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[Taxi_Driver]

When you find a fault and fixing it makes the problem worse  

VeccyC turned up today with running probs on lpg.....ie will run for a bit on lpg then switches to petrol.

Emissions light is on all the time too.

So off to my local friendly garage who has a 'snap on' scanner that can read CAN bus to read the codes

It had a few various ones stored including P0100 Maf sensor.
Cleared the codes and started her up......rev'd it bit on petrol.....checked the codes and nothing stored.
Switched to lpg and again rev it again....when the revs dropped it stalled after a missing for a bit.

Checked the codes and P0100 maf sensor has come back.

So I decide to check for an air leak....pop the bonnet and if you listened carefully you could hear a slight hiss.....anyway I found the leaky pipe.....it was a vac pipe connecting to a soleniod for the lpg system....and the same pipe also goes to the evapourator for the lpg......so I thought id cracked it....leaking vac no wonder its having problems. The pipe had been resting on the steering rack and you could see where it had worn through.
So I cut out about an inch of damaged pipe and joined them back together with a straight thro' pipe connector.

Now it wont run on lpg at all  

As soon as it tries to switch it coughs and its back to petrol again  

The engine ecu isnt storing any codes anymore......so that leaky vac line seems to have been causing the maf sensor error also emissions light isnt on anymore.

So at this point I given up with up and its booked into vx dealer in Bath on thursday.......im hoping that the pressures for the lpg are now miles out and it will just need adjusting.

Tho on the upside.....the vx dealer isnt going to tell me the maf sensor is fubared and needs changing  

Oh and I discovered summat else that might interest TB and his tractor.
I was playing with the scanner in live data mode.....the temp guage was sat at 90C midway point for it.....ecu water temp was saying 95C......so the ecu seems to read 5C higher than the guage like it does on his tractor.

[tunnie]

it seams that all gauges seam to read low, next time the 2.2 is around there might get a live feed on that see if it reads low too.

Thats a bugger about the vac pipe, odd now its not running at all. How about taking the pipe connector off, do a bodge join (gaffer tape or something), It will run like a sack of spuds on LPG, if it does at-all,  be interesting to see what it does.....

[Taxi_Driver]

it seams that all gauges seam to read low, next time the 2.2 is around there might get a live feed on that see if it reads low too.

Thats a bugger about the vac pipe, odd now its not running at all. How about taking the pipe connector off, do a bodge join (gaffer tape or something), It will run like a sack of spuds on LPG, if it does at-all,  be interesting to see what it does.....

I think that vac pipe does a couple of jobs Tunnie....one it goes to a soleniod with 3 wires coming off it.....i suspect these go to a lpg cut off valve......ie no vacuum, engines not running so shut the lpg supply off. two it goes to the evapourator.....i think this is so the evapourator knows how much lpg to fire through. Certainly a while ago i discovered you could unplug the vac from the evapourator and as long as you kept the revs up it would carry on running on lpg.....let the revs drop and the lpg rail (i think) overpressurises and it switches back to Petrol.

Martin will be able to confirm or put me right there.

It may have had a slight leak when the vx dealer fitted a new evapourator and adjusted the pressure about six months ago....thats why im hoping its just the pressure miles off now.
Or even if they do say its the evapourator faulty......i'll just ask for a new one under warranty please....as this one is only about 6 months old......you check....you fitted it  

[Martin_1962]

Usually vacuum goes to

Evaporator and pressure sensor.

Anything else on that line?

[Martin_1962]

I think that vac pipe does a couple of jobs Tunnie....one it goes to a soleniod with 3 wires coming off it.....i suspect these go to a lpg cut off valve......ie no vacuum, engines not running so shut the lpg supply off. two it goes to the evapourator.....i think this is so the evapourator knows how much lpg to fire through. Certainly a while ago i discovered you could unplug the vac from the evapourator and as long as you kept the revs up it would carry on running on lpg.....let the revs drop and the lpg rail (i think) overpressurises and it switches back to Petrol.

As m,y previous and that behaviour I had with a split breather

[Taxi_Driver]

Usually vacuum goes to

Evaporator and pressure sensor.

Anything else on that line?

Just goes to/comes from throttle body

[TheBoy]

Oh and I discovered summat else that might interest TB and his tractor.
I was playing with the scanner in live data mode.....the temp guage was sat at 90C midway point for it.....ecu water temp was saying 95C......so the ecu seems to read 5C higher than the guage like it does on his tractor.

Yes, it seems all prefacelifts read high up to midpoint, and under above midpoint, with midpoint itself covering a wide range...

[Taxi_Driver]

Oh and I discovered summat else that might interest TB and his tractor.
I was playing with the scanner in live data mode.....the temp guage was sat at 90C midway point for it.....ecu water temp was saying 95C......so the ecu seems to read 5C higher than the guage like it does on his tractor.

Yes, it seems all prefacelifts read high up to midpoint, and under above midpoint, with midpoint itself covering a wide range...

This was on my veccyC.....i watched the live data for a bit on the ecu water temp.....it crept to 97C on the scanner (bout 92C on guage).....then cooling fan came on slow mode....took it down to 92 on scanner (bout 87 on guage) then fan turned off and repeated

[TheBoy]

Oh and I discovered summat else that might interest TB and his tractor.
I was playing with the scanner in live data mode.....the temp guage was sat at 90C midway point for it.....ecu water temp was saying 95C......so the ecu seems to read 5C higher than the guage like it does on his tractor.

Yes, it seems all prefacelifts read high up to midpoint, and under above midpoint, with midpoint itself covering a wide range...

This was on my veccyC.....i watched the live data for a bit on the ecu water temp.....it crept to 97C on the scanner (bout 92C on guage).....then cooling fan came on slow mode....took it down to 92 on scanner (bout 87 on guage) then fan turned off and repeated

I suspect it is the same on all gauges, but I have only fully tested on my own 2 Omegas...

[Taxi_Driver]

On a different note i noticed the charging voltage on the veccyC was 13.6v according to the scanner.....on idle and revving it....i thought this was a tad low.....was expecting to see around 14.2v.....tho i guess this is within tolerance.

Seeing live data can be a dangerous thing  

[TheBoy]

On a different note i noticed the charging voltage on the veccyC was 13.6v according to the scanner.....on idle and revving it....i thought this was a tad low.....was expecting to see around 14.2v.....tho i guess this is within tolerance.

Seeing live data can be a dangerous thing  

ignore ecu's view on battery voltage and use a meter

[Taxi_Driver]

On a different note i noticed the charging voltage on the veccyC was 13.6v according to the scanner.....on idle and revving it....i thought this was a tad low.....was expecting to see around 14.2v.....tho i guess this is within tolerance.

Seeing live data can be a dangerous thing  

ignore ecu's view on battery voltage and use a meter

oh dear....that means getting my Fluke MM out.....and we know Marks opinion on them  

[TheBoy]

On a different note i noticed the charging voltage on the veccyC was 13.6v according to the scanner.....on idle and revving it....i thought this was a tad low.....was expecting to see around 14.2v.....tho i guess this is within tolerance.

Seeing live data can be a dangerous thing  

ignore ecu's view on battery voltage and use a meter

oh dear....that means getting my Fluke MM out.....and we know Marks opinion on them  

Fluke, whilst robust and accurate, are overpriced and not particularly reliable....

[The Barge Captain]

Fluke, whilst robust and accurate, are overpriced and not particularly reliable

Work a treat though if you never paid for the thing in the first place.

[Taxi_Driver]

Fluke, whilst robust and accurate, are overpriced and not particularly reliable

Work a treat though if you never paid for the thing in the first place.

Very true