Thread: 3.5 EFI ignition module

I don't know the difference, but the EFI system does not control spark on the Rover V8s that are fitted with a distributor (Discovery I and Range Rover Classic).

G`day

So long as your talking Range Rover and not Rover Car SD1 they are almost the same as far as the distributor . Parts can interchange .

There is on the later Discovery 1 a similar style remote amp set up but uses the amp like the dissy mount unit .

The same under coil amp was on 84/5 BA model Carby and 85/6 CA model with EFI . Not sure but it may have been on some 86/7 DA model as well though i think this may have been the change to the dissy amp .

So yes with the right bits either could be used but the later amp is probably easier to obtain and probably cheaper .

We have an 84/5 model with the amp under coil and it`s never been replaced and also never any trouble . I think most dissy amp set ups will have had the amp replaced by the time they reach 24 yrs .

Cheers

Thanks BigJon and PLR. Just noticed that my second last paragraph wasn't exactly easy to follow.

Yes, it's the Range Rover engine - first of the 3.5 EFI Rangies. I had the module on the side of the distributor fail and I was wondering about access and heat in that location, and if the remote one would do the same job. It is a bit hypothetical as I've replaced the module, but I was gathering info for future reference.

Unlike the 1976 2-door I had for years, where I knew every inch of it in great detail, I tend to only learn things on this one (1987) when something dies and I have to fix it.

I took the plastic cover off (inside) the distributor while I had it out and it looks like the pick-up may be magnetic rather than Hall effect. The Haynes manual mentions both.

It's been on dual fuel for about a year and after working on it last weekend I'm contemplating going gas-only and pulling all the petrol stuff off to get better engine access. Not sure yet. Unlike the 2-door, I've never used this one for any serious off-road or outback work. Probably never will now, so reduced range from LPG tank isn't all that important.

The LPG mixer plate is just inserted in front of the airflow meter and I can't see why it couldn't be adapted to sit at the mouth of the intake plenum with an air cleaner right in front of it.

Does anyone have any experience with these electronic distributors, please?

I think it's the magnetic pulse type. It has a metal disc with narrow spikes on it that pass a large curved magnet as well as what I presume to be a pick-up coil with a tiny gap in it, like the head on a tape recorder.

I'm in all sorts of strife. The Rangie ('87 EFI) died last weekend while we were in the suburbs. Just failed to restart. All the signs were that it was an ignition problem. I had no tools with me (long story) so I called the RACV who diagnosed a dead ignition module on the distributor.

It was behaving normally while it was running, and it just wouldn't restart about an hour later.

So I bought a new one during the week and have just finished reinstalling the distributor. But it still won't start. It just cranks.

If I energise the coil directly and attach a spark plug directly to the coil, I can get a spark, so the coil is okay.

I've just pulled the distributor out again and set it up so I can spin it by hand, and I get no spark.

So as far as I can see, there are only 3 possibilities.

1. The new module is faulty.
2. There is a fault somewhere that killed the first module and has now killed the new one.
3. The distributor is faulty.

But if it is the 3rd possibility, what could it be? There is very little inside one of these things and none of it is particularly delicate.

Originally Posted by wlb

I've just pulled the distributor out again and set it up so I can spin it by hand, and I get no spark.

So as far as I can see, there are only 3 possibilities.

1. The new module is faulty.
2. There is a fault somewhere that killed the first module and has now killed the new one.
3. The distributor is faulty.

Did you buy a "fleabay special" module?
Is it the 3 pin module??
Was the old one a 2 pin module??
Did you open up the dizzy and adjust the gap between the "metal disc with narrow spikes" and the "magnectic pickup"??
How old is the rotor button??
Is the rotor button a genuine LUCUS???????
Is the dizzy cap in good condition?
Is the actual coil HT lead working?

Thanks Mike,

I found the problem late last night. The pick-up coil has gone open circuit.

It's a Lucas universal 3-pin module to replace the old 2-pin. You just use pins 1 and 3 as per the diagram in the box.
Air gap hasn't changed and all parts are Lucas and in good condition.

The pick-up was the last thing I expected to go.

Will this distributor work with the earlier remote amplifier module that sits under the coil on the inner guard? (Just out of interest)

As you might have noticed, I had more questions of "Probability" than answers

Originally Posted by wlb

The pick-up coil has gone open circuit.

Unsure which part you mean from your description of part .... Photos would be helpful

Originally Posted by wlb

Will this distributor work with the earlier remote amplifier module that sits under the coil on the inner guard? (Just out of interest)

Can't see why not .... The dizzy doesn't care where the (new 3 pin) ignition module (Amplifier) is located .... .... Photos would be helpful

Originally Posted by wlb

It's a Lucas universal 3-pin module to replace the old 2-pin. You just use pins 1 and 3 as per the diagram in the box.

This can trap some ... as sometimes you can reverse the + & - when making up the connection to the new module ....

Cheers

Mike

Thanks Mike.

No problem with all the extra questions. They help confirm that I haven't overlooked something else, and they make sure we are talking about the same thing.

It's the magnetic pick-up that detects the passing spike of the magnetized "cam" that has failed. Open circuit across the orange and brown wires.

I couldn't see why the earlier type amp wouldn't work either. But the Prince of Darkness moves in mysterious ways. It seems to me that it would be better. It's more removed from heat and vibration. It's bigger so probably doesn't have miniaturization compromises in the construction. It has a better, bigger heat-sink. It's easier to access, test, and replace. Although I can't really complain. The Rangie is 22 years old and it's done 300,000km.

I triple-checked the polarity when I replaced the plug. Then I went away and did something else. (Banged head on wall several times and gave thanks that it was a 22-year-old car I was working on, and not a recent design). Then came back and checked polarity again.