this GAS Problem - YouTube (https://youtu.be/hgMxk6x7kn8)

Keithy P38
30th May 2023, 09:23 AM
And here’s the second video. Hopefully a success!?!

Cheers
Keithy

GAS BUSTER - I Ain’t Afraid of No GAS!
GAS BUSTER - I Ain't Afraid of No GAS! - YouTube (https://youtu.be/js8cuHGq-VY)