Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[megaomega123]

LPG started running lumpy about a week ago. I presumed it to be the filter needing changed. I did this today and still running bad.
Plugged into laptop to check settings and the following happens.

Keep getting disconected with error: no lpg controller.
Updated controller with no change.
The software also shows my rpm as 4200 when idling at 600 thus was switching to petrol at 2500rpm due to the threshold.

Eveything is dandy on petrol although the rpm is still incorrect.
Also my injectors have become very ticky, you can hear them a mile away.
Any help appreciated as cant afford petrol  
EDIT* Also to add that I have had EML occassionally with code for incorrect rpm signal!

[Kevin Wood]

LPG started running lumpy about a week ago. I presumed it to be the filter needing changed. I did this today and still running bad.
Plugged into laptop to check settings and the following happens.

Keep getting disconected with error: no lpg controller.
Updated controller with no change.
The software also shows my rpm as 4200 when idling at 600 thus was switching to petrol at 2500rpm due to the threshold.

Eveything is dandy on petrol although the rpm is still incorrect.
Also my injectors have become very ticky, you can hear them a mile away.
Any help appreciated as cant afford petrol  
EDIT* Also to add that I have had EML occassionally with code for incorrect rpm signal!

Do you mean you have updated the firmware in the controller?   If so, it has likely lost all its' calibration information (number of cylinders, for a start, giving an incorrect RPM reading). I would start by making sure everything on the first screen is configured correctly for your engine. Be VERY careful of the configuration of the gas injectors as you can burn them out if they are incorrectly set. Yours are Valtek, 1 OHM.

Changing the firmware has introduced an unknown that you could have done without, TBH.

Kevin

[megaomega123]

TBH updating the controller had no effect on anything. All the settings on screen one are as they were. 6 cylinder and the 1 ohm injectors.

It seemed to happen all of a sudden then got progressively worse, which is why I thought filter. I think the laptop and serial to usb adapter may be the connection issue but as for the actual running, none of the settings have been changed to effect it. This is the 1st time since the problem began that it has been plugged in.
I cant understand how the software, even before update, was reading 4200rpm at idle on both gas and petrol.
Could it be the crankshaft sensor at fault and that the gas is more sensitive to it or is that a silly idea?

[Kevin Wood]

Could it be the crankshaft sensor at fault and that the gas is more sensitive to it or is that a silly idea?

Nope. Not a silly idea at all. A quick paperclip test will tell you if you have a crank sensor issue.

Is the LPG RPM indication stable or all over the place?

Kevin

[megaomega123]

RPM is stable but reading at almost x10  600rpm is coming out at 4200

I have done paperclip before and always comes back with incorrect rpm signal. Cant remember the code. I am working tonight but have all day tomorrow to tinker and will get an alternative laptop too.

I don't want to be chucking money at unneccasary parts so your help is very much appreciated.  

[Kevin Wood]

LPG system is using the same RPM signal as your tachometer so something is amiss there but a duff crank sensor needs sorting anyway. If you're getting a code 19 it points to a duff crank sensor.

Kevin

[Lazydocker]

LPG system is using the same RPM signal as your tachometer so something is amiss there but a duff crank sensor needs sorting anyway. If you're getting a code 19 it points to a duff crank sensor.

Kevin

Agreed... But the LPG issue could be as simple as a loose connection or faulty setting. Check the codes before doing anything else!

Just out of interest... When were the plugs last changed?

[megaomega123]

Plugs are around 20000 miles in.
It was code 19 that I was getting but I got an eml flash yesterday on gas so will check it again once I wake up properly.
It takes a longer turn of the key to get started these days but runs perfect on petrol.
It feels like a misfire on gas.
Going to connect it to a different laptop today and read eml codes so will post back results.
How much is a crankshaft sensor from vauxhall? What is the part number?
I presume it is this one
http://cgi.ebay.co.uk/CRANK-SHAFT-SENSOR-VAUXHALL-OMEGA-1994-2004_W0QQitemZ270340457644QQcmdZViewItemQQptZUK_CarsParts_Vehicles_CarParts_SM?hash=item270340457644&_trksid=p3286.c0.m14&_trkparms=72%3A1683%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318

Thanks for the help  

[Kevin Wood]

Difficult starting is a classic crank sensor symptom. Replace it before it leaves you standing.

There are several types of connector on the sensors. Best to find the connector (behind passenger side cylinder head) and confirm type before ordering one.

Kevin

[megaomega123]

Managed to paper clip it again and getting code 19

Tried an xp laptop and stayed connected to auto calibrate. Same problem exists and an over reading of rpm.

I think it is time for the crank sensor. Oh well its not bad, 134000 on the original    I'll get back once this has been changed and conclude if this is the problem with the gas also.

Many thanks for your help.

[Kevin Wood]

I wouldn't have auto-calibrated the LPG with a problem present - because it will now have made a mess of the settings that used to work OK before the crank sensor packed up.

Change the crank sensor and verify that it's driving OK on petrol, then revisit the LPG system if it hasn't already resolved that problem too.

Kevin

[megaomega123]

Put a tenner of gas in today and did a 30 mile trip. Car pulled well. The only issue seems to be under 3000rpm and idle which are hesitant and lumpy respectively.
As it runs perfect on petrol, could it be an injector issue as opposed to the crankshaft sensor. I am changing the crankshaft sensor anyway but think there may be a coincidental lpg problem.
An example of the hesitancy is 4th gear 3000rpm then foot down, you can feel a sort of engine braking followed by a surge of power then repeated.
Idle feels like oil in plug wells - which there isn't.

Any clues from that??  

[Lazydocker]

Hmmm... If it did it on petrol too I'd have said it was an air/vacuum leak but just on LPG seems strange :-/ :-/

It's the over-reading that doesn't make sense, unless the RPM pickup is set incorrectly

[megaomega123]

Hmmm... If it did it on petrol too I'd have said it was an air/vacuum leak but just on LPG seems strange :-/ :-/

It's the over-reading that doesn't make sense, unless the RPM pickup is set incorrectly

It is strange considering it has always read it perfectly then all of a sudden reads it at 8 fold  

[Lazydocker]

Hmmm... If it did it on petrol too I'd have said it was an air/vacuum leak but just on LPG seems strange :-/ :-/

It's the over-reading that doesn't make sense, unless the RPM pickup is set incorrectly

It is strange considering it has always read it perfectly then all of a sudden reads it at 8 fold  

Have you accidentally changed any settings?

Any work been done recently which may have disturbed the wiring?