Wee bump on this... How are others fairing?

Since my last post, i've not actually used LPG at all. My local asda has removed its LPG tanks. The Morrisons about 10miles away (and any other nearby stations) are now 129.9p and is often out of stock. At that price, i think its acutally cheaper running on petrol due to the LPG efficiency drop...!

The only sticking point is the MOT. Its due this month and i suspect its going to fail on emissions, the LPG always gives it some extra wiggle room. Contemplating a 30mile drive to Dundee to get some LPG just to put it thru the MOT on gas....

I had this same fault code on mine after i converted it to Wabco D. However its gone away and hasnt returned all summer. I do wonder if it was dampness/moisture in/around the ECU unit as my car does seem to have a bit of a leak, and the ECU and area around it did appear to have sort of a slight sheen of condensation... It was also popping a few other codes relating to the pump iirc.

Lpgc wrote:

A warm engine is easier to crank than a cold engine, so if it cranks easier when cold it points to something else starter motor / electrics related being negatively affected by warm temperatures.

I wondered about this... and couldnt quite reach a conclusion...

Taken in isolation...

On a cold engine all the clearances are loose, theres probably a bit less compression as a result, certainly less friction. The oil is cold and thick, but at the point of turning the key the oil isnt really moving anyway, and it'll take a good few revolutions to get the oil pumping.

On a hot engine, everything expands, bearing and piston clearances close up, tighter ring seal, more compression, but the oil will be hot and thinner.

A hot engine typically starts easier, because theres more compression and the fuel ignites easier. However that requires the starter to be able to actually turn the engine and overcome that higher compression.

So i think i my best theory is that on balance, a hot engine is harder to crank but easier to start? IE it needs more torque from the starter to actually get it turning, but will light off easier once it is actually turning.

Not done anything with it yet, but had it out for a long drive at the weekend for a sort-of green-laning day...

1hr 30 of a/b roads, stopped at the meeting point for 30minutes. Wouldnt start, jsut a single wuuuuuuub and then nothing. Jump started fine from my spare battery. Then did some 2hours of laning, stopping at the top of a mountain for lunch. Maybe 45mins stopped, but i opened the bonnet to get some nice cooling air thru it. Started fine. Then drove down a 1000ft descent, 1st low, car didnt like that much and was billowing oil smoke by the time i got to the bottom. Shut it off for maybe 20minutes while others descended, started fine. Back up the 1000ft climb and along 15-20minutes of tracks, stopped again to wait on the rest of the cars for maybe 10minutes, and again it started fine. another 2 hours offroad, before finally stopping at a petrol station, and again, it restarted fine. So one failed start amongst half a dozen.

Really puzzling!

Thanks.

I will see if my spare engine has the starter attached and see about swapping it over.

Looking for some pointers.

The battery in the car isn't the healthiest, so sometimes can crank a bit slowly. However I've noticed a bit of a pattern forming where it really struggles to start when hot.

For instance today it fired up perfectly happily from cold, drove for an hour and stopped at a park and ride in town. Offloaded the kid, got back in to start it and got one crank and everything dimmed out... Tried again and it started.

On the way home, fired right up from cold, 30mins of traffic to the same park and ride, and again same thing. One or two very slow cranks with every thing dimmed out. This time I tried 3 times and still it wouldn't start. Grabbed my jump box from the boot and attached that and got one slow crank then a few much faster cranks and it fired up.

What I'm not sure is if the engines simply harder to turn when hot, and my battery is just not upto it, or if maybe the starter itself gets unhappy when it's hot?!

P0155 is a "heater not working" code
P0154 is a "lamdba sensor no activity" code

Both for bank 2.

So those indicate Bank2 lambda is kaput

P0135 is the heater for bank 1.

Probably time to treat it to a nice pair of new sensors then!

you can try shiply.com, they put the job out to tender and you get folks who travel all around that can bring it to you.

Worth bearing in mind the ECU can only see sensor inputs and act on that data.

The lambdas are giving feedback about fuel mixture.

What you currently dont know, is if the feedback is correct, and the engine is actually lean, or if the feedback is incorrect because the sensor is faulty.

I may ofcourse be teaching granny to suck eggs here, but as an example, imagine the MAF is underreading (either because its faulty, or becuase a split gasket or hose is letting some air skip past the MAF), the ECU is told there is 30g/s of air when there is actually 40g. It injects fuel for 30g, the engine is super lean, lambda detects this and ecu starts increasing fuel trims trying to fix it. Eventually it reaches the trim limit because if its having to add 33% fuel theres clearly an issue, so gives a system lean fault code.

In this situation, the lambdas are completely fine and are working as expected, the fault is with the MAF(or the air leak). But the ECU hasnt mentioned the MAF, because the MAF readings are close enough to what it expects that it hasnt realised they're wrong. Folks jump in with the parts cannon and fit new lambda sensors, and then are confused when the code remains.

I'm not saying its not the lambdas, just that care is required that you dont end up lead down a path.

It could be an air leak, fuelling issue, sensor issue etc. Try to be methodical, check the basics first, vacuum leaks and whatnot.

Given its at light load, that does to me nudge towards a possible air leak, as they tend to be fairly fixed volume and thus affect low load much more than high load.

yeah last few times i've used my big shifter spanner and just whacked it with a hammer.

This time i was probably not helped by the belt being covered in PAS fluid so it was probably slipping more than usual... I also couldnt remember what way i'm supposed to hit the thing, tried both ways. And with nothing to counterhold it was just not budging.

Tackled this on sunday.

I couldnt get the fan off (hate those damn things, i wish they would provide a decent locking mechanism!) which no doubt made it harder, but the main issue was actually the engine oil cooler hard line. The pipe couldnt move over to clear the box due to that line, and it couldnt move forwards due to the gearbox oil cooler line. I couldnt undo the gearbox cooler line as the whole rad frame was just moving around, it seems to be rubber mounted, and the thread in the gearbox cooler was proper stuck.

Once the engine oil cooler line was out the way, i managed to wiggle the pipes thru the tiny gap. Annoyingly i spent half an hour carefully painting up the new pipes to hopefully help them last a bit longer, and scraped them all up shoving them back thru the tiny gap.

Not a pleasant job, mainly because of oil pouring everywhere, and the whole underside of the car being covered in oil too. I think the gearbox oil cooler is also leaking, and no doubt the engine is too. Everything between the radiator and gearbox is just absolutely covered in oil.

My PAS lines have sprung a leak, thankfully only the return line, but the supply line doesnt look far behind, its extremely rusty. I've ordered a good used set off ebay as it appears getting new ones is near impossible now (especially for the supply line).

Is there any useful tips or tricks for fitting these? Am i going to have to pull out the fan and rad shroud? Or is it possible to get them out without?

I seem to recall that if the timer relay has been replaced with a standard one, it can stop OBD working.

Gilbertd wrote:

It does seem a bit odd. 255 is, or should be, the width in millimetres so that is what they all should be, although looking here https://tiresize.com/calculator/, the width doesn't appear to be the tread width but the sidewall width at their widest point. The red one I've recently got has 255/55 x 19 Goodyear Wranglers on it and the tread width on those measures 250mm but the sidewalls don't 'bulge' out beyond the tread by much at all and at the widest point would be around 255mm.

My car is on 7" x 16" wheels with 235/70 x 16 Kleber all season tyres, (which is usually a Disco or base model P38 size and that was what plod specified when it was new) and they measure around 210mm across the tread but 235mm at the widest point of the sidewall.

I'll try and measure the sidewalls, but that could well be it. Still a bit crap that these tyres pinch in so much giving you much less tread on the ground.

Indeed, For a more aggressive offroad setup i'd want to go larger 31-32" sort of range, and i had seriously considered some 255/70r18's from the new defender which are about 32", but once you get that far, there are certainly repercussions for EAS. I've seen folk recommend carrying some 2x4 offcuts to pack the bumpstops with in case of emergency, as the car wont roll on the bump stops.

The 30" tyre however isnt an issue at all. Its pretty much bolt on. Infact the rear was sat on the bump stops while i was installing them as the car was parked on a slope and it had let all the air out trying to level itself. Plenty of room.

My spare wheel well is filled with an LPG tank, so thats not really a consideration, though i have read slightly larger tyres will fit (sometimes only once deflated).

The V8 oil cooler will get a draw from the main engine fan, so essentially its always got airflow.

Most modern autos have a coolant loop in the main engine radiator. I'd say its rare to find an auto without a cooler!

Leaving it running really depends on wether the system has a sensible thermostat, if you over cool the oil the transmission wont like it. I know mine doesnt lock the converter when cold for instance. I'm usually a few miles up the dual carriageway before the gearbox oil finally reaches whatever temperature it wants, and you hear the RPM's drop as the converter locks up.

Perhaps you can find a good used switch instead of spending £100+ on a new one?

My P38 has been wearing some 19" L320 wheels for the past 5 years, shod with 255/50r19 Michelin Pilot Sport 4's. Obviously a full "on road" high performance tyre. but not so suited for off road use.

I've decided to change things up a bit, so i've bought a set of 18" L322 "twin spoke" wheels (https://www.landyzone.co.uk/attachments/img_1080-medium-jpg.43591/) and was on the hunt for some all terrains. I also wanted to go up a little to a 30" tyre rather than a 29". 255/60r18 would have been the original fitment on these wheels on the L322, and measures in at 30", so i decided on that size.

I decided after much searching, on a set of Continental Cross Contact LX2's, in 255/60r18. Mostly because i managed to find a used set for sensible money (bit over £200 for a pair with 7.5mm and a pair with 6mm). I initially wanted something a little more aggressive like the Michelin Latitude Cross, but i couldnt find any. I was also looking at the likes of the Grabber AT3 and Toyo Open Country AT's but i felt on balance it was probably still going to see a lot of road miles. And i also couldnt find any of those used either. On reflection, this tyre size is a bit niche/rare. I would probably have been better going with 265/60r18.

Anyway thats the back story. The tyres got fitted to the wheels midweek and i set about fitting them today. When i removed the first wheel from the car something immediately struck me, the tread on the Continentals was much narrower than the Michelins.

So much so, I went and got a tape measure...

The 255/50r19 Michelin measured about 240mm across the tread,
The 255/60r18 Continental measured about 210mm.

For reference i then measured a couple other set of tyres that happened to be nearby:

255/45r20 measured about 240mm (and these are also Continentals, but a road tyre)
235/55r19 measured about 210mm (winters)
235/40r18 measured about 210mm (Goodyear Eagle F1's)

So the continentals are certainly the odd one out here, despite claiming to be a "255" they're measuring up like a ~235 tyre.

Anyone else seen anything like this? Anyone fancy sticking a tape over their 255's to get some more data points here?

Not really sure what i can do about it at his point ofcourse, short of spending even more money buying some other tyres. But i'm intrigued to see if this is a particular quirk of these Continentals or maybe an "all terrain" thing?

the slope shouldnt really matter, at least as far as the calibration goes, as you lower the car down onto the blocks. So long as its not sufficiently uneven that it wont sit down on all four blocks.

The factory alignment/calibration uses a dowel that sits between the axle and bump stop pad.

The figures in nanocom will vary, which is why there is a mechanical alignment device.

You install the mechanical dowel, lower the car onto it, then tell the ECU that the measured height is now "correct" and it saves the current readings.

Thus if you want to check the calibration, the measurement between the axle and bump stop mount is what you want to measure/compare.

What were your CO and lambda figures when it passed?

The filter is before the MAF, a leak there really shouldnt affect anything? the MAF still measures all the airflow?

Keep an eye on your long term trims and see if anything creeps back in.

What you now need to figure out is wether its fixed, or wether the issue was somewhere else, like within the LPG system, or a bad sensor causing the fuel trims to drift.

Christopher wrote:

What I failed to mention in my original post earlier, was that fully serviced, tested and reassembled, it is sitting on its bump stops - full tank of air, ride height sensors in range - and when I switch on the ignition all the air is lost.
This has me completely mystified

So your saying you turn on the ignition, and it dumps the entire tank out the exhaust port?