Cyl 2 misfire and running lean

johnny_e · Jun 11th, 2009, 10:55

My V40 is a yr 2000 phase 2 1.8 and has an OMVL Dream sequential system fitted about a year ago. It runs really well except that on a very light throttle, I get the engine light coming on - maybe just once a day. It mostly happens on a flat throttle with no acceleration.

It was mostly getting 302 errors on cyl 2 but I just changed the plugs yesterday (to NGK Irridium LPG ones) and thats gone (for now). Just getting a 171 lean error today. Again, on a light throttle. Temp sensor was replaced last week as the gas ecu was reading far too cold relative to the water temp.

My installer has had the car in countless times to try and resolve this. My own conclusion, OMVL is crap. Any other installers near me wont touch it which speaks volumes. I'd love a 2nd opinion, but just cant get one.

I'm on the original coil packs and leads. The car has 56k miles on it, 36k of which were on petrol.

So, before I ditch my much loved and perfect condition V40 - has anyone got any ideas? If it werent for this light coming on now and again, I'd be oblivious. Just concerned that I'm damaging the engine. The car is mint in every way - tight as a nut and I want to put another 100k on it - but am worried that this OMVL system will cause a big failure some day.

Johnny

[edit: should say, the car is flawless on petrol. No OBD errors at all - and I tested it for a whole week on petrol. swopped coil packs a while back, misfire stayed on cyl 2]

davew · Jun 11th, 2009, 11:56

Could it be the lpg injector on number 2? Or any associated hoses?

This would cause a miss and running lean on that cyclinder...

johnny_e · Jun 11th, 2009, 12:11

Quote:

Originally Posted by davew

Could it be the lpg injector on number 2? Or any associated hoses?

This would cause a miss and running lean on that cyclinder...

Well... I think I've eliminated that. Maybe you could correct me - I took the rail apart last week and swopped the solenoid/spring/o ring from cyl 2 onto cyl 1. Heres it stripped:

But did I actually swop the injectors? Or are they in behind here:

All injectors run fairly silently and have about 20k on them. Hoses all seem fine. Firmly clamped in place and no evidence of leaks at the point of being tapped in.

davew · Jun 11th, 2009, 12:25

I am not familular with your setup, but if it looks anything like mine then your injectors will be on the other end of the 4 pipes going up in the picture.

Is there anyway you can test that gas is actually coming out of number 2?

Everything may be working as it should but the gas just not getting there.

Maybe a blockage in the pipe. Could you swop everything over that is soley for injector 2 for injector 1?

johnny_e · Jun 11th, 2009, 12:40

Those 4 pipes you see are about 6 inches long and are tapped into the inlet manifold. So am i right to say that the actual injector nozzles are what's tapped into the inlet then?

I am so frustrated as I've had it back to the installer well over half a dozen times. The misfire isnt there now I've put the new plugs in, but it gave a 171 yesterday. I have a feeling that a 302 will be back in due course...

Once again I live in the wrong place (NI). If I was on the mainland I'd be able to bring it to an expert for a 2nd opinion. Anyone else here has steered clear of OMVL and cant help me. Thing is... I cant sell the car while this is happening either - so its catch 22.

peter8315 · Jun 11th, 2009, 15:26

Hi, you say it was fitted about a year ago, if its still under garantee i would take it back and leave it with them until its put right, i think thats your only option, as they should be the experts on this system, regards, Pete.

johnny_e · Jun 11th, 2009, 15:31

Yes.. and no...Pete. The system was bought in 2006 for my Vauxhall at that time. I sold that and had the system transplanted to the Volvo - using an OE S/V40 tank, new plumbing, exchange rail etc. So, the likes of the ECU is 3 years old - whilst other parts are a year old. In fairness to the fitter, its been back 6+ times and he tries... but he's too quick to turn to the laptop and say that the new systems from OMVL have a slower pulse for low throttle. I'd really need someone else to look at it properly without bias. But that aint happening. I emailed FES who import OMVL kit in the UK - to see if anyone else in NI does OMVL - but I suspect thats a dead end.

Do you think that continual errors such as this (albeit just happening once a day for that split second) will end in an early death of my engine? Thats what I fear - and thats whats going to mean me trading the car in. Unfortunately I aint got a fortune to spend, so will end up in a soul-less tdci. Great! (At least I've got my old Audi Coupe V6 tucked away for the weekends!)

Vallhund · Jun 15th, 2009, 19:14

I got a misfire on cylinder three but only after i fitted the 'Flashlube' kit. Found that i had put the feed pipe to the Brake vacumm hose and was just running along the wall of the pipes and ending up in that cylinder. Had to drill a hole after the butterfly valve , thread it and insert the brass tube directly in the flow of the incomming mix. Got rid of the misfire. It was the only spark plug (normal plug) that was wet and it smelled the same as the Flash lube. Have , like you , also changed to Irridiums. 240 Torslanda.

petrolhead69 · Sep 17th, 2009, 21:02

OMVL kit is usually pretty good quality, certainly better than bedini, romano and BRC IMO but positioning of the injector nozzles in the manifold is critical, it might be an idea to try some short copper or brass spuds to get the point of lpg entry closer to the inlet valve then remap. I had similar problems with a rav4 and that made a huge difference, in the end it ran better on lpg than petrol. has your installer tried flashing the gas ecu with the different firmware versions? there are different versions that use different methods of calibration and mapping that make quite a difference. Nick at FES knows his stuff, but I think he only provides tech support to installers who buy from him but if he only has 1 installer in NI and is giving a bad rep to omvl in the area he might be keen to help. are the plugs OK? i would change at least the plugs just to be sure. HT components that work perfectly fine on petrol can cause running problems on gas as lpg/air mix has at least 25% higher electrical resistance than petrol/air mix. a gentle misfire can throw the o2 sensor readings out without actually spluttering.
Also check for an air leak near the lpg nozzle or a leaking petrol injector O ring
good luck

petrolhead69 · Sep 17th, 2009, 21:04

sorry, i missed you changed the plugs, too much cobra beer;-)

Jun 11th, 2009, 10:55	#1
johnny_e Junior Member Last Online: Oct 4th, 2009 10:39 Join Date: Jul 2007 Location: County Armagh	Cyl 2 misfire and running lean My V40 is a yr 2000 phase 2 1.8 and has an OMVL Dream sequential system fitted about a year ago. It runs really well except that on a very light throttle, I get the engine light coming on - maybe just once a day. It mostly happens on a flat throttle with no acceleration. It was mostly getting 302 errors on cyl 2 but I just changed the plugs yesterday (to NGK Irridium LPG ones) and thats gone (for now). Just getting a 171 lean error today. Again, on a light throttle. Temp sensor was replaced last week as the gas ecu was reading far too cold relative to the water temp. My installer has had the car in countless times to try and resolve this. My own conclusion, OMVL is crap. Any other installers near me wont touch it which speaks volumes. I'd love a 2nd opinion, but just cant get one. I'm on the original coil packs and leads. The car has 56k miles on it, 36k of which were on petrol. So, before I ditch my much loved and perfect condition V40 - has anyone got any ideas? If it werent for this light coming on now and again, I'd be oblivious. Just concerned that I'm damaging the engine. The car is mint in every way - tight as a nut and I want to put another 100k on it - but am worried that this OMVL system will cause a big failure some day. Johnny [edit: should say, the car is flawless on petrol. No OBD errors at all - and I tested it for a whole week on petrol. swopped coil packs a while back, misfire stayed on cyl 2] Last edited by johnny_e; Jun 11th, 2009 at 11:35.

Jun 11th, 2009, 11:56	#2
davew Senior Member Last Online: Jun 16th, 2011 15:27 Join Date: Sep 2008 Location: Nelson	Could it be the lpg injector on number 2? Or any associated hoses? This would cause a miss and running lean on that cyclinder... __________________ S80 - 301 Bhp - 450Nm

Jun 11th, 2009, 12:25	#4
davew Senior Member Last Online: Jun 16th, 2011 15:27 Join Date: Sep 2008 Location: Nelson	I am not familular with your setup, but if it looks anything like mine then your injectors will be on the other end of the 4 pipes going up in the picture. Is there anyway you can test that gas is actually coming out of number 2? Everything may be working as it should but the gas just not getting there. Maybe a blockage in the pipe. Could you swop everything over that is soley for injector 2 for injector 1? __________________ S80 - 301 Bhp - 450Nm

Jun 15th, 2009, 19:14	#8
Vallhund Junior Member Last Online: Jul 8th, 2012 15:09 Join Date: Apr 2009 Location: Reading	Misfire I got a misfire on cylinder three but only after i fitted the 'Flashlube' kit. Found that i had put the feed pipe to the Brake vacumm hose and was just running along the wall of the pipes and ending up in that cylinder. Had to drill a hole after the butterfly valve , thread it and insert the brass tube directly in the flow of the incomming mix. Got rid of the misfire. It was the only spark plug (normal plug) that was wet and it smelled the same as the Flash lube. Have , like you , also changed to Irridiums. 240 Torslanda.

Jun 11th, 2009, 12:40	#5
johnny_e Junior Member Last Online: Oct 4th, 2009 10:39 Join Date: Jul 2007 Location: County Armagh	Those 4 pipes you see are about 6 inches long and are tapped into the inlet manifold. So am i right to say that the actual injector nozzles are what's tapped into the inlet then? I am so frustrated as I've had it back to the installer well over half a dozen times. The misfire isnt there now I've put the new plugs in, but it gave a 171 yesterday. I have a feeling that a 302 will be back in due course... Once again I live in the wrong place (NI). If I was on the mainland I'd be able to bring it to an expert for a 2nd opinion. Anyone else here has steered clear of OMVL and cant help me. Thing is... I cant sell the car while this is happening either - so its catch 22.

Jun 11th, 2009, 15:26	#6
peter8315 Member Last Online: Nov 21st, 2011 15:58 Join Date: Nov 2008 Location: ilkeston	Hi, you say it was fitted about a year ago, if its still under garantee i would take it back and leave it with them until its put right, i think thats your only option, as they should be the experts on this system, regards, Pete.

Jun 11th, 2009, 15:31	#7
johnny_e Junior Member Last Online: Oct 4th, 2009 10:39 Join Date: Jul 2007 Location: County Armagh	Yes.. and no...Pete. The system was bought in 2006 for my Vauxhall at that time. I sold that and had the system transplanted to the Volvo - using an OE S/V40 tank, new plumbing, exchange rail etc. So, the likes of the ECU is 3 years old - whilst other parts are a year old. In fairness to the fitter, its been back 6+ times and he tries... but he's too quick to turn to the laptop and say that the new systems from OMVL have a slower pulse for low throttle. I'd really need someone else to look at it properly without bias. But that aint happening. I emailed FES who import OMVL kit in the UK - to see if anyone else in NI does OMVL - but I suspect thats a dead end. Do you think that continual errors such as this (albeit just happening once a day for that split second) will end in an early death of my engine? Thats what I fear - and thats whats going to mean me trading the car in. Unfortunately I aint got a fortune to spend, so will end up in a soul-less tdci. Great! (At least I've got my old Audi Coupe V6 tucked away for the weekends!)

Sep 17th, 2009, 21:02	#9
petrolhead69 Junior Member Last Online: Sep 21st, 2017 02:34 Join Date: Sep 2009 Location: west lothian	OMVL kit is usually pretty good quality, certainly better than bedini, romano and BRC IMO but positioning of the injector nozzles in the manifold is critical, it might be an idea to try some short copper or brass spuds to get the point of lpg entry closer to the inlet valve then remap. I had similar problems with a rav4 and that made a huge difference, in the end it ran better on lpg than petrol. has your installer tried flashing the gas ecu with the different firmware versions? there are different versions that use different methods of calibration and mapping that make quite a difference. Nick at FES knows his stuff, but I think he only provides tech support to installers who buy from him but if he only has 1 installer in NI and is giving a bad rep to omvl in the area he might be keen to help. are the plugs OK? i would change at least the plugs just to be sure. HT components that work perfectly fine on petrol can cause running problems on gas as lpg/air mix has at least 25% higher electrical resistance than petrol/air mix. a gentle misfire can throw the o2 sensor readings out without actually spluttering. Also check for an air leak near the lpg nozzle or a leaking petrol injector O ring good luck

Sep 17th, 2009, 21:04	#10
petrolhead69 Junior Member Last Online: Sep 21st, 2017 02:34 Join Date: Sep 2009 Location: west lothian	sorry, i missed you changed the plugs, too much cobra beer;-)

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)