RussWinch

New Member
Hi, I have just realised a boyhood dream and bought an '89 3.5 EFi V8. Only problem is it's a bag of nails and it's been bought with heart not head....but I can see potential. It's a non-runner but will run on Easy Start which I know hides a multitude of issues. I read that the Lucas 4CU takes a coil signal to fire the injectors, however I only have two coil connections, whether this is right or not I don't know. I could do with someone with some technical knowledge to have a look, for which I would happily pay - but finding people who are happy to look at older stuff is seemingly quite a challenge. I'm based in Bromsgrove, UK. So if there is anyone here who could give me any time I'd be really grateful.

In the meantime I'll go back to creating more holes in the bodywork, hopefully there will be some good metal to weld to but I'm starting to lose hope
 
I've not taken an injector out yet, have disconnected fuel line so far and fuel is flowing when flapper pressed.
 
Welcome to the forum & congrats. for buying a 'proper' RR ;)

Whilst the 3.5 isn't the quickest of Rover V8's it is the most reliable & as an '89 yours' would be amongst the last, the 3.9 being introduced in Sept/Oct of that year.
I've owned three 3.5efi Classics over the past 19 years plus a 3.9 previously. All the 3.5 examples have been reliable (can't say the same for the 3.9) so I've never experienced your problems. I don't work on cars these days but am lucky enough to have a trusted local garage for servicing/MOTs.
There is a wealth of knowledge on this forum to help you, be patient & good luck with a motor that will bring a smile to your face once it's sorted.
 
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The 4CU doesn't do anything with the ignition, just the fuelling & basically controls the amount of time the injectors open. They open in banks of 4, not individually.
On LPG I don't even need the ECU connected & that's proven handy as a diagnostic tool - if it runs badly on petrol but fine on LPG then it's a fuelling issue (I've had 4CU ecus die), if it runs badly on both it's ignition.(duff plug or lead in my case)
So as it will run on easystart you at least know that side of things is OK.

There are a lot of tests that need to be carried out & you need the paper LR workshop manual for these models.
That said, substitution with a known good ECU is the quickest to detect a duff ECU.
Have a read through this thread: www.landyzone.co.uk/land-rover/classic-1989-3-5-efi.383797/

Don't be tempted to take the top off the air flow meter. The fuel pump should only run on cranking OR if you hold the flap open.
When the car fires & runs the flap will be held open by the air being drawn into the engine.

You should have a 9th injector on the right hand side of the plenum chamber. Serves no purpose in our climate but could be putting too much fuel in when you're trying to start. Unplug its lead.

Website here worth a look: Rover SD1 Efi Electronic Control Unit (ECU) (vintagemodelairplane.com)

The manual is: 'Range Rover All petrol and diesel models 1986 to 1989' ISBN number 9781855204430. Land Rover part number SRR660ENWM Not cheap, but mine's saved me a fortune over the years
 
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