LPG Forum


All times are UTC



Post new topic Reply to topic  [ 91 posts ]  Go to page Previous  1, 2, 3, 4, 5  Next
Author Message
PostPosted: Sun Jun 26, 2016 8:20 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 2927
Location: Yorkshire
I'd take your word for it over the other guy Richard and I'm sure you'll be right. Still confused because I haven't been able to find pages leading up to 8, so I don't know if they make an exception for LPG or if they mention cat's or vehicle years etc? Looking at pages after 8, they do seem to say to use vehicle specific emissions figures if the vehicle can be found on the 'analyser database'. But does the analyser database contain only data for running on petrol? In the absence of data in the database (I'd assume for running on gas) the pages I've seen point towards using a 'default limit'. Can we assume the default limit is higher than the limits that the database would stipulate for, say, a 2000+ vehicle if it were presented running on petrol? And if that is the case, isn't there some truth in what the MOT guy said?

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: Sun Jun 26, 2016 9:19 pm 
Advanced Member

Joined: Wed Apr 09, 2008 9:00 am
Posts: 7860
Images: 0
Location: Peterborough
The pages leading up to 8 are the various tests and reasons for failure which on the website are here http://www.motuk.co.uk/manual_730.htm. Then you get to page 6 which is the start of the flowchart, the non-cat test http://www.motuk.co.uk/images/730_newnoncat.pdf. Page 7 then gives the information on the test proces which is as shown on the website below where that test appears.

_________________
'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: Mon Jun 27, 2016 10:29 am 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 2927
Location: Yorkshire
Not arguing with you mate but I'm still not sure if MOT man's comments are far wrong...

In case of that 2000+ car with a cat fitted (or even a later car, say one that must have a cat fitted to be able to stand any chance of passing the test), does the tester take the branch for 'fuel type LPG' on P6 even though the page heading is 'non cat'? Or does he refer to further pages that seem to apply to later vehicles that must be fitted with a cat and then (assuming he cannot find an entry on the database for this car running on LPG) take the branch where 'exact vehicle cannot be found on the database' which will go on to instruct him to use 'default test limits'? Is there a grey area here?

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: Mon Jun 27, 2016 11:29 am 
Advanced Member

Joined: Wed Apr 09, 2008 9:00 am
Posts: 7860
Images: 0
Location: Peterborough
No, no grey area unless the tester isn't following the flowchart as it is intended. The heading is Non-Cat test as that is the point you've got to in the flowchart, the further ones are the generic Cat test and the specific limits tests depending on how far through the flowchart you get before you find something that exactly matches the car being tested. He starts at Start on page 6, gets to the 'first used after 1992', follows the No path which then takes him to 'Is the fuel type gas?' and if it is, he does the non-Cat test. At that point he's finished. If he were to skip over that page and start midway through the flowchart sometime after Start, then he could go down the other routes but if the car isn't running on petrol, none of the options or limits apply.

Whether a cat is fitted or not is irrelevant for the purposes of the emissions test but it is checked under section 7.1.3 (http://www.motuk.co.uk/manual_710.htm) which is on page 1 of section 7.1 in the printed book. You'll note that it says "On vehicles that qualify for a full cat emissions test, check the presence of the catalytic converter." so, as a car running on LPG doesn't qualify for a full cat emissions test, the check for the presence of a cat isn't required. However, not all testers are as clued up as they should be so will check for the presence of a cat anyway. If you want to be a smartarse you can print of the relevant page and take them with you or just suggest he checks his manual. However, if you do that you need to be 100% certain that everything else is absolutely spot on as he'll often not take kindly to be told how to do his job and will find something else to fail it on.

_________________
'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: Mon Jun 27, 2016 12:32 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 2927
Location: Yorkshire
Thanks for that Gilbert, I learned something there.

But in that case, isn't it true that any vehicle presented for MOT running on LPG only has to pass the same standard of emissions test that applies to vehicles first used in 1986, regardless of fuel injection, carbs, cat or no cat, single point LPG or sequential LPG system? Likely to be a far more lenient emissions test than for later models of vehicle where, in case of running on petrol, specific vehicle emissions data can be found on the analyser database? Especially if the MOT guy hasn't noted to divide HC readings by the hectane equivalence number relevant to the emissions machine used.

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: Mon Jun 27, 2016 4:40 pm 
Advanced Member

Joined: Wed Apr 09, 2008 9:00 am
Posts: 7860
Images: 0
Location: Peterborough
LPGC wrote:
Thanks for that Gilbert, I learned something there.

But in that case, isn't it true that any vehicle presented for MOT running on LPG only has to pass the same standard of emissions test that applies to vehicles first used in 1986, regardless of fuel injection, carbs, cat or no cat, single point LPG or sequential LPG system? Likely to be a far more lenient emissions test than for later models of vehicle where, in case of running on petrol, specific vehicle emissions data can be found on the analyser database?
Yup, absolutely spot on. Irrespective of year, whether it has cats or not, fuel injection or carb, etc, it is tested to the same lenient standard. If the answer to the 'Is it running on gas?' question is No, then you continue along the flowchart and test to whatever standard you get to that matches.
LPGC wrote:
Especially if the MOT guy hasn't noted to divide HC readings by the hectane equivalence number relevant to the emissions machine used.
The modern computer driven machines they use these days do the correction for you as soon as you tell it the fuel type is LPG, it's only if they are still using a stand alone tester that they have to do the sums for themselves.

_________________
'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: Tue Jun 28, 2016 8:58 am 
New member

Joined: Mon Jan 31, 2011 8:48 pm
Posts: 166
My MOT tester does the test as mentioned above, where emission limits are quite lenient on LPG.

Back to the topic....interestingly, out of curiosity, I plugged in my Vectra and found that this too had a very noticeable difference in tone when individual injectors are switched off. I've been running this car for over 4 years now with no major problems, getting 4.65 miles per liter of LPG at worst. Assume that's ok for a 2.5 V6 driven fairly hard?

I've checked all the injector wiring on the Bongo and all looks ok to me, although it would be easier if they stuck to the same colour coding on the cut injector loom, and the feeds to each LPG injector.
I've done several 'autocalibrate' procedures now but at the end of each I get the message 'calibration completed, NOT OPTIMAL' or something like this.
The Bongo has one lambda fitted, and I've been looking at this while driving but it tends to jump about all over the place.
I will try to get someone to sit with the laptop and make adjustments whilst I drive, but don't fully understand the 'fine tuning' adjustments as described by Tinley.
Any help with these would be appreciated... :-)


Top
 Profile  
Reply with quote  
PostPosted: Tue Jun 28, 2016 11:59 am 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 2927
Location: Yorkshire
@Gilbert - OK mate, Cheers Richard.

@Colin

If you look in the 'Display' screen there should be a slide gauge that in theory reflects if your combination of pressure and nozzle size are too low, OK or too big, with perfect being in the middle of the slide gauge. Where Autocal says 'not optimal' the slide gauge will be outside the range that is supposedly OK but experienced pros may ignore the slider in certain situations. With a fully warmed up idling engine (with no engine loads such as aircon or electrics turned on), all engine OBD error codes cleared and running on petrol, what are petrol injector pulse duration figures showing? If you switch to gas, what do the same figures show now? What are LPG injector pulse durations? What injectors are fitted / selected in software? What are reducer temp and gas temp readings?

As said, particularly on 6 cylinder engines, particularly with certain ECU's, you can get a very noticeable difference when switching a channel back to petrol even if calibration is spot on. But it is necessary to fettle calibration after autocal, not only for idle but at all engine loads. Since autocal is done at fast idle with AEB, you can half expect calibration to be near correct for fast idle but the engine doesn't often run at fast idle with no load.

Are you sure the Bongo only has one lambda fitted (what year is it again?). You'e not confusing post cat probe(s) with pre-cat probes are you? The Bongo may have 2 pre cat probes (even if it has only one post cat probe). Post cat probes are almost always narrow band, so it is possible to wire a voltmeter or the voltmeter that is built into the LPG ECU (purple wires on AEB) to them but there isn't much point to wiring to them.. You cannot get a mixture reading from a wide band probe using any type of voltmeter, including the ones built into LPG ECU's, depending on the year of the Bongo it may have a wide band probe fitted.

What year is the Bongo? Does it have a mechanical fuel pressure regulator fitted? Without re-reading the thread, don't you have an OBD scan tool that shows live data including fuel trims? If so, don't bother connecting to lambda even in the case pre cat probe(s) are narrow band.. Instead, calibrate while reading live fuel trim data. Also, check the scan tool to see if there is live data for fuel pressure.. If there is a reading for fuel pressure, check to see how switching between gas/petrol effects the reading. If the reading rises to a steady peak when running on LPG then you will need to fit a solenoid controlled fuel return system.

You do want pre-cat narrow band lambda readings to jump about all over the place - they should constantly fluctuate below 0.5v and above 0.5v. Post cat narrow band readings may hold a more steady voltage.

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: Tue Jun 28, 2016 2:07 pm 
New member

Joined: Mon Jan 31, 2011 8:48 pm
Posts: 166
Hi Simon, definitely only one lambda, 0-1v. It's a '98 Bongo, doesn't have the usual D shape diagnostic connector. Has another one, which needs a special reader I'm told because the adapter will not work.
Will 'AcGasSynchro' work with a King system? looks like an easier system to work with regarding on the go calibration?


Top
 Profile  
Reply with quote  
PostPosted: Tue Jun 28, 2016 6:28 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 2927
Location: Yorkshire
Ahh, if I had re-read the thread I would have known it wouldn't have wide band lambda probes, still would have suspected it would have 2 pre cat 0-1v probes on a V6.

You will have to use the King software but that isn't a negative. The other software works only with AC(Stag) based systems (one or two other sticker'ed ECUs are actually AC Stag but not King, which is AEB).

Will need answers to the other questions I asked in post above to be able to advise whether it seems you have the basics correct. In addition, you will need to drive flat out of on petrol while watching Pinj - what is the maximum figure you noted? Above a certain load do the figures seem to suddenly fall to around half what they just were? This is to see if the older Mazda runs group or sequential injection and to see if it does the Mazda peculiarity of switching from sequential to group injection above a certain load (sometimes only above certain rpm). Most likely it will always run sequential and not do the Mazda injection methodology change but these two points are also important basics.

When the basics are correct, calibration of your '98 Bongo will be a simple case of driving on petrol with a steady throttle opening, noting Pinj figure, switching to LPG and noting any change. If Pinj goes up, slightly increase all the numbers on the row where the ball is in the 'map' screen in software (or decrease numbers on the row if Pinj goes down). Drive the car with throttle opening such that the ball starts off in the low Pinj rows (top of screen) and repeat for every row coming down the screen in order. If there is an injection methodology change there well also be a change to make in the 'Leaning on Mazda' box.

Things are not always as simple as they seem, eh Col! :wink:

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: Tue Jun 28, 2016 8:31 pm 
New member

Joined: Mon Jan 31, 2011 8:48 pm
Posts: 166
I've upped the reducer pressure from .9 to 1.1 and done another autocalibrate. The 'slider' is now sitting in the middle. I will be using the van for work this week but will try to do as you suggest at the weekend if I can get someone to help... :-)


Top
 Profile  
Reply with quote  
PostPosted: Fri Jul 01, 2016 1:31 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 2927
Location: Yorkshire
OK Col

_________________
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: Mon Jul 04, 2016 4:09 pm 
New member

Joined: Mon Jan 31, 2011 8:48 pm
Posts: 166
I had a go at calibrating over the weekend... tried to keep the dot on the same row but this was impossible. With the revs kept steady the dot was moving up and down between the top 5 rows. Did this for each rev row across the top. Some pinj timings were very similar but some I changed (mainly added between 5 & 10%) I just changed the top 5 rows because the dot rarely went below this. Is the dot supposed to fluctuate like this?


Top
 Profile  
Reply with quote  
PostPosted: Mon Jul 04, 2016 5:34 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 2927
Location: Yorkshire
Was the engine surging? Is the dot steady on petrol? Did you have AC etc turned off?

_________________
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: Mon Jul 04, 2016 5:46 pm 
New member

Joined: Mon Jan 31, 2011 8:48 pm
Posts: 166
LPGC wrote:
Was the engine surging? Is the dot steady on petrol? Did you have AC etc turned off?


The engine seems to be running as normal. The dot fluctuated on Petrol and lpg the same. Air.con not on.


Top
 Profile  
Reply with quote  
PostPosted: Mon Jul 04, 2016 6:59 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 2927
Location: Yorkshire
Have a look in the 'injector check' screen. Are the figures jumping around there too? Are any errors listed in the 'diagnosis' section?
Did you connect the rpm wire? In 'changeover' screen is there a tick in the 'revolution signal type' box? Does the switch in cab stay lit up?

In any screen, bottom left of the screen near the petrol pump graphic there is a row of 4 dots - are any of those dots lighting up?

You may or may not have stumbled upon one of the issues I have previously mentioned AEB systems seem to have when installed on some 6 cylinder applications, too early to tell. Save your settings as they are, then assuming you set all other settings correctly - In 'modify carb' screen try changing the 4 settings in the grouping box related to extra injection (2 tick boxes, slide bar and box to enter a figure in but don't enter a figure above around 2 in the box).

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: Mon Jul 04, 2016 7:49 pm 
New member

Joined: Mon Jan 31, 2011 8:48 pm
Posts: 166
LPGC wrote:
Have a look in the 'injector check' screen. Are the figures jumping around there too? The pinj jump around, for example at tickover (845-865 revs) they go between 1.93 and 2.22 Are any errors listed in the 'diagnosis' section? no
Did you connect the rpm wire? yes In 'changeover' screen is there a tick in the 'revolution signal type' box? yes Does the switch in cab stay lit up? yes

In any screen, bottom left of the screen near the petrol pump graphic there is a row of 4 dots - are any of those dots lighting up? no, none of the vertical line of 4 dots are lit

You may or may not have stumbled upon one of the issues I have previously mentioned AEB systems seem to have when installed on some 6 cylinder applications, too early to tell. Save your settings as they are, then assuming you set all other settings correctly - In 'modify carb' screen try changing the 4 settings in the grouping box related to extra injection (2 tick boxes, slide bar and box to enter a figure in but don't enter a figure above around 2 in the box). The extra inj sensitivity box is already ticked. In the box is 2ms. Extra Injection Ident time = 1.4ms

Simon


Should the revs be jumping around slightly eg 845-865 at tickover? Would this be causing the pinj to do the same?


Top
 Profile  
Reply with quote  
PostPosted: Mon Jul 04, 2016 8:56 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 2927
Location: Yorkshire
The revs may actually be jumping between 845-865, it is if they occasionally jump to silly figures that there'd be need for concern regards rpm. Rpm won't affect injector duration readings.

There isn't need to focus much on rpm, calibration isn't much to do with rpm, it is more to do with reading injector duration correctly, so it is more concerning that the ball jumps up and down than left to right,

For help, will need answers to the above questions.

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: Tue Jul 05, 2016 7:03 am 
New member

Joined: Mon Jan 31, 2011 8:48 pm
Posts: 166
Hi Simon, the answers to above questions I put in bold type above :-)


Top
 Profile  
Reply with quote  
PostPosted: Tue Jul 05, 2016 7:30 pm 
Installer

Joined: Wed Sep 29, 2010 5:01 pm
Posts: 2927
Location: Yorkshire
Sorry, I didn't think to read a quote of myself..

Before you make any changes, what happens when you switch to gas (How does the engine run? what happens to Pinj)? What is the range of figures in your map?

For Pinj to jump between 1.93 and 2.2 isn't too unusual, what threw me was you saying the dot jumped up and down between the top 5 rows because the top 5 rows correspond to a much wider Pinj range than 1.93 to 2.2... Or am I missing something here?

In the extra injection group of twiddle factors, first try moving the slide bar all the way to the left and note any changes, then try unticking the 'extrainj sensitivity' box and note any changes.

Did you drive flat out on petrol (1) To find maximum Pinj reading? (2) To see if Pinj suddenly falls to around half it's value above a certain engine load? If (2) is not true and (1) is less than 10ms, then in 'Changeover' screen try setting 'Inj:' to 'full group' (which will require re-calibration).

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  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 91 posts ]  Go to page Previous  1, 2, 3, 4, 5  Next

All times are UTC


Who is online

Users browsing this forum: No registered users and 4 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:  
Powered by phpBB® Forum Software © phpBB Group