S80 RPM signal for LPG ECU

[Tony427]

I'm just starting to wire up the Zavoli Alisei LPG system having completed all the plumbing side, manifold drilling for Injectors etc and have noticed that I need to supply the gas ECU an RPM signal.

Anyone any idea how I would obtain a suitable signal without creating conflict with the cars standard petrol ecu brain?

A google got me nothing as did a search on the UK LPG forum.


As an aside how useful is the trunking under the drivers floor that seems tailor made for an extra gas pipe?

Cheers,

Tony

[Pete_c20]

I don't know the answer but my first port of call would be the Vardis information disc (cheap off ebay) and look at the pages entitled 'engine management system, bifuel). If its similar to an S40 look for 4/26 EMS200 (engine management ) and 4/75 LPG (LPG ECU) for the ECU connections and where the RPM signal comes from. I'd then do my homework on the RPM signal output and the two inputs the signal was going to (one of which is already in use of course) to see if hooking 2 inputs was going to mess up the original output. I'd also scope the signal before and after to make sure.
Let us know how it goes, sounds interesting.

Originally Posted by Tony427

I'm just starting to wire up the Zavoli Alisei LPG system having completed all the plumbing side, manifold drilling for Injectors etc and have noticed that I need to supply the gas ECU an RPM signal.

Anyone any idea how I would obtain a suitable signal without creating conflict with the cars standard petrol ecu brain?

A google got me nothing as did a search on the UK LPG forum.


As an aside how useful is the trunking under the drivers floor that seems tailor made for an extra gas pipe?

Cheers,

Tony

[classicswede]

If the ECU is less than 3 years old you do not need to connect the brown RPM wire.

If it is older than that you will need it, run the wire to one of the coil packs and connect to the signal wire. The signal wire is a different colour to each cylinder and can be identified that way

[Tony427]

Originally Posted by classicswede

If the ECU is less than 3 years old you do not need to connect the brown RPM wire.

If it is older than that you will need it, run the wire to one of the coil packs and connect to the signal wire. The signal wire is a different colour to each cylinder and can be identified that way

Many, many thanks thanks for the info. This was the only thing stopping me from wiring the kit into the car.

The kit dates from 2006 and was fitted to an Jaguar 6 cylinder so I'm doing a bit of refettling.

I've already found an interesting bodge on the wiring whereby the tank fuel guage wire was wired into the switched live supply for the gas tank solenoid. It looked like a permanent fix so I have my suspicions that the tank guage is either kaput, or the previous owner was trying to eke the tank range out a bit more than he should.

Other than that as long as the ECU fires up there shouldn't be too many problems. It might run a tad rich, ( about 10 %) on the Jag settngs until I get the fueling software sorted, but it all seems fairly straightforward.

Cheers,

Tony

[classicswede]

If the level gauge is a 3 wire hall effect sensor then it will need a 12 volt feed.

[Tony427]

Just a quick update on the ebay S80 LPG conversion.

I managed to get the system working correctly by calling on the services of Mat at M.Power in Birmingham who in the space of a cheap hour got the system working correctly and sold me the cheapest LPG I have found in Brum.This guy knows his Volvo's and is highly recommended.

24 hours later I was off on the trip down to the Amalfi coast.

Cruising at an indicated 90 mph through France and 95 to 100 mph in Italy, together with mountain passes, horrific traffic jams and constant air conditioning the car returned dead on 25 mpg on LPG.

I actually did a few more miles than expected and got back yesterday afternoon after two weeks and 3919 miles. The car used 712 litres of LPG for which I paid an average cost of 68.4 pence per litre which cost £487 in total. As I've already said the LPG system was running a little rich I believe but I still saved about £375 on this trip alone compared to what it would have cost using unleaded petrol.

The car performed faultlessly, even under 40 degree heat, sitting in traffic jams and being thraped remorselessly over mountain roads some of them simple dirt roads.

It didn't use any water or a drop of oil, although some cheap front discs I had fitted when I first purchased the car did start to give some brake judder following some heavy braking at speed on the Italian motorways. Now the car has proved its worth I'll only fit quality parts in the future.

Suffice to say regarding LPG I've been "converted" and I'll be looking at doing the same to any other cars I buy. Running on LPG makes even the largest ( and most heavily/ speedily depreciating) V8's affordable.

Cheers,

Tony

[Pete_c20]

Glad to hear it's sussed. And thankyou for the economy figures, always interesting to hear.