Some 4mm pipe will squeeze onto 5mm fittings but not as easily as 5mm pipe will squeeze onto 6mm fittings. The V30's usually have 4mm or 6mm outlet fittings, not always interchangeable... some of those that come with 6mm fittings have a wider diameter machined hole in the rail for wider diameter thread nozzles.
SImon.
Okies, so i got some time today finally, and got the LPG injectors fitted.
Couple of issues.
First of all i got the T-Piece linked above, however i notice that the resistance of the sensor is different to the original one, and there doesnt seem to be any calibration options to change the sensor within the software? Is it close enough to work ok?
I fired it up with the temp sensor disconnected, got the software working (eventually, its shonky as fk) and warmed it up a bit, then hit the gas button and let it switch over.
It ran and didnt have the horrible vibrations that it had on the old injectors, but the engine wasnt happy, wouldnt rev, Spitting and popping etc.
I noticed that the gas pressure was showing as 1.6bar, so wasnt sure what to do about turning it up as suggested earlier.
I figured it was lean due to the smaller injectors, pondered how to fix it and decided to press the autoconfig option within the software.
It asked me to rev the engine at 3000rpm for a period of time and then said it had completed the calibration. After that the engine ran much better, revved cleanly in neutral etc. However when i took it out on the road its not right. Spluttering and generally unhappy at various points in the rev range.
I compared the map before and after, and took some screenshots, i'll post them up shortly.
Any thoughts?
@lpgc? any ideas?
While you wait for LPGC to come back, have a read of this
http://tinleytech.co.uk/help-and-advice/fine-tuning-an-aeb-manufactured-lpg-system/
Not your system, I know, but it explains the principle of sorting the rest of the mapping for other points in the rev range
I'll try some of the things in there, thanks.
I've got a vague idea of what might be going on as well.
When i last ran the autocalibration, it was running on gas, really badly, then i pressed the button to calibrate and it got better. But i've realised that its quite likely, the STFT's were maxed out trying to get enough fuel while on gas, so while its autocalibrated, its done so with the short term trims maxed out at full enrichment...
I'm hoping i can run the calibration while on petrol, where the trims will be sensible. Going to try that maybe later on tonight.
I'm also going to connect up that temp sensor and see what happens, rather than running without it.
Sorry I'm late back to the chat. I'm used to forums that list threads in order of recent activity and usually frequent them often enough to post on relevant threads, while on this forum I've so far left it to luck to keep on top of things because I haven't been using the 'track topic' facility... I've probably seemed ignorant a few times but I'll start using the topic tracker now!
You did remove the injector nozzles and drill the out to 2.5mm?
To stand good chance of proper calibration you'll need temp readings for gas vapour (and for reducer on an AEB based system) to be something like correct, because behind the scenes the system compensates fuelling for temps within a range of about 40%. With a temp sensor disconnected the temp reading will be extremely cold and under such conditions the system may subtract 30odd% of fuelling. You may get it running OK like that but then when the system does read a more accurate temp (when you do reconnect the temp sensor) fuelling will be incorrect and calibration will need to be changed again.
Autocal involves the system running on both fuels, it cannot be done without running on gas, no meaningful calibration can be done at all without running on gas. It simply takes note of petrol injector pulse duration (pinj) when running on petrol at (say) 2500rpm with no engine load, then switches to gas and takes note of pinj when running on gas. If pinj rises when it switches to gas the LPG calibration is lean so autocal increases all the numbers in your map by a calculated percentage, and vice/versa. However, if you ran on gas for a while before running autocal then this could have forced your petrol system to switch to open loop fault mode, in fault mode pinj doesn't change regardless of fuelling so autocal doesn;t see any change to pinj regardless of any changes it makes to the LPG map, so autocal cannot work properly and will likely keep making changes to the LPG map until it reaches the extreme (leaning or richening) of autocal's scope for making changes to the LPG map, which would likely make for worse LPG fuelling than if you hadn't run autocal at all. At this point don't try running on LPG again until after you've cleared any engine fault codes, reset the LPG ECU, re-entered all the basic settings in the LPG ECU and run autocal again.
Loads more to say but best to see the screenshots first. Better if you post screenshots taken after following the above advice.
Simon
which injector nozzles should i have been drilling out?!
I just bolted the rails on as they come out the box!
Sorted those screenshots, i've also uploaded the config files so maybe you can load them up and have a look? I noticed something a bit strange in the Lambda menu as well.
Original map:
https://www.dropbox.com/s/k6txepgv1egttn4/Capture-old.PNG?dl=0
Map after autotune:
https://www.dropbox.com/s/gc026raujbsjn81/Capture-new.PNG?dl=0
Strange Lambda screen, what does "fuel trim bank 2" do?, and why are the sensors set to "not connected" when they were definitely showing readings on the main screen with the engine running:
https://www.dropbox.com/s/nm87rqx4saa7gvh/lambda.PNG?dl=0
Original Config:
https://www.dropbox.com/s/rulvujcw3bajejf/M43%20YMA%204.6%20RR%20new%20plugs%20rec.cb8?dl=0
Config after Autocal:
https://www.dropbox.com/s/4mi9lb9f4xy690p/M43%20YMA%204.6%20RR%202.cb8?dl=0
Aragorn wrote:
I noticed something a bit strange in the Lambda menu as well.
Strange Lambda screen, what does "fuel trim bank 2" do?, and why are the sensors set to "not connected" when they were definitely showing readings on the main screen with the engine running:
I can help with the middle bit.
Fuel Trim Bank 2 is a +/- number which is changed to balance the gas flow to each bank of cylinders.
The sensors are set to "Not Connected" because your gas system is not connected to the Lambda sensors. It gets its timings from the petrol management system.
it IS connected to the lambdas though, in live data view they're displayed and flick around showing rich and lean as you'd expect.
The fuel trim thing makes more sense, i noticed bank 2 was acting oddly, maybe i need to put that back to zero?
Aragorn wrote:
it IS connected to the lambdas though, in live data view they're displayed and flick around showing rich and lean as you'd expect.
The fuel trim thing makes more sense, i noticed bank 2 was acting oddly, maybe i need to put that back to zero?
You know your system, so if it is actually physically connected to the lambda sensors, then see what happens when you change that setting :)
The balancing number setting goes something like this (from my setup crib sheet- it comes after getting it running approx. right with Autocalibrate)
If the engine is being run as 2 banks, when running on gas, compare the two Tinj.Petrol timings. They will be different, but if one bank is consistently more or less than the other, you should adjust the Fuel Trim Bank 2 until the timings are about the same. If Tinj.Petrol for bank 2 is, say 10% higher than bank 1, add 10 to the Fuel Trim Bank 2 figure and vice versa. The trim figure can be negative. Repeat the above until the two Tinj.Petrol values average around the same
First things first, you will need to remove the brass nozzles from the injector rails (4 on each rail, probably 12mm or 13mm spanner to remove them) and drill the jet in them out to 2.5mm.
The lambda setting won't make any difference to how the LPG system responds but since your system is wired to lambdas the correct setting will show lambda voltage on screen - it is just a facility to allow the user to monitor lambda voltage and is used for nothing else.
OB explained the bank 2 trim. At this point we (or at least I) don't know if your LPG system is wired so that what the LPG system sees as bank 1 is what the petrol system sees as bank 1 or bank 2, adjusting the bank 2 trim could effect what vehicle OBD reads as bank 1. If you have an OBD scanner it can be quite easy to tell if LPG bank 1 matches vehicle bank 1 - In OBD find which bank has the highest trim (ltft+stft), this should be on the same bank that shows the highest pinj in LPG software and adjusting bank 2 trim should mostly effect the vehicle's OBD bank 2 figures. Knowing if LPG bank matches petrol bank can avoid wasting time, because if you set calibration (without using the trim facility to start with) a trim to keep fuel trims correct for bank 1 but the LPG system is wired so it's bank 1 is actually petrol bank 2 and then you realise that you have to set a bank trim, what you'll have to do is adjust the full map and set the bank trim instead of just adjusting the bank trim. Don't set a bank trim from the outset, at least not until injectors have bedded in a bit, and don't calibrate with a bank trim set except as a last resort... need to use excessive bank trim can point to other problems that should be investigated first.
Simon
Thanks. I'll see about getting the injectors drilled out, and the temp sensor hooked up and try another go at calibration!
Right really starting to struggle with this now...
Temp sensor is fixed and reads properly.
Nozzles are drilled out and reinstalled and everything is hooked back up.
Started it on petrol, ran it up to temperature and tried an autocalibrate. However it clearly doesnt work properly. As it performs the calibration, you see the gas inj time get slowly larger and larger, and the engine runs worse and worse. When it completed, the gas map had even larger numbers in it than before and it barely ran on gas. I also noticed the lambda values seemed to stick at 0v as soon as the gas comes online. I reset the map using the button in the config and the engine ran much better on gas, but again as soon as you run autocalibrate, it cranks all the numbers right up and runs like crap again.
In the configuration, theres a setting for lambda that has either 0-5v or 5-0v, but i'm not sure which it should be set to. It was initially set to 5-0v, and i tried 0-5v with the same result. I imagine one way the ECU sees 5v as rich and one way it sees 0v as rich, but i've no idea how it should be set. I'm guessing 0v is rich, given it seems to stick on 0v when it switches to gas.
I'm also wondering about the configuration of the injectors. The manual suggests two options for injector type, Biagotti and Biagotti fast. Its set to Biagotti, but the manual suggests 3 ohm injectors should be set to biagotti fast?
Lambda sensors are 5-0V which means that 5V will be seen at lean and 0V at rich. So setting it wrong and it starts rich and just gets richer and richer. As for injector type, what have you actually got and what are your options in the software?
yep figured that out, 5-0v is correct.
The injectors are Valtek type 30's. The only options in the software were biagotti and biagotti fast.
I took a punt and set it to Biagotti FAST, re-ran the calibration and it all worked perfectly...
Theres a strange stumble when it first switches, i might take another look over the settings for change over see if i can improve that.
Otherwise it drives pretty much perfectly once on gas :)
Stumble on changeover is going to be down to changeover overlap or changeover delay, depending on what it is called in your software. It sets the delay between turning gas on and petrol off so if too low it will have no fuel for a fraction or if too high, it'll be drowning in fuel for a fraction. Both will cause a stumble, but usually it is caused when set too low.
So theres an "overlap" setting. On the old map it was set to 0.1s, on the current map its set to 2s
i'll try turning it down and see what happens!
Need to source more LPG though, the red low level light keeps flickering on and off!
Lambda sensor setting in LPG software won't make any difference to autocal, as said earlier the only reason for the connection at all is to allow the installer to see lambda voltages on screen multimeter fashion, the LPG system doesn't take any notice of lambda readings other than displaying them on screen.
Biagotti Fast is the injector setting you want.
Unless your engine is running closed loop autocal has no chance of succeeding.
You also need to have injector routing correct, i.e.each LPG injector sends fuel to the engine cylinder that it should, so if your LPG petrol injector wiring is blue red green yellow respectively for cylinders 1357 the LPG injectors that fuel those cylinders should be ABCD respectively.
Set overlap to zero... Though stumble on changeover is most often due to incorrect routing and/or LPG calibration - If routing is incorrect and changeover is sequential (thus switches each cylinder separately a brief time apart) then when it turns off petrol to a cylinder and is supposed to start sending gas to that cylinder, what happens is that cylinder gets no fuel at all but another cylinder gets both petrol and gas, result is a misfire on 2 cylinders which will occur at least twice during changeover, and this is if routing on 2 cylinders is mixed up (the minimum possible besides no mix up) , it will be worse if routing is more mixed up than just 2 cylinders. Even with sequential changeover set, the engine can run OK with some mixups with routing, because when switchover is complete all petrol injection is off and all cylinders run on LPG. Depending on ECU firmware version and software the software may have facility to aid checking routing. Incorrect routing would also mess up autocal.
Which version of software are you running? Did you 'Reset the ECU' before running autocal? Did you adjust the pressure setting? When fully warmed up and idling nicely on petrol, what pinj readings are you getting?
Instead of running Autocal, try unticking the 'sequential changeover' box for now and setting all numbers in the map to 140.
Simon
Once setting it to biagotti fast it seems to have calibrated up correctly and runs quite nicely. Switching to biagotti fast seemed to reset everything, and i had to go thru and input various settings again.
From memory pinj was around 2.5 but i'd have to look.
Once on gas driving down the road i tried some moderate accelleation and some normal crusing while keeping an eye on the lambda values and they were switching nicely in a closed loop fashion, so i'm pretty happy that the ECU is in control.
I'm pretty sure the ABCD corresponds correctly with 1357 etc. Unless someones cocked up where it interfaces with the ECU itself. But given its a 10+ year old install i'm sure someone would have picked it up before now if that was the case! I'll wind the overlap back down to 0 and see if that sorts it out.
