romano risN on p38

[matcossy]

hi chaps it seems I have develop a running problem with the gas, on petrol its 100% but on the gas it has started lack power if I get it to to 50ish it juddus and I have to give more throttle and in the morning it seems not to want to run atall till its fully warm,,

any help wold be great

best regards matt,, derby

[LPGC]

The juddering will most likely be misfiring. There are many faults that could cause misfiring...

Of the car itself (so not really an LPG system problem) the cause could be, for example, ignition system related (spark plugs / leads / coil packs etc), lambda probes, air flow meter... These faults would be the fault of the vehicle, not the LPG system, but can cause the spark at the spark plug not to be strong enough to ignite the air/LPG mixture or for the air/LPG mixture to be too rich. Both these types of problem can cause a misfire when running on gas which doesn't occur when running on petrol.

Then there are LPG system problems, such as worn LPG injectors, broken sensors (temperature or pressure), broken reducer(s), bad calibration.

Difficult to diagnose this type of problem remotely - Would advice to make sure the spark plugs are all in good order (which could cure your problem), then maybe take it to a reputable LPG specialist. I'm about 50 miles from you if you're in Derby.. And would definitely be able to sort it.

Simon

[matcossy]

hi thanks for the reply,

I did replace the ht leads and plugs in august when I did a oil change,,

I was thinking maybe its the injectors as on idle if I bring the revs up to 1000 rpm it vibrates but on petrol it don't,,,

yes I am in derby I don't mined traveling to get this sorted.

best regards matt

[Gilbertd]

If it was injectors it would be more likely that it would be rough at idle but smooth out as you bought the revs up. It does sound more like a misfire though, not that easy to notice when 7/8ths of the engine is working as it should. Bear in mind that as the LPG system is slaved off the petrol system, it could be something affecting that. It could be running rich which would cause a random misfire and as LPG needs the mixture to be closer to optimum then it might not be far enough out on petrol to show itself. Has it started using more fuel than before recently?

[LPGC]

All true comments, let me know if you'd like me to have a look. I keep all parts in stock, hopefully they won't be needed.

Simon

[matcossy]

well this morning on the way to work it finely started to opperate normaly (this is when its fully hot engine) although when I gave it full throttle it witched back to petrol with warning from gas gauge,,

I have notice this hole problem started on the same day I fill up at the local asda mayby just coincidence ,

one other thing is the switch over lights have not all been working correctly but tonight its telling me I have a full tank but I no it should have about half a tank,,


best regards matt

[matcossy]

lpgc are you open saterdays??

regards matt

[LPGC]

Sunday would be better than Saturday, as I have my daughter this Sat until 430pm..

Fancy coming Sunday?

Simon

[Gilbertd]

Sounds like it could be a bad earth and power to the solenoids is coming back on the level gauge signal wire. I'm sure Simon will sort it though.

[matcossy]

simon sunday is good for me what sort of time is good for you??

whats your address?? if you prefer you can text it me,,

just been out in the range rover and the switch is still saying full so as soon as I got home I look on the tank and the gauge in there says 60 so around half a tank as I thought could the switch cures these problems???


regards matt

[LPGC]

Hi Matt,

Sunday at 10am or 11am any good?

My address is on my website (http://www.Lpgc.co.uk), website link is at the bottom of all my posts! Anyway, it's Mill lane, South Elmsall, WF92DS.

Simon

[matcossy]

ill try to get there as close to 10 as I can I really hope you can get to the bottom of tis problem,


if I text you sunday I set of you shpuld when to expect me

regards matt

[matcossy]

I just had a look at my earth for the tank and found its got 12v I take it the soleloid or the sender is faulty do you keep them in stock???

regards matt

[rossko]

If the eartrh wire is not at earth voltage, it is probably not connected to earth i.e. suggests a fault in the wiring to the front (common winter complaint - road salt corrodes the copper if the wire is nicked)
You do have to think about where to put the other probe of the meter when trying to measure earth - do not assume the tank itself is earthed very well.

[matcossy]

I put the red probe on the earth wire and the black probe on a chassie earth,

iv left it of and now the change over/fuel gauge seems to be working correctly

its really bugging me now

[Gilbertd]

By poking around with a meter it sounds like you've remade the dodgy connection.

[LPGC]

I've got them in stock but like Rosko and Gilbert others say, seems more of a solenoid earth problem.

Simon

[matcossy]

simon im sure you will get to the bottom of it,

would you wont me to come with a full 1/2 or 1/4 tank of gas?

matt

[LPGC]

Thanks Matt, I'm confident of sorting all your LPG problems!

1/4 or 1/2 a tank won't make much difference, though maybe 1/2 tank will be better as this will guarantee that fuel slosh won't effect any heavy throttle use during test drive(s). Removal of the fuel level electrical sender doesn't need the tank to be empty as this wouldn't mean leaving a hole in the tank! I doubt the sender will need replacing but it's (maybe common with the tank solenoid) earth may need sorting out as already advised by others. Depending on how we find the gauge has been wired (some wiring configurations could mean that the sender has been exposed to having 12v placed directly across it).. we may need to remove the sender to check that it always sends a voltage proportional to the level of fuel measured by the tank float - If a sender is exposed to having 12v directly across it (as can effectively be the case if there is a fault with some wiring configurations) some types of sender can be burned out only in the position they were pointing to at the time of the burn out. In which case a gauge can seem to work normally for most of it's range, but will usually show full in the position it was burned out. I expect issues associated with any bad earth and with the gauge to be easy fix(es).

Perhaps more to the point, would expect to spend more of the time looking into the cutting back to petrol when you put your foot down and juddering issues you've mentioned... unlikely much to do with the gauge problem.

Looking forward to meeting you and sorting this Matt,

Regards,

Simon

[matcossy]

ok I have got new plugs and change over switch, but it seems that I have lost 2pots after only 3days running on the new plugs I have plug the lead from the next plug to see if it is the injector or an electrical pro it did not move to the next injector when it did this so I think the injector is tost

I can not fined these injectors any where so what brand can replace them with??

matt