Conversion of a Volvo V70 (P80) 1999

[CNG]

It occurs to me that the one thing that will throw even the best at fuelling... is the blinkin' fuel itself. You see, it varies. I've one of those Innovate Lambda gauges in my classic, which might seem a little incongruous, however it's told me quite a bit.

NG is not consistent, now my words might come out as total bull when seen in the better metered environment of this Volvo, but... Presently running in my classic via a single-point set-up, it could easlly be the vagaries of the open-loop system, but I think not.
My gauge tellls me the fuel varies slightly from day-to-day, one fill to the next. Not by much, but it's there.

Iveco, via Tesco's fleet have observed this;

The fact that biomethane is derived from material discarded by society makes it particularly environmentally-friendly. It is of course a close cousin to compressed natural gas (cng), but Iveco is apparently not all that keen on running vehicles on cng in Britain. Why?

The biomethane supplied by Gasrec is of a consistent, high quality. However, the natural gas that comes out of the gas pipe varies from one part of the country to another. OK, you can put in driers to make sure that it’s OK — ending up with water in vehicle fuel systems has been an historic problem with cng — but when it comes down to it biomethane makes a better story because of where it comes from.

https://www.whatvan.co.uk/analysis-and- ... 2010/iveco

I get the idea Gasrec - the Biogas supplier - is using this point to justify purchase from them; but the variance, from what I've seen is real.

We'll see.

[LPGC]

Water contamination is mentioned but if the gas is dry are there chemical differences? Is Gasrec gas high quality because it is dry or because of the gas chemical composition?

We know there are chemical differences in petrol depending on the base oil from the well, refining and mixing with ethanol etc. Also with LPG it will be propane in the UK but may be a mix of propane and butane on the continent, small amounts of other LPG's in the mix in both cases.

There are plenty vagaries with an open loop system, even lots of vagaries for a closed loop and injection system to deal with but that's the point of a closed loop system... Temperatures (weather, intake air, fuel), humidity, barometric pressure, chemical differences in fuel, engine clearances changing with temperatures and wear and tare, even little aspects such as spring pressures and diaphragm tension. On any fuel could set up an open loop system using a lambda gauge but if any of the variables change the mixture is likely to change slightly, there's never a perfect setting for all conditions for an open loop system, only the best compromise setting to cover wide ranging conditions.

[CNG]

My classic is very much half-baked, its set-up helped by a O2 gauge. It works pretty well, but only within the limitations of the carburettor era. I won't credit it with more. An AEB Leonardo still sits collecting dust.

I would hope the closed-loop will cope with this, but Dai was talking about unhooking the Nevo's OBD after initial calibration. I'm sure there's variance between fills of LPG. I suspect NG's variance will be more marked.

Whilst both Biogas and NG are methane, the likes of Asda, Waitrose and Tesco are in this for green points, thus are using Gasrec's Biogas supplies. It's sourced from landfill, thus because it'd float away into the atmosphere anyway, comes greener than piped NG. As used in our homes, NG is piped-in from the North Sea, or from the Ruskies. Our North Sea flavour has a different calorific value to the other stuff. I understand, it can vary quite a bit.

I'm curious to know which TAP Dai has in mind, this car has a Denso ECU. When you give AEB's site component-selctor a whirl, AEB claim not to make one for its Bosch ECU sister? I'll give him a call and get it on order. Finally coming up the bulkhead with pipework, Nevo etc starts soon.

[disco stu]

Unless the AEB TAPs work different, I thought the only proviso on TAP choice was the type of crank and cam sensors used-hall or inductive

[LPGC]

Just wrote on another thread that I've been a bit lax for a couple of days in not being present on the forum, been particularly busy.

Interested in all your stuff @CNG. What do you reckon to CNG compressors for filling from piped home gas supplies and have/would you buy one? To fill a CNG car at home from piped gas supply how do you reckon vehicle fuel costs would compare to petrol?

There are more differences between TAP's than those you've mentioned, some are easily programmable, other not programmable at all, some can only be programmed using rare (always difficult to get hold of even when more commonly fitted but usually even more difficult now) specific TAP programming tools / interface cables/ software. The combination of crank and cam(s) sensor(s) can complicate matters on some vehicles like I've mentioned earlier.

[CNG]

Thanks for your advice on TAP matching LPGC. I've not been onto Dai as yet. That was my concern. A TAP is likely not required for most installs. Mine being rather obscure, there may not be such an animal to suit?

Interested in all your stuff @CNG. What do you reckon to CNG compressors for filling from piped home gas supplies and have/would you buy one? To fill a CNG car at home from piped gas supply how do you reckon vehicle fuel costs would compare to petrol?

This is a vast subject, which means the full answer is not only another thread, more another forum. It's akin to asking LPG blokes what happens from the filling-station back. If we get into the specifics of NG, one question leads to another, and it'll rail-road this conversion thread. I'll have a go in another thread.

The glib answer is that NG is cheaper, but with substantial upfront costs [read: price of a very decent used car/ cheap new one]. But that's hardly news is it? Alternative fuels will always suffer the same drawbacks. I first saw NG in use taking my lad to an ice-rink. Their Zambonis are usually NG, and some fork-lifts too, however that was nearer 20 years ago. The kit is extremely expensive, and I do this as much, 'because I can', as to save money. It's long-game, and works. For those prepared to see it this way, I'd tell anyone to take the plunge.

As i said, rather than rail-road this thread, we're better to see me cover this in a full thread...

[CNG]

First practical problem. I'm into the OBD wiring. Spoke to Dai, he confirms I read the Nevo schematic correctly, KME would have me tap the K-Line Pin 7 and L-line Pin 15.

Now I looked... Only I've looked long and hard on the back of the Volvo OBD plug, and there's no wire going to the L-Line. Pin 15 is empty. K-line Pin 7 is there. I would think I need the L-line, but with no L-line there, what happens?

I thought I had ISO 9141-2

[Gilbertd]

I would suggest forgetting about the OBD connection, leaving then both disconnected and calibrating it manually. OBD2 compliance didn't become mandatory in the EU until 2000 so I suspect your car is too old. It will have OBD to meet the US requirements which were needed from 1996, but not full OBD2.

[CNG]

Ah, thanks... maybe it reads well enough from one line? I'll see what Dai has on this, though he didn't mention it. I've done a bit of homework on this and it appears there's several flavours of OBD ISO 9141-2. Pin 15 is optional. This only leaves the question, does the Nevo ECU know that?

[CNG]

Good enough for me., Dai has it - Pin 15 Line L not required.

[CNG]

I've sent a list of queries to classicswede, and spoke to him to confirm wiring for the OBD lines. Now installed.
I freely admit that at this point I'm out of my comfort-zone. I know little of fuelling. I've less idea of how to select and config. the correct TAP. 10 days ago - I left Dai to ponder which TAP is required, and answer 4-5 queries, this with a request to send a base 'Nevo' configure file.

On top of correct fuelling, a TAP is an extra complication. Whilst a proper modern ECU seq.injection unit has potential to better the Necam factory installation, I don't think it'll be me 'on my own' that masters this. I know I'll struggle to even match the factory installation, let be improve on it. Without help, the variables are many, thus, be it fuelling or added ignition complications, I think a cock-up of one or both is next to inevitable.

I've had to let this conversion rest for a few days, life gets in the way, now back on it... I've two piles of parts here. A brand new KME Nevo kit on Dai's advice, or my stockpile of factory Necam parts. I'm at a fork in the road, and with no word from Dai, I don't want to go in 'blind'. I'm going with the pragmatic option, the devil I know.

Once I've got it running, ('if' I can get it running with stock Necam parts?] I will look to the Nevo install. That should give Dai aka classicswede more time to consider my queries, which TAP Dai suggests; the base 'Nevo' configure file, etc etc for a later date. Pix next.

[CNG]

Well this conversion hasn't taken the route I was expecting. I've been banging at it, on and off since the last post, and now it runs very well. It's been put back to factory-stock. Hence there's not much to say or show. The Necam system works well enough.
As I said, without proper guidance, I reckon it'd be slim-pickings for the chances of me getting the KME Nevo to run as well as the factory-fit, let alone better. There's too many variables without Pro advice. I'm not sure if I'm setting the bar too high, yet for me for all the extra work and expense it must match and then exceed factory-fit. I pushed him quite hard for info, yet I needed to get on - I've not heard from classicswede, or had any answers to my TAP and other queries. Now it runs, I've £300 in KME Nevo ECU here, the motivation to install the Nevo is reduced, so sorry to disappoint.

From my standpoint it's a success, I wanted this car to run gas and it does. Only, it's hardly likely to leave anyone in awe. As conversion threads go, this has become a non-event.

Sorry.

[CNG]

OK, I'm going to pick-up the task once more. I'll get on to Dai. What worries me is that maybe a TAP is not so easy with an ME7? Maybe there isn't one?
Is there much harm to be done, 'economy aside' from retarded sparks?

Standby.

[Gilbertd]

Burnt exhaust valves......

[CNG]

Ah, that'd make sense. Unburnt fuel must go somewhere.

[CNG]

I've found AEB's TAP selection bumpf, and page 25 indicates what I think I'm looking for. I've:


5 x coils … one per cylinder. No dizzy.
1 x camshaft sensor (I believe inductive but is it?)
1 x crankshaft sensor (I believe inductive but is it?)

But without understanding my sensor types I'm at a brick-wall.

I'd put the guide up for all, only forum won't allow PDF format.

Anyone?

TAP Selections 01.png (179.88 KiB) Viewed 2595 times

TAP Selections 02.png (171.97 KiB) Viewed 2595 times

TAP Selections 03.png (160.56 KiB) Viewed 2595 times

[CNG]

Shark.png (169.28 KiB) Viewed 2594 times

Cobra.png (134.72 KiB) Viewed 2594 times

Hard to get hold of, but if it's an AEB box we're after i think it comes down to a Cobra or a Shark.

[CNG]

I've not been able to get hold of classicswede and he's not answering email queries re: which TAP etc. hence, I've spent the day researching this, AEB's site is not easy to navigate and what information I can get contradicts. Pretty standard stuff for AEB!

But I think I have it. There's only one TAP available by anyone that'll read an inductive crank-sensor, sans half-effect camshaft, five pots, Denso ME7 etc. And that's a AEB Cobra AEB510N.

Seems the Cobra AEB510N is programmable. I'm not sure if AEB supply the AEB510N with software 'pre-flashed' for this set-up, I think not. Seems to be a 'jack of all trades', has various leads Types A to M? and program versions dependent on application. It requires a Type F lead AEB410-F.

I think we need variant: Software variant AEB510N-08. Best check-in with classicswede Dai, before I buy. I'm still having trouble raising him.

This TAP is not readily available, will need to be brought in from italy. We carry on...

[CNG]

OK, I've managed to speak to Dai classicswede. His TAP of choice is the Europegas EG Dynamic Timing Advance Processor. UK based stock is now non-existent, this was my fear. There's a Stag model around but I can only find stock in Poland. Delivery is 3 weeks at least on much of this stuff. Unless i find another route... I wait.

[LPGC]

Only stock in Poland? https://www.lpgshop.co.uk/stag-tap-03-1 ... processor/