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3.9 efi lpg auto 92'

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Problem is, v8 starts runs rough and misfires when rev it up, removed plugs ngk's,  wire brushed checked gaps 0.65 leads silicone type, also removed distributor cap cleaned ect, I found that the flash shield had a piece missing out of it and badly cracked, if I follow ht lead diagram I found on Google it won't start at all, can I buy a flash shield, and where from, dd

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In the Haynes manual ūüėõ¬†

Seriously, on side of dizzy, do a search it has been covered umpteen times on here.

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I had the same sort of issue, changed amp etc, then problem seemed to be petrol pump. After much investigation turned out to be ignition coil, partially but not totally failing!

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Has it always run rough or just started?

Does it run badly on both LPG & petrol?

The lead diagram you followed might be wrong or you may have misinterpreted it. Possibly the dizzy has been removed & refitted incorrectly (easy to do) & the leads have been moved. If only 1 tooth out it can pop & fart (guess how I know!). Best way to check is to set No 1 at TDC (rod down plughole) with both valves closed & see where the rotor arm is pointing.

Have you removed & replaced the rotor arm? If you turn the rotor arm gently with your fingers & release it does it go back to its original position or stay where you moved it to?

Is the rotor arm of the type with the metal strip riveted to the plastic (bad) or with it moulded into the plastic?

Worth trying to start it in the dark to see if you have an electric firework display on any of the HT electrics as this can indicate tracking.

IIRC the shield comes in an overhaul kit RTC5971.

Check that you have no major airleaks on the intake side. I had the ram housing to extra airvalve hose split on mine (flapper EFi) & it just didn't want to know on petrol, as in no power as the AFM couldn't see the extra air so the mix was very very weak but was fine on LPG.

ETA Mine's on LPG - manually switched so I decide when it runs on which - & I use it as a diagnostic.

If it misfires on LPG but fine on petrol it's an ignition issue - to date that's been 2 duff plugs.

Fine on LPG but rough (or not at all) on petrol then a fuelling issue  - to date 2 duff 4CU ECUs & a failing wiring connection to the fuel pump.

Rough/misfire on both then it's ignition & that was a pattern dizzy cap that was all I could get at the time. Symptom was a miss at speed/under load towing on both fuels, worse in wet weather. Fitting a proper cap sorted it. There were significant internal structure differences between the 2 caps.

Edited by paintman

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interesting reply paintman, first of all it came to me on a recovery truck range rover had been standing for couple of years, drove it off truck to driveway 30ft very rough put new fuel in 25litres kept trying it for couple of days running but rough when revving it was miss firing at high revs, removed plugs cleaned distributor descaled couldn't get rotor arm off so cleaned brass strip with sand paper all back together still the same

1  checked lead diagram different from my layout so changed it to suit wouldn't even start, turning over  (had diagram from tech archives, see attached pic) so i had to move 8 to where no'1 was and 4 where no'8 was and so on then it would start but really rough

2  tdc test rotor arm pointing to no'1 spark plug if i turned it like you said yes it goes back on its own, tried to remove rotor arm but stuck fast and brass strip which was riveted on came off, so collecting one tomorrow

3  got rotor arm off at last and the shaft had rust stains on it and metal strip inside of arm was rusty

previous owner has put a ignition amplifier on it by the coil on the nearside wing its been done badly with two core electrical cable something you see on a fridge and use them square connectors with grub screws on the top

i have no lpg at the moment re moved tank to do some welding refitted but empty

i will see what new rotor tells us tomorrow and up date thks for your advice, dd

 

ht leads.jpg

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You'll find ignition system tests & checks incl the amplifier in the RR manual. I believe yours will be on RAVE (a CD)which I think can be downloaded free or bought on ebay etc. I'd suggest you get one as it will make life easier.

Unless you're totally happy with it I would be inclined to reset the timing just to eliminate it as a source of issues. I remove nearside (UK) rocker cover & No1 plug, then with a long rod in No1 turn engine until No1 piston at tdc. Check rotor position. If you do remove the dizzy be aware that the drive gears are skewed so the rotor arm will move as you pull the dizzy. As yours is running - albeit roughly - you might want to mark pre-removal position of dizzy body to block & the pre & post removal position of the dizzy arm relative to the body of the dizzy. I use white paint applied with a paper clip or bit of mig wire. Means you can put it all back in the same position.

Check the new rotor arm turns & goes back when released.  I should have mentioned that you need to press down on the reluctor - the 8-pointed star thing under it - as you pull the arm off or you can disengage the auto advance/retard in the lower cup of the dizzy. If necessary with a stuck rotor arm breaking it off in chunks is sometimes the best solution. If you have dislocated it you don't need to remove the dizzy but be sure to pack rags around it to stop any bits falling onto the engine & disappearing in the various nooks & crannies.

The 3.5EFi used the amp on the inner wing under the coil. The later ones had the amp on the side of the coil. Due to heat issues damaging it RR eventually came up with a remote kit to mount it on the wing!  https://www.rangerovers.net/repairdetails/classic/electrical/ignitionmod.html If yours has had a bodge then this needs checking & possibly the amp replacing as mentioned earlier (tests in the manual) but I prefer to check the mechanicals are correct first.

Your lead order & layout pic looks fine.

Edited by paintman

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 My engine will not run to the lead layout in the picture, had to move every  lead back by one position, also that 8 star in dizzy has half inch lift in it is that ok, dd

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OK. Leave the leads as they are. If when you checked the rotor arm points at your No1 when it's on firing stroke at TDC & the rest number in the correct firing order I don't THINK that will be an issue.

Don't know on the 1/2 inch vertical movement. Is that the whole shaft moving up? I do know the reluctor should engage with a circular plastic gizmo on the shaft underneath it that determines its position on the shaft. Pulling the shaft up is likely to disengage the advance/retard - I did this some years ago before i knew about holding the reluctor down. I can't remember how high the shaft came up as it's a long time ago but I do know I had to remove the baseplate to reconnect the springs & weights & that it all went back together OK.

It should NOT be doing what you see in this clip: https://www.bing.com/videos/search?q=range+rover+classic+distributor+strip&view=detail&mid=B6BB61529EEBE6B2A0FFB6BB61529EEBE6B2A0FF&FORM=VIRE he's disengaged the advance/retard & the rotor arm doesn't return when released. As I said earlier.

I don't seem to be able to find a strip & rebuild for the 35DLM8 distributor.

ETA been looking for this! He had the advance/retard disconnected problem - not the over-fuelling he thought.  If you try to go to page 2 & it just says 'Loading' but nothing happens just use your browsers 'refresh' symbol & it should do the trick.

 

Edited by paintman

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Reading the post on the link, in one section it says rotor arm facing no'1 plug lead on the dizzy is this correct, my rotor arm is facing no'1 spark plug in the engine block? Looking from front of engine mine is 2.oclock, link says 4.oclock, is This my problem, dd

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With No1 at TDC - both valves closed on compression stroke - the rotor arm should be pointing at the position the lead that goes to No1 plug occupies in the dizzy cap.

All other leads are positioned relative to that. If a lead is out of position then it may start & run but it will be rough - been there done that.

As it runs, have you tried removing each lead in turn to see if it makes any difference - be careful & use something well insulated to avoid shock. If a lead removal makes no difference then it could be lead or plug. To confirm move the plug to a firing cylinder & see if the problem moves with the plug. Then do the same with the lead.

On mine - 1986 3.5EFi - as viewed from the front of the car No1 lead position is at approx 4 o'clock same as the line drawing in your earlier post.

Looked at from above and from the front of the car on mine & the later dizzys the vacuum unit is to the 9/10 o'clock There are two clips that hold the dizzy cap on. One is towards the 12 o'clock. The other is immediately to the 6 o'clock of No1 & between the leads to No1 and No8.

Have you fitted a good rotor arm & if so what has happened?

You need a manual as you need to work through the electrical checks.

Edited by paintman

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Update, well I found that the pick up in distributor were touching and when I turned the 8 star wheel I could here it clicking when it touched so set it to 0.2mm when I tried to start it the starter motor packed up, so don't know if it's sorted yet, the starter just clicks and sounds as if battery is dead but it's fully charged 12. 60 volts, tried it straight direct from battery to starter still the same so don't think it's. Ignition fault, when trying starter noticed smoke coming from the earth  on the condenser a d the bolt was hot, short black wire goes to coil, dd

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