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[tigers_gonads]

Lpg has been throwing up a low voltage warning over the past few months.

Turned out that the alternator regulator was dying (down to 13.4 volts after it had warmed up) so I replaced the regulator and cleaned all crimps / terminals on the battery / alternator end.
Now got a steady 14.2 volts (no load / engine running) and 13.98 with everything switched on that uses volts.

Took the shed off for a run to fill up with gas.
Turned the gas on and streight away it cut out with a low voltage warning again 
After driving around for 10 minutes, I tried again and this time it held and the lpg cut in.

Got home and cleared 19 low voltage codes with the stag software and decieded to have a quick nosey at the petrol / gas map.
Right, the petrol (blue) calibration map is still on the screen but the lpg (green) line has shrunk to half its size and is all over the place.
The car battery was removed for about 5 hours so both ecu's would have been powered down.

Anybody got a clue what has happened to the gas map ?
Can I reload one that is stored on my laptop ?
If thats whats needed, how ?

Iirc these lpg problems started after the tank blowoff valve went when the tank was full on a bloody hot day / the next day, the car had a very hard run back from stoke (don't ask how fast  )

Hope that lot makes sence too somebody because its doing my head in now 

[TheBoy]

I think you need to understand why the Stag ECU is reporting low voltage, as a first port of call.  Is the battery on its way out - is the code appearing when starting the car, etc?

[tigers_gonads]

The battery seems ok to me.
Always holds a good 12.5 volts on a cold morning.
Never drops below 10 volts when cranking from cold and turns over pretty fast / fires first turn of the key.
Code appears after the car has started.

I have found that if I start the car first thing in the morning and leave it to idle for 5 minutes before I switch on any loads then switch the lpg on manually, it holds first time and drives away without a problem.
If I leave the lpg in auto (temp set too 35 degree's iirc) then it tends to throw a wobbly 

About this voltage warning ............... does it trigger a fault if the supply voltage drops too low or could it be any another part of the system I.E injectors / or even (thinking back the the blowoff valve) a component in the tank / solinoid / valve that may have been damaged by the valve letting go ?
Put it this way, when it went pop, I had half the street running outside because they thought a car had blown up or something      Me, I just kept away from the windows until they had all pished off 

[tigers_gonads]

The battery seems ok to me.
Always holds a good 12.5 volts on a cold morning.
Never drops below 10 volts when cranking from cold and turns over pretty fast / fires first turn of the key.
Code appears after the car has started.

I have found that if I start the car first thing in the morning and leave it to idle for 5 minutes before I switch on any loads then switch the lpg on manually, it holds first time and drives away without a problem.
If I leave the lpg in auto (temp set too 35 degree's iirc) then it tends to throw a wobbly 

About this voltage warning ............... does it trigger a fault if the supply voltage drops too low or could it be any another part of the system I.E injectors / or even (thinking back the the blowoff valve) a component in the tank / solinoid / valve that may have been damaged by the valve letting go ?Put it this way, when it went pop, I had half the street running outside because they thought a car had blown up or something      Me, I just kept away from the windows until they had all pished off 

Can anybody who understands the dark art of lpg kits shine any light on this bit please 

[Kevin Wood]

I can't see how a low voltage warning can be related to the relief valve. I think this is the wrong tree to bark up.

I think my next attack would be to check the charging, as you should have 14 volts+ across the battery.

During my lack of leccy recently, the LPG system outlasted pretty much everything else in the car, so I'd be checking the supply wiring to the LPG system too, along with all the usual suspects such as crimping of the battery terminals and the alternator output.

Look at the live data from the LPG ECU, as this reports the battery voltage the ECU is actually seeing.

[tigers_gonads]

I can't see how a low voltage warning can be related to the relief valve. I think this is the wrong tree to bark up.

I think my next attack would be to check the charging, as you should have 14 volts+ across the battery.

During my lack of leccy recently, the LPG system outlasted pretty much everything else in the car, so I'd be checking the supply wiring to the LPG system too, along with all the usual suspects such as crimping of the battery terminals and the alternator output.

Look at the live data from the LPG ECU, as this reports the battery voltage the ECU is actually seeing.

The relief valve (shall we say) was pishing in the dark tbh.  Everything seemed to start to go tits up after the valve went pop and the next day after a very quick 140 mile ish run back from Daz's 

The old regulator started out with a nice 14.3 volts when cold but soon dropped off too a max of 13.2 after a good thrash  run to let the bits and pieces warm up.
Since I changed the regulator, I get a steady 14.2 (at the battery) wether the bits and bobs are hot or cold.

All terminals was checked / cleaned and greased when I put it all back together

I don't remember what voltage the stag ecu was recording 
I'll plug the lappy in tomorrow when I get back from work 

[tigers_gonads]

Update on voltages.

Engine warm  Idle at 750 rpm

Voltage at battery (positive on terminal / negative on engine)     14.3 volts

Stag software reading the voltage at 14.1 volts with lpg injectors running

Cleared 3 "volage errors" from stag software in the last 2 days .

[Kevin Wood]

No problem with battery voltage then. Does the stag ECU report a decent voltage? Could be supply wiring to the Stag. Or the code might not be referring to supply voltage. Is "Voltage error" all the error message says?

[tigers_gonads]

I've got a 0.1 volt drop between the battery and the stag ecu (readings taken from the stag software on the laptop) at idle on petrol.

Down to 0.3 volts drop with the lpg injectors running.

That looks ok to me 

[sassanach]

one of your injectors is fubared!!.had exactly the same messaqe on my caddy  when i was running valteks,dumped them,fitted "magics" problem has not re-occured. .

[tigers_gonads]

one of your injectors is fubared!!.had exactly the same messaqe on my caddy  when i was running valteks,dumped them,fitted "magics" problem has not re-occured. .

Now thats a thought.

I've been getting a smell of gas from under the bonnet but couldn't track the bugger down 

Does anybody know the internal resistance of the gray injector blocks that have been supplied with the kits we recieve from Tielo ?

[Mrs Cakey]

Check the voltage drop when cranking too

[Mrs Cakey]

one of your injectors is fubared!!.had exactly the same messaqe on my caddy  when i was running valteks,dumped them,fitted "magics" problem has not re-occured. .

Now thats a thought.

I've been getting a smell of gas from under the bonnet but couldn't track the bugger down 

Does anybody know the internal resistance of the gray injector blocks that have been supplied with the kits we recieve from Tielo ?

I'd guess at 3 ohm. It's marked on the coil somewhere

Oh, and I can't see that being the cause of the gas smell

[albitz]

Have you been reading his text books while he has been spending his time whizzing up & down the A12 ? 

[Mrs Cakey]

Have you been reading his text books while he has been spending his time whizzing up & down the A12 ? 

No. He stole my laptop while I wasn't looking! I'll make sure I log out next time