LPG Forum


All times are UTC



Post new topic Reply to topic  [ 47 posts ]  Go to page 1, 2, 3  Next
Author Message
PostPosted: Tue Nov 17, 2015 2:00 pm 
New member

Joined: Sun Jul 24, 2011 1:37 pm
Posts: 31
I've got a 4.7 V8 with an OMVL Dream XXI conversion.

When I kick down on the jeep I get bad misfiring and the revs do not rise.

New spark plugs and leads.

I've ordered new filters as it feels like a fuel restriction to me. Have also ordered the diagnostic cable and software so I can have a look and see what's going on.

Any other things I should be looking at?

If the vaporiser was incorrectly sized what would the symptoms be?

Thanks

Tom


Top
 Profile  
Reply with quote  
PostPosted: Wed Nov 18, 2015 6:54 pm 
New member

Joined: Sun Jul 24, 2011 1:37 pm
Posts: 31
Anyone?


Top
 Profile  
Reply with quote  
PostPosted: Wed Nov 18, 2015 8:58 pm 
Advanced Member

Joined: Wed Apr 09, 2008 9:00 am
Posts: 7897
Images: 0
Location: Peterborough
If the vaporiser was undersized it would be unable to supply sufficient gas at times of high demand so might cause a misfire but it would more likely drop back to petrol as the pressure drops and the ECU sees it as having run out of gas. You need to get a computer hooked up to it so you can see what happens when you boot it.

_________________
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

Proud to be a member of the YCHJCYA2PDTHFH club.


Top
 Profile  
Reply with quote  
PostPosted: Wed Nov 18, 2015 9:51 pm 
New member

Joined: Sun Jul 24, 2011 1:37 pm
Posts: 31
Thanks - that's my thought too.

I've got the OMVL software and cable so can have a play at the weekend.

I've the new filters too - the filter that goes in the vaporiser was misshapen so have a new one their and bought a new 12mm filter for the vaporiser to injectors line which is a lot bigger than the existing 12mm filter.

Hopefully will have time to play at the weekend.

Tom


Top
 Profile  
Reply with quote  
PostPosted: Wed Nov 18, 2015 11:56 pm 
Installer

Joined: Wed Jul 27, 2011 7:21 pm
Posts: 3733
Location: Midlands
It would run out of legs quicker than kick down. Do you know what vaporiser it is ?
It could very well be a blocked filter. Or pressure drift on the reducer.? I would up the reducer pressure to 1.4 bar before touching the actual map. And change the filters as a matter of course.


Top
 Profile  
Reply with quote  
PostPosted: Thu Nov 19, 2015 6:36 am 
New member

Joined: Sun Jul 24, 2011 1:37 pm
Posts: 31
I'm not sure what the vaporiser is - will have a look again for a label at the weekend.

There's a hex head on the side of the vaporiser - is that the pressure adjustment?

On my old single point kits I had to drain the heavy ends. Is that the same in this kit and where from?

Thanks

Tom


Top
 Profile  
Reply with quote  
PostPosted: Thu Nov 19, 2015 4:02 pm 
Installer

Joined: Wed Jul 27, 2011 7:21 pm
Posts: 3733
Location: Midlands
If you can link a picture (photo bucket or similar) of the reducer/vaporiser and the sticker. I'm sure we could point you in the right direction between us !
You don't really need to drain heavy ends from the injection reducers. They are running a lot higher pressure. So it just gets sucked into the filters generally. Once warm enough it can pass through injectors successfully as well.


Top
 Profile  
Reply with quote  
PostPosted: Thu Nov 19, 2015 6:29 pm 
New member

Joined: Sun Jul 24, 2011 1:37 pm
Posts: 31
Will do. Hope to get home a bit earlier tomorrow so I'll pop a few pics up.

Thanks for the help.


Top
 Profile  
Reply with quote  
PostPosted: Thu Nov 19, 2015 10:11 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 3012
Location: Yorkshire
We don't know what components are fitted yet, how long the system has been installed, or if 'kickdown' means in gear under load (most likely) or just blipping the throttle in neutral...

An older OMVL system (with metal bodied OMVL injectors) might be expected to have worn injectors by now...

Gilbertd wrote:
You need to get a computer hooked up to it so you can see what happens when you boot it.
All agreed on that, this would also help ID broken map sensor, temp sensors, reducer pressure etc, but may not directly help ID worn injectors.

topcat2006 wrote:
Any other things I should be looking at?
Can you hear a louder ticking noise from any particular (worn) injector compared to others? Are all vacuum lines properly connected (especially check vac iine to reducer and pressure sensor). If you disconnect the vac line from reducer, does any gas come out of the reducer vac port (it shouldn't)?

topcat2006 wrote:
If the vaporiser was incorrectly sized what would the symptoms be?
If it really is all OMVL kit it will most likely have an OMVL Dream reducer, and more specifically an OMVL Dream HP reducer (double springs acting on diaghpram), in which case should give 1.7 bar anyway (if it isn't an OMVL reducer it isn't all OMVL kit). Suppliers of OMVL V8 kits tended to supply OMVL Dream HP reducers (even in recent times). An incorrectly sized / setup reducer isn't quite the same problem for these sequential systems as it is for single point mixer systems - If everything else is correct then with too low a pressure or underspec reducer the system will go either go beep beep and switch back to petrol or flash the amber (running on gas indicator) LED (to show momentarily running on petrol due to gas injector full duration) when you boot it... The more recent Dream reducers are not as capable on powerful engines as older Dream reducers, it is possible a more recent Dream (or OMVL CPR) reducer) could cause the beep beep or flashing, but unlikely. Far more likely there is a fault, rather than an issue with component spec.

Simon

_________________
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240


Top
 Profile  
Reply with quote  
PostPosted: Fri Nov 20, 2015 5:46 pm 
New member

Joined: Sun Jul 24, 2011 1:37 pm
Posts: 31
Ok, some pictures. Sorry about the quality, it was dark when I got home and the vaporiser is installed in the most awkward place.

Image

Image

Image

Image

Image

Image

There are no ticking noises when the engine runs - on tick over it runs sweet as a nut.

Kick down is just that. Full throttle under load causing the gearbox to kickdown one or two gears.

When the misfiring/juddering occurs there is no beeping or flashing from the changeover switch on the dash. The changeover switch is square, has tank level (a red led for empty and green led's for parts full), petrol in the bottom and gas and a single switch you press once to go on petrol and press once to go on LPG. It's the same switch as pictures on the Tinley Tech website for an OMVL Dream kit.

The tank was full.

The jeep has just had new valve seats fitted as it had one fall out. My worry is that the vehicle is running lean. I have also bought a flash lube kit to install just in case.

Tom


Top
 Profile  
Reply with quote  
PostPosted: Fri Nov 20, 2015 7:02 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 3012
Location: Yorkshire
That's an OMVL Piro system, you need a very specific Piro interface cable and software to talk to it and you will need to talk to it...
Since it's Piro you should discount my above point on flashing the amber LED at injector full duration. Piro has it's own unique set of issues and can do strange things with fuelling particularly around 3000rpm, can be fussy to set up but I've converted maybe 6 4.7 Jeeps with Piro and not had any problems other than taking more time than usual to calibrate properly. Unlike other AEB systems it has a completely separate map for each engine bank (no fuel trim bank 2 feature) - If someone had previously tampered with it without knowing the system too well they could really mess things up, that's if it was calibrated properly in the first place..

You have the Dream reducer (most likely the HP 1.7 bar model, if you clean that sticker on the reducer it'll probably say HP) and you have the later (but not latest) type OMVL metal bodied injectors (not as reliable as latest type).

Simon

_________________
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240


Top
 Profile  
Reply with quote  
PostPosted: Fri Nov 20, 2015 7:24 pm 
New member

Joined: Sun Jul 24, 2011 1:37 pm
Posts: 31
Thanks Simon,

How do you know it's a Piro as the label on the ECU says Dream XXI P. Is that what the P stands for?

Does that mean the cable that I bought from Tinley Texh is incorrect (the connector on the cable fits the ECU). Edited - yes it's a Piro cable I bought.

How does one calibrate it?

Is the Vaporiser big enough?

Thanks

Tom


Top
 Profile  
Reply with quote  
PostPosted: Fri Nov 20, 2015 8:42 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 3012
Location: Yorkshire
topcat2006 wrote:
How do you know it's a Piro as the label on the ECU says Dream XXI P. Is that what the P stands for?
Does that mean the cable that I bought from Tinley Texh is incorrect (the connector on the cable fits the ECU). Edited - yes it's a Piro cable I bought.

How does one calibrate it?

Is the Vaporiser big enough?

Thanks

Tom

That is what the P stands for, also it's a different shape ECU.
Hehe so yes you have the correct cable, different plug on it to other systems anyway.
Vap is certainly capable enough.
We don't know if any parts fitted are not working properly yet though...

Best advice on calibration, don't tamper with any settings for now! Let's presume it was running OK with calibration set how it is now but some other fault caused the problem you're seeing. Best to use the software only for looking at readings and settings... Don't run a wizard, exit a wizard if one automatically starts.. Just tell us what numbers are on screen for manifold pressure, gas pressure, reducer temp, gas temp, if rpm reading matches tacho. Do that lot while engine is idling and again when engine is under moderate load (60mph on flat in gear), if you have an OBD live data reader that you can use to note and tell us fuel trims from under both conditions so much the better (and you'd be advised to have one if you go on to attempt calibration anyway). In the 'map' screen click on Bank1 then click on Bank2, lot's of numbers in each, numbers should be similar between bank1 and bank2, numbers in both should get smaller towards bottom of screen...?

If it does need calibrating - Even if this were a new system with all known good parts, would really be best to let a pro familiar with Piro calibrate it. Further advantages on your old system would be such pro would know how to ID faulty/worn components and somewhat address the 3000rpm issue. Piro was/is a work in progress that will never be finished, the 'P' was supposedly to supersede 'N' type systems like OMVL Dream XXI N, Romano RIS N, but wasn't as good as the former (which are more common, still produced and still developed). It has quirks including combinations of software and firmware that won't work properly or at all together. Some software versions have a wizard that supposedly takes you through the setup process after which 'job should be done' but isn't by a long shot, other versions of software don't have the Wizard... Possible to describe calibration but a lot of iffs and buts to handicap attempts, particularly to describe to someone not familiar with calibrating other LPG systems.

There can't have been that many installers fitting Piro on 4.7 Jeeps, I might even have fitted this but haven't recognised my work from the pics you posted (tend to think I didn't). Dai (Classicswede) might know better about numbers of Piros on 4.7 Jeeps (worked for supplier of this system back in the day) than me. Would be interesting to see a zoomed out view of the install and ask Dai how many Piro's he reckons are fitted on 4.7 Jeeps..

Simon

_________________
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240


Last edited by LPGC on Fri Nov 20, 2015 8:58 pm, edited 1 time in total.

Top
 Profile  
Reply with quote  
PostPosted: Fri Nov 20, 2015 8:56 pm 
New member

Joined: Sun Jul 24, 2011 1:37 pm
Posts: 31
Thanks Simon.

I'll have a gander tomorrow once I've changed the oil and filters and see what other info I can get.

There is a sticker in the back of the jeep saying converted by LPG Autos and a 01902 number. I did try emailing them from their website but the email bounced back.

Tom


Top
 Profile  
Reply with quote  
PostPosted: Fri Nov 20, 2015 9:16 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 3012
Location: Yorkshire
No probs,

Dunno where you are but if you're not too far away you might consider coming to me :lol:

I obviously had the cable having installed and sorted out a great number of Piro installs (especially when they were in fashion)... But earlier this year I visited another premises to convert a big Yank RV (another with 400L worth of tanks) and might have left a bag full of my interface cables in the RV, in the bag was my Piro cable... Phoning the guy later I asked 'You haven't seen a bag full of cables have you?'. He said 'No but I'll drive the 20 miles to where RV is stored to have a look in it tomorrow', then phoned to say 'No it's not here', then phoned a few times to asking questions about 'What are those cables for, anyway...?'. Hmmm!

Spent £hundreds replacing most other cables but not yet the Piro cable (very seldom needed). So, would diagnose and calibrate your system for the price of your cable(!), including sorting any piping issues (thinking along the lines of in case vap pipes are an issue)... But if nobody has messed your calibration up since installation and it ran OK when installed I'd guess you'll need a part replacing, which would cost you the additional... But 95% you'd go away a happy man with Jeep running great on LPG, anticipating new parts not costing a great deal, or 100% if you'd fork out to sort a major issue such as broken ECU for which the most sensible repair would probably be an upgrade to an N type ECU including different wiring loom.

Simon

_________________
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240


Top
 Profile  
Reply with quote  
PostPosted: Fri Nov 20, 2015 9:29 pm 
New member

Joined: Sun Jul 24, 2011 1:37 pm
Posts: 31
Simon, that's a very kind offer, thank you.

Be warned - i'm liable to ask lots of questions and watch you. I'm an Engineer by trade and I work with industrial control systems so I have a natural interest.

Where are you based? I'm Stroud, Gloucestershire.

Tom


Top
 Profile  
Reply with quote  
PostPosted: Fri Nov 20, 2015 9:57 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 3012
Location: Yorkshire
Hello Tom,

I'm in mid Yorkshire... I say mid because I'm about 400 yards from the the combined border between North, South and West Yorkshire. South Elmsall near Doncaster (or sometimes I say near Pontefract or near Barnsley depending on if the customer is North, South, East or West of me)..!

Google Maps reckons you're 160 miles from me, or 57 miles from Tubbs (installer, my mate on this forum), I dunno if Tubbs would sort you out, if he'd buy the cable from you, how you regard driving....

A lot of customers tend to be engineers, I enjoy being explanative etc so that's good!

Simon

_________________
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240


Last edited by LPGC on Fri Nov 20, 2015 10:01 pm, edited 1 time in total.

Top
 Profile  
Reply with quote  
PostPosted: Fri Nov 20, 2015 10:00 pm 
New member

Joined: Sun Jul 24, 2011 1:37 pm
Posts: 31
Hmm. A bit far for a day trip - but maybe something for the spring and a long weekend at a campsite!

Otherwise I have some time off over Christmas depending on what your working.


I'll have a look at the weekend and see if we come up with anything obvious and then let's plan from there.

Tom


Top
 Profile  
Reply with quote  
PostPosted: Fri Nov 20, 2015 10:16 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 3012
Location: Yorkshire
OK Tom, will be busy on Saturday until 5pm but Sunday would be OK, other than that no problem other days or over spring and can recommend a great nearby campsite with lake, woodland walks and listed house. I generally do work all Xmas.

Reads like you mean a weekend further into the future but just in case you mean this weekend - I may not reply tonight now but will pick up tomorrow (Sat) around mid day. Even Sat evening would be OK, even though my next reply may be midday Sat.

Regards,

Simon

_________________
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240


Last edited by LPGC on Fri Nov 20, 2015 10:20 pm, edited 1 time in total.

Top
 Profile  
Reply with quote  
PostPosted: Fri Nov 20, 2015 10:18 pm 
New member

Joined: Sun Jul 24, 2011 1:37 pm
Posts: 31
Thanks Simon. I'll collect as much data as I can and get some pics and hopefully that'll give an indication as to where the problem is.

You never know (wishful thinking) the new filters may cure it.....

Tom


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 47 posts ]  Go to page 1, 2, 3  Next

All times are UTC


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group