blueplasticsoulman wrote:
I literally did my throttle cable today. It was slack. I reckon about 4mm of adjustment. Tightened it up and honest, the car picks up much better. I was only saying before how I thought my other p38 felt faster/sportier or whatever. Can't believe the difference a couple of mm has made. (said no woman ever!) lol
With slack cable you'd have to press the accelerator further to open the throttle the same amount, might not even be able to get to WOT, and with these models having long throttle pedal travel a bit of slack might make for a fair bit of difference to how far you have to press the accelerator to open the throttle valve the same extent. Can't affect TPS though because that sits on the same shaft as the actual throttle flap.
Simon
Agreed with Aragorn on autoboxes / TC's. The TC in my car (Grand Voyager) locks up in top (4th), will lock in 3rd if it's been sat in 3rd for a long while or if the shifter is set to 3. It will lock up in 2nd if the gearbox temp gets very high... When TC's slip they generate heat, too much heat is very bad for autoboxes. I thought about fooling the box temp sensor to make the box lock in 2nd at the press of a switch, would probably help prevent box getting hot when pulling the caravan up that steep incline on the A30... But I'll probably use the ML for towing instead lol, finally reserved a bit of time to work on it and it passed it's MOT the other day.
Engine load figures are fairly abstract - Is 100% load at the red line with full throttle, or is it at full throttle at rpm where the engine makes most power (which could be below red line rpm), or is it at torque peak rpm (which is well below red line) with full throttle? Then there's part loads e.g. 50%, is this at half throttle at the red line, or at full throttle at half red line rpm, or both? Because they place very different demands on the engine, fuelling and ignition timing won't be the same between them... The load figure cannot be used directly for ignition timing or for fuelling. Some LPG ECU's calculate engine load but there is always the disclaimer about it's abstract nature. Some allow you to set a change back to petrol after a certain engine load, but you'd be hard pressed to guess what combinations of rpm and throttle position would set the switchback condition.
A lot of OBD2 compatible cars with MAF sensors show g/s in live data, I take this to be grams per second...Can confirm if grams / seconds interpretations are near correct... An engine of around 1.6litres generally reads around 3g/s at idle when warm, which would equate to 10800 grams per hour, 10.8Kg. Given stochiometric ratio of 14.7:1 for petrol this would equate to 0.74Kg of petrol burned per hour and since petrol has a density of 0.77Kg per litre this equates to around a litre per hour (0.22 gallons per hour) which won't be far off for warm idle for a 1.6. A car with this engine might do 40mpg at 60mph which is 1.5 gallons per hour, thus using 6.8 times as much air (20.4g/s) and fuel to cruise at 60 than sat at idle, which also makes sense.
Simon
Your Bigas injectors will use 4mm internal diameter pipe, V30s usually come with the nozzles to suit the same diameter pipe but can come with nozzles to suit 6mm internal diameter pipe - make sure you stipulate V30s with nozzles to suit 4mm internal diameter pipe and 10mm gas inlets when ordering. Also order a combined inline gas temp sensor / pressure take off like this (http://www.lpgshop.co.uk/12mm-omvl-inline-temperature-sensor-with-pressure-out/). This is listed as 12mm but is more like 11mm and most 10mm pipes will fit, but ask if they can sell you a 10mm one instead before buying. Tinleytech is more likely to be able to supply a 10mm one.
There is another way of going about it - buy V30s with 12mm inlets, use 12mm pipe, use a 2 entry 2 outlet 11mm pipe fitting filter. 10mm pipe then runs between reducer outlets and filter, 11mm pipe between filter and injectors.
4mm Pipe, similar electrical properties, similar injector response and similar physical dimensions were reasons I suggested the V30s.
Simon
Partly off subject but I recently bought another Grand Voyager. I'm in Yorkshire, the seller was in Derby, I only went to view because my son was going to London that day so could drop me off en-route, and I could catch the train back if I didn't buy. I sussed the misfiring was due to the jetwashed plug leads (nice electo-storm display peaking under the partly closed bonnet), that it needed a drivers side front wheel bearing and that the heater zone control was stuck to defrost due to broken teeth on the heater box.. I paid half the asking price which was already half the going rate and nursed it home like that, next day had it all running perfectly because I already had the parts to chuck on it from another car lol.
Simon
No probs mate, yes get in touch if you want to bring it in.
If you're going to download software from AC you should go for V11.2.0.7, it's the only PC version on Stag's site that should work with your system.
If this software connects it will probably ask if you want to update firmware, don't update firmware.
No point the installer giving LPGShop control over your PC if the problem was the physical connection between your PC and the LPG system lol. £90 to give the installer the opportunity to demonstrate their incompetence.
Simon
Possible you have a dodgy injector, in which case would most likely be on bank1, but neither is by any means certain.
I suppose you could do the stethoscope test, bit of narrow pipe in ear while holding open end to each LPG injector in turn, see if any injector(s) make a different noise to the majority of injectors, not a conclusive test but can give some insights about condition of injectors. / Swap injectors on sides of the engine, see if what's happening with trims now goes the opposite way after moving them.
Simon
Thanks to those who've mentioned me above... Dazer, I'm the Simon mentioned.
Stag software I keep installed are V11, V10, V7, V2, V1 and Qbox V0.16, with those versions can connect to any Stag labelled sequential system (and Stag clones, and other systems that use an interface with compatible pinout). All of the later versions should connect to ISA2, would start with V11 and go back through the versions I listed if you have problems connecting but if you get to V7 on my list you might as well give up trying with the lead you're using.
This is one of the best Stag compatible interfaces (http://www.lpgshop.co.uk/ac-stag-usb-ftdi-diagnostic-interface/)
Simon
Unlikely I know, but a dodgy TPS would have potential to mess up both gear changes and fuelling..
Likely that the connection issue is as Gilbert said, wrong cable, or the installer might have tried to use wrong Stag software. Some installers that recently started fitting Stag may only have Stag Qbox software, or installers that dabbled with Stag in it's early days may only have older Stag software, neither of which are compatible with ISA2, Some connection issues can be sorted as easily as pulling the LPG system fuse and putting back in. If the installer didn't know what cable or software to use for such a common system I wouldn't be very confident of their abilities...
A lot of installers who fit Stag hardly bother to address pressure and nozzle size. For any type of injectors selected in software the Stag will suggest a minimum allowable pulse duration, sometimes this can mean running rich at idle and during over-run (but the real issue in the case of a P38 would be pressure / nozzle size). Most installers who fit Stag don't bother to do a proper manual job of calibration, instead they rely on the system's auto-tuning facility... This doesn't work well in the best of circumstances but if the vehicle develops a fault (like a broken lambda) the autotune can really mess up calibration if left enabled.
Simon
Yeh, in simple terms the higher pressure compensates for smaller nozzles, if you look at it in a bit more detail it should change the shape of the map in the low load area more than the high load area - but would have been best to re-calibrate anyway when fitting new injectors.
Simon
I know they will be far more familiar with Yank stuff, but not sure if they'd balk at the thought of rebuilding a German autobox.
Reckon you'd probably only really need 3rd gear on a 3spd auto in most muscle cars, top speed only maybe 110mph in 3rd due to gearing even then. I used to love the Hill St Blues opening scene with a line of police cars all burning rubber out of the station, smoking tyres in every gear. My mate used to reckon he had the fastest car in town until I took him out in my Cosworth years ago... but he told me about the time he tried to race a TransAm from the lights...#
I've converted plenty 500ci engines, plenty torque in them!
Simon
Hate to say it but there might be more info on an American website.. In the UK autoboxes are considered a black art but in the US many home mechanics will have a crack at rebuilding them, probably because the info on autoboxes is much more readily available, there are chain stores of autobox rebuilding firms etc... just pop into a shop any buy a rebuild kit for a gearbox. I've delved into building them myself but it's a lot of faff and there are very specific tolerances.
Simon
With the injectors you've got I'd expect optimal pressure to be between 1 bar and 1.1 bar, but the installer probably left pressure set at the Bigas standard of 1.2 bar.
3mm Nozzles will flow 1.44x as much gas as 2.5 nozzles, since even V30 injectors will be working within spec at 4.5ms I would set pressure at 1..6 bar and adjust from there if necessary... but 1.6bar will work and the Bigas twin reducer will go to above that pressure.
Calibration will need a tweak anyway following fitting different LPG injectors, especially of a different type with a smaller nozzle size. If you left the old LPG injectors in place and they were working OK, fuel trims while running on LPG wouldn't be effected by changing petrol injectors - though it is possible to cause problems if fuel trims are very different when running on LPG versus running on petrol. I've never tried to look up info on specs of P38 injectors versus K series injectors, they'd have to be a fair match for petrol trims to be anything like correct when running on petrol and tbh I think they won't be that far wrong.
Simon
Yes it will mean 3mm nozzles.
In which case you could still fit Valtek type 30 rails but would need to increase reducer pressure and do a full recalibration. There are two allen sockets, one on each side of the reducer, alternate adjusting them in turn while watching pressure readings in software because you want them both to be fairly equally matched. If pressure from the individual reducers isn't well matched what happens is one reducer does all the work until it can flow no more (when you put your foot down) and then actual pressure suddenly falls to the setting of the lower pressure reducer.
The V30s are still a decent bet for a cheap no hassle fix because they're available with outlets to suit 4mm pipe (Bigas has 4mm outlets) and have very similar open/close time characteristics to Bigas. If your Bigas injectors had 2.5 stamped on them you could probably have got away with doing a straight swap without even connecting a computer and it would run at least as well as with the old injectors. .
Not all types of Bigas injector are available anymore (I still have some working ones of each type but they're old), the V30s are a better match for your Bigas injectors than the newer type Bigas injectors. New type Bigas are £100+vat for 4, you need 8, V30s are £35 including VAT for 4 but you will need to add a combined inline temp sensor / pressure T (easily fitted into piping) which is about £10 and will need the interface to recalibrate.
Simon
Orangebean wrote:
Now this is where the current job has the potential to get silly. Idly sitting planning my day- the thought creeps in...
" Really should drop the sump to clean all the crap out. When the sump's off and heads off it would be really easy to pop the pistons out and re-ring them, and of course with conrods out a new set of big end shells would be great preventative maintenance. If I did big ends, may as well do mains".
I'm my own worst enemy sometimes!
Might as well take the block out at that stage too OB, re-hone the bores, gearbox rebuild etc.. lol
RutlandRover wrote:
I think other elements of the car need information/signals from the engine to keep working too - like the gearbox. If you remove the engine from the equation I think it gives you problems elsewhere.
You'll know more about that than me, I know the gearbox needs TPS signal but that might easily be addressed, I've made a TPS up for catb'd Fiat Ducato's before just so the LPG mixer system could read it. Unless the gearbox ECU gets TPS from engine ECU over canbus?
Simon
I'll check out all your links later when I've a bit more time... fag break during the hailstorm! The 6x6 I saw would have been in the mid 80s.
Can see all your points and not intending a wind-up, just curious. On the immobiliser point was thinking along the lines of just sticking a carb'd V8 in, no engine ECU to need to talk to other ECUs, with a mixer LPG system off you go... or does the immobiliser prevent BCM stuff working too?
Half expected replies to bring up the weight difference, no problem there? How would costs involved with fixing up a Rover engine to prevent cooling / HG issues compare to picking up a small block from a scrappies and putting it in? Thinking the small block doesn't have the same problems and once fitted would open up the full world of tuning goodies available for what is probably the most modded engine ever with more torque / power from the off anyway, and you've got something a bit different / more powerful that might be worth more money when you sell it on..
Would think possible to fit a wide range of engines if the work was put in but to keep it simple use a carb v8 and one where parts to mate to the gearbox are already available. My mate fitted the engine from a Lexus400 into his Capri, expect that will have taken more shoehorning and involved with the electronics.
Simon
Don't ban me for this lol, I mention it out of interest - Has anyone suffering combined major engine problems and immobiliser / ECU type problems considered fitting a completely different engine altogether? As a kid I regularly saw a super long wheelbase Classic 6x6 Rangerover, it had an all iron small block V8 instead of the Rover V8, probably a Chevy motor..
Simon
There is no internal pressure balancing on your Bigas double reducer.
2 In 2 out filters can be used for pressure balancing. Your Bigas setup will use 10mm vapour pipe, though, not 12mm. 12mm is the standard size for filters etc..
Highly likely that your Bigas injectors are worn. Valtek type30 are a good match provided nozzle sizes on Bigas are 2.5mm or less. Don't strip your Bigas injectors to measure nozzle size, on those injectors the degree of nozzle tightening affects injector response and rails are calibrated at Bigas, removing the nozzles ruins the injectors.
Not sure if LPGshop will know much about the Bigas twin reducer, very likely they would phone me to ask anything they didn't know about it.
TinleyTech was the long time importer of that reducer, and injectors.
Simon
Pics of the general leak position below, though I could only just about see the actual leak. It's about as far forward as the rear airspring and just in from the chassis, I removed the wheel arch liner to see if I could get a better view from that angle. While under the P38 I noticed all the brake pipes look shot, I didn't check when it passed the MOT but it must have been borderline then. The only thing I did to cause the leak was press the brake pedal fairly hard while holding just above idle rpm in drive while stationery (useful to do as early part of calibration), probably just as well the leak happened under those conditions than while customer's wife was driving it.
I knew I had a busy day with about 5 customers coming including the owner of the Elgrand I just converted coming to collect it, another Elgrand owner coming for a chat and 'East Coast Customs' owner bringing his Jeep back from Hull hat I swapped the front end on maybe 6 months ago. Off topic but the Jeep was fixed in 5 minutes, just as I predicted from what he'd told me on the phone the problem was just a bad system earth.
So I copped out of fixing the leak and decided to let my mate at Joe's Garage sort it lol. Joe's only half a mile away and East Coast Customs guy didn't mind following me through as I drove the P38 trying not to use the foot brake, brought me back and I fixed the Jeep. Joe didn't get to look at the P38 until 5pm, then called me to say 'I cant fix this mate, cant even get to where the leak was but I pulled on the pipe and the broken bit just came off so I crimped it up to slow the leak'. Joe came and picked me up and I drove the P38 back to mine. I've called Simons Services, a Landrover specialist in Normanton WYorks who I've done a lot of work for before.. He'll definitely be able to fix it but I'll leave that up to the owner. I've emailed the owner, don't have their phone number (maybe because I recently got a new phone when old one broke and last synchronised old phone numbers years ago), explained all this, I await their reply!
Pics. The screwdriver is there to mark the position of the leak.
Simon
Thank you both Gilbert and Marty.
Got some paperwork and final check of calibration to do on the Nissan Elgrand I just converted and then hopefully I'll be able to get onto it..
Cheers, I'll keep you posted.
Simon