Problems converting >06 BMW.. Help

[Gilbertd]

Is any of this relevant? In the original post he says "however when in sport mode and you give the car some welly the headup display sound and screen cut out for a second". So for some reason the installation of the LPG system, and the use of it at full bore, is affecting the cars Can bus driven head up display. He's never said that there is a problem with the LPG system.

[rossko]

We don't know, that's why we ask for more info. The OP is convinced the display issue is linked to high power on gas only. I can easily imagine any deficiencies in lpg delivery at high power causing the petrol ECU to panic, which in turn might disrupt other CAN connected systems.
Petrol : thinks - I'm too busy managing this disaster to respond to requests for data.
HUD : "Hello?"
HUD : "Hello?"
HUD : thinks - I am all alone in the world, I will reset now.

The linkage to LPG might only be imagined, but it does seem easy enough to test that.

There are other ways for the LPG to disrupt other systems, by drawing power or generating interference.

[pyro225]

Im back...ok so i should have said i had EMER rails with BiGas vaporiser... anyway i have now got BiGa everything and the same problem... except a little worse as the BiGas injectors don't hold on at the top so a little petrol is needed... any ideas?

Would the fact that it is not the OBD ecu be the problem have read that the more performance cars are giving out so much info the ecus needs it to run correctly?

[rossko]

We don't know what you had before, so no idea what 'biga' means either.
Same requests for facts as before are still outstanding.
We only know that your HUD blanks, but doesn't if you switch one bank to petrol. Presumably it blanks more often now?

[pyro225]

Sorry rossko that should have said BiGas.... The voltages and the gas pressures do not seem to fluctuate any more than usual at the problem area. the problem area has moved to a slightly different rev range with the new injectors. also i have managed to make the problem go away by idling on petrol and swithcing to petrol top end on the bigas equipment. my other problem though |(which i cant remember if i mentioned) is not fixed and not changed.... that problem is the idle.. it should idlee at 600rpm and if i reset the adaptions and run on petrol sure enough it does... however if i switch back to gas after a couple of runs its idling at 1000rpm...?

What else would you like to know? thanks again

[rossko]

Ah, I didn't twig it was Bigas, thought it was just "bigger"

the problem area has moved to a slightly different rev range with the new injectors.

Okay, probably poking in the right area then.

What model reducer(s) do you have now? What is the gas pressure set to when idling on gas? What happens to the pressure at your problem area, and just before?

What model injectors do you have now? What is the nozzle size you have used? What type do you have set in the software? What does the nozzle size guide in the software think about them?

What is the petrol injector time when idling properly on petrol? What is the petrol injector time when idling wrongly on gas?

What is the gas injector time as you approach and get into your problem area, at what RPM?

What non-zero values, if any, do you have in the "adjust carb" table?

[markocosic]

Where are your earth and battery feeds taken from?

Running 10 low impedance injectors is a lot of current and a lot of electrical noise, and it'll get worse at higher pulsewidths.

Many modern vehicles have "dirty" power and "clean" power buses. The HUD would be on the clean bus.

[pyro225]

Marko,

I believe you maybe in the right area, what do you think rossko...?

I am taking the live from my bonnet live jump point and ground from the ground jump point... a similar kit (Romano) was fitted to an M6 and had a similar issue, taking grounds and lives direct form the battery seemed to cure it? would that sound correct?

Regard to components still using the EMER vaporiser as it has a bigger output, and using the BiGas max i think they are called injectors (the biggest they do).

I have done some real digging today and looking at injection timing etc when the revs go high.. on petrol idle is smooth as expected.. switch to gas watching the timings and for 30 seconds say it is still fine then all of a sudden the injection timing starts going very low on one bank and the idle creeps right up? switching back to petrol after a minute or so sorts everything back out... anyone able to work out anything from this? i thought possibly putting an ecu with he obd link in might help as it can do on the fly fine tuning or is this irrelevant?

[pyro225]

i was also possibly going down the new valtek injector route ive heard they can hold on much better than most available
?

[rossko]

I have done some real digging today and looking at injection timing etc

Good .. now tell us the ruddy numbers ....

all of a sudden the injection timing starts going very low on one bank and the idle creeps right up?

Which timing (petrol or gas)? If the petrol is going down, does the gas actually follow it? I'm thinking your injectors may be bottomed out. What type of injectors have you told the software about?

Also consider cross-connected injectors, e.g. the gas is connected to petrol inj 1 and the corresponding gas injector is feeding cyl X instead. Potential crossovers can occur at the injector cut harnesses, the plugs to the main gas loom, the harnesses out to the gas injectors, the feeds from inj to manifold, the airways inside the manifold (Rover V8s are a favourite for that one)

[pyro225]

sorry mate, bank one is 2.5ms and bank two is 2.3.. but on gas it drops to 1.7 bank two that is...

I can look at the injector wiring but i have used the bmw dis software and looking at each individual injector time and the correct injector switches of the petrol and on the gas with no duplication?

[rossko]

Which is 1.7 ... gas or petrol ... I very much doubt your gas injectors are capable of 1.7mS, or that the ECU software will allow themn to go that low anyway.

Turn the gas pressure down, recalibrate, and see if your idle stabilises.

[pyro225]

sorry that was the petrol reading when on gas... and gas was about one above it...

[rossko]

Y'know ... going back a bit we never heard how many reducers you actually have, its pages of blood-out-of-stone here. So far as I can understand, you have one 380hp reducer on a 500hp engine and are wondering why it goes wrong at full tilt.

By using fat injectors in an effort to overcome top end limitations, they're too fat to be controllable at idle loads. Hence my suggestion to reduce gas pressure to see if idle improves.

[pyro225]

Hi rossko tried running at between 1.2 and 1.5 and also tried idle and gas to 6k rpm and idle petrol and gas top end ... the first seemed to run the best however the idle was the issue and it was sporadic as said...

[pyro225]

This is a theoretical question... But possibly considering running 2x king 5cyl ecus and the new valtek injectors similar to the prins ones which hold on a lot better my question is can you have both plugged into the obd socket for the live monitoring or only one ?

[rossko]

Hi rossko tried running at between 1.2 and 1.5 and also tried idle and gas to 6k rpm and idle petrol and gas top end ... the first seemed to run the best however the idle was the issue and it was sporadic as said...

I'm sorry, I really don't understand what any of that means.

What are the gas injector times at idle, when you have the idle problems?
For an experiment, set the pressure to 1.0 bar and recalibrate. It will be pants at top end, but does it help your idle problem? What are the gas injector times at idle, after you have done that?
How many reducers do you have fitted, what model? If you have twins or siamesed units, how careful are you being about pressure adjustments? When is Christmas coming? How many secrets can you keep?

can you have both plugged into the obd socket for the live monitoring or only one ?

They will fight, you can't do it. OBD capability will not, cannot, fix incorrect injector sizing or gas pressure or basic setup issues.
Are you really going to throw away what you have already and buy yet more gear without investigating the issues properly?

[pyro225]

Rossko thanks for your help...basically after I read your last post I managed to find someone else who had the same problem with the same ecu... I believe the 10cyl ones are quite old now, and he cured it by keeping everything the same and changing the ecus for 2x romans 6cyl ones. he also stopped getting the signal from the coil which is not possible with the 10cyl kit. As I previously said I had one king ecu kicking about so I though id try one bank see how it went... it went well... so I did the other and while I had the tops off I swapped back to the bigger EMER rails I had from the original conversion (can handle 500cc each it hink that's how you measure) There is some fantastic news in that my idle is spot on now and it does not cut the HUD out... but theres a but...

Ive not got this far before, my car has two fuel maps (BMW factory fitted with m button) one for 400bhp and one for 500bhp and when I swap them with the button it buggers it all up.. I have checked and the petrol timings are completely different? the annoying thing is it warms up on 400 so I need it on that one...

Would you expect this?

My options as I can see are as follows... buy another 2 ecus and run a switch when map switching (not ideal)

Or get car coded to run just 500bhp map... what do you think?

[rossko]

I've no idea. Are we still wondering why the 500bhp mode struggles with a 380bhp vaporiser?

[pyro225]

Sorry I didn't answer that I have two T'd together so that shouldn't be the issue and as I said the rails should be good but do you think two completely different maps are workable with my setup?