ive viewed the voltage and airflow with nanocom, and it seemed "sane".

At 2500rpm it gives the 60g/sec specified in the manual, What happens if i try to back the revs off though is peculiar. I can get it down to about 2000rpm. Once there, a tiny reduction in throttle will cause the RPM to fall, but then keep falling. I presume it gets too lean, which causes the engine to slow down, which causes it to get leaner, and it goes into a spiral that if left unchecked would result in a stall. To catch it you add a tiny bit more throttle, and it revs right back up to 2500rpm again.

So i THINK the MAF is fine. When it idled properly, before i started messing with the injectors, i'm sure it sat around 20g/sec at idle

From listening to the engine, it seems that the vacuum leak gets larger as the engine slows down, so i guess this makes sense, as more air will be coming in via the leak rather than via the MAF.

Oddly it still does this trait with the maf unplugged as well, but its easier to control and you can with very fine throttle control get it down to idle and it will then sit there.

yeh i guess your right enough. I just know theres very likely cylinder head or piston ring issues lurking as well, i just want to get it to a stage where it actually runs properly before i start down to road of properly diagnosing that.

I'll need to see whats involved in doing the valley gasket, i guess i'll need to drain all the coolant as well :/

As per the other thread, i've various running issues that i'm trying to resolve. If i'm going to replace parts, i tend to buy new, as then i know i can rule it out. However the MAF's are ludicrous money, so i've got a used one.

So i'm wondering if i can send my MAF to someone on here with a GEMS car that actually works, and swap it in and see if the MAF is actually working properly. That way i can rule it out as a possible issue!

Cheers.

The new injectors came with new o-rings, so ofcourse i used those, but they were 14.5mm, as obviously thats the standard size of orings used for the past 30 odd years. As usual rover decided it would be fun to do something different for no reason.

So, just took it all apart again, swapped the 15mm gems o-rings onto the new injectors, reassembled. Guess what? Exactly the fucking same.

Paying closer attention to my spraying, i think it might actually be the inlet manifold gasket thats leaking... spraying the joint between the manifold and head seems to make the engine rev up. But thats just insane, why on earth would that start leaking!?

I can see now why people warned me off these cars. I'm several weekends and probably a grand down, and i have a car thats more broken than when i bought it, and the more bits i fix, the more seems to go wrong.

Mine has no filter at all between the vaporiser and injectors. I dont know if theres one before the vaporiser, certainly nothing in the engine bay.

Right, spent some more time this morning banging my head off a wall. Tried it on LPG, didnt work, no better at all, so maybe its not a fuel pressure issue, or maybe the LPG is just broken as well.

Unplugged the maf, and got it running. Seems to act odd when first started without the MAF, you need to give it lots of throttle and really work hard to keep it alive, and after maybe 5-10 seconds it sorts itself out and starts running. I eventually got it to idle, by super-gently letting the throttle out. Initially it was surging up and down but eventually it settled to a rather unsteady idle. With it idling and me able to actually get out of the cab it became immediately obvious there was a vacuum leak. The hissing was so loud i could hear it from my garage 20 meters away clear as a whistle.

Grabbed a tin of brake cleaner and sprayed it over the number 1 injector as that seemed to be where the noise was coming from and the engine RPM's shot right up then the engine stalled. HMM!

So decided to pull the fuel rail out again (for what feels like about the 17th time) to try to see what was going on.

Discovered this:

https://www.dropbox.com/s/eqiuxgtvn62r6ij/2016-10-09%2011.41.46.jpg?dl=0

If you note the upper circlip groove position, you'll see that the Audi injectors (middle) have the groove a lot further down, and the new injectors at the bottom had both grooves. The lower groove means the injector sits further up into the fuel rail, and thus doesnt full engage with the manifold. When i fitted the new ones, i used the bottom groove, and thus those were also fitted incorrectly. So i swapped the injectors over to use the upper groove and reinstalled them. They fit much better in the manifold now, but having put it all back together and tried it, its still no better, and spraying the injectors with brake cleaner still causes the RPM's to shoot up. The hissing is quieter, but still there.

Its really stressing me out now.

Like i said, it ran fine before with the maf unplugged. The old one would crap out when it got hot. Unplugging it allowed the engine to run fine. It idled fine, drove fine, and (unintentionally) completed an MOT emissions test like that, albeit failing because it was rich. I only realised it was unplugged when i got home from the test!

I'm going to reconnect the missing LPG hoses in a bit, and see if it runs properly on LPG. If it does then it would seem to narrow the issue down to fuel delivery. However when trying LPG previously, when it did actually work(ish) on petrol, seemed to show one bank full rich and one bank full lean, which probably indicates an issue with the LPG system or injectors. I've noticed there appears to be no filter at all on the vapour side of the LPG. Might be one on the liquid side, but i cant see anything, so it wouldnt surprise me if the injectors are clogged up.

I reinstalled the plenum and trumpet thingy with silicone, but thats twice i've had the inlet of and reassembled, so it would be pretty bad going to have managed to screw up the sealant twice.

Theres two takeoffs on the manifold for the gas system, but the hose was melted so i've blanked them off for now. I Might try and hose the inlet manifold with WD40 tomorrow with the engine running and see if that makes any odds.

And again, if it was a vacuum leak, you'd expect it to run fine with the MAF unplugged, right? As the vac leak causes the MAF to read incorrectly, and if the MAF isnt there reporting the incorrect data, the engine will run normally.

Marty: The original maf was broken, it crapped out when it got hot. i've replaced it with a used one from ebay. I also tried unplugging it. When the old MAF was broken, the engine ran fine with the MAF unplugged. Infact it ran BETTER with the MAF unplugged. With the new MAF on, it ran fine, until i did the above work and reset the adaptions. Now, it wont even run properly with the MAF unplugged, as i tried that earlier. The MAF values reported by nanocom seem feasible, so i'm struggling to see it as a MAF issue.

The IAT values are odd, showing -3 i think on nanocom, but even with that, a low IAT should be enriching, and i'm pretty certain this is lean.

Gilbertd: when its running in proper closed loop, you can see the STFT's cycling up and down by a few % and the voltage swinging up and down. Lambdas act a bit like a switch, So the ECU slowly enriches the mixture until the lambda switches rich, and then slowly leans off until it switches lean. If its stuck at 38.75, it means its run out of adjustment and still hasnt managed to get the lambdas to switch. My lambda voltage stays low when the trims are stuck at 38.75. When i rev the engine up to 3200ish and it starts switching, it starts cycling between 1 and 5ish and the STFT's drop down into the high 20's. So whatever is going on, its running out of adjustment at lower enginespeeds, and cant compensate by enough to keep it running.

Your saying you get 5v and a rich smell. but your reporting +38.75? I'm getting a low voltage (it fluctuates a bit, usually 0.5-1ish) and no rich smell and +38.75. They cant both be true? I would expect -38.75 if it was rich?

Current thoughts are fuel pressure. Ordered a test guage. Really clutching at straws though. I've fitted new lambdas, so i can trust the readings, and they are both doing the same thing, which suggests whatever the fault is, its something global, rather than per-bank. I was considering pulling the wideband lambda out of my track car and grafting it in, but i really cant face trying to fit an sensor bung into a pipe under the car.

TBH i think resetting the adaptives is what caused this whole issue.

It ran ok, but was fouling 3 of the plugs on one bank. I suspected leaking injectors.

I replaced the injectors with some Gen2 Bosch parts i had already, fitted new lambdas another set of new plugs and reset the adaptions, and after that it wouldnt run worth a shit.

I thaught it was because i'd fitted injectors that were too large, bought the correct ones, and its exactly the same.

Clearly, adaptions should be clearable without issues like this, but i guess they were maybe masking some sort of underlying issue.

Ok, so it wasnt my fault after all.

Fitted the new, correct, smaller injectors, and guess what? Still wont fucking run.

I've literally NO idea what is wrong with it.

Start the engine from cold, it runs like a total sack of crap, give it lots of throttle and keep it running at 2-3krpm (lots of manipulating the throttle) until the lambdas come online (you can see it switch on nanocom) and you see the short term trims climb from 0 to 38.75, and as it does so the engine begins to run better. Unfortunately it then jams itself at 38.75 and just sits there.

If i get the revs up to 3000rpm, then you will see the sensors begin to switch, with the short term trims cycling in the high 20's, drop the revs down to 2000rpm and it goes streight back to 38.75 and the more you lower the revs the worse the engine runs. Its next to impossible to keep it running at 1000rpm.

I really need to understand what these trims mean. In my mind, a positive trim is the ECU ADDING fuel, suggesting the engine is running very lean, and is having wind the fuelling right up to try and compensate. That simply doesnt make sense, unless this long term trim of -160 really is subtracting huge amounts of fuel. If thats the case i simply cant see how i'm supposed to fix this? I cant get the LTFT's to come back up to 0 unless the engine will run and drive. I cant drive it if it wont idle, especially as it has an automatic trans...

yeh sorry, too used to VAG stuff that reports MAF in g/sec.

Readings were from nanocom. 20kg/hr holding the throttle open by enough to keep it at 1000rpm (as it wouldnt actually idle and was really lumpy even at 1000rpm), and 60kg/hr at 3000rpm.

MAF readings seemed perfect, circa 20g/sec at 1000rpm, and 60g/sec at 3000rpm.

Bloody cars. It wont adapt the LTFT unless its being driven either, and i cant fucking drive it without an MOT. What a stupid arse system.

Why on earth would the LTFT start at -160? That said, it was at -154 when i started, which isnt much better....

I'm still no wiser though, is +38.75 adding fuel or removing it?

As mentioned in the other thread, I fitted some new injectors as i had a feeling the old ones were broken. unfortunately i fked up the measurements, and fitted what are actually 245cc injectors instead of the original 200cc ones. Started the engine after resetting the adaptions and now it wont idle. rev it up, its fine. get it up to 3000rpm or so and the trim moves away from 38.75 and starts dropping down a bit. Drop the RPM's down and it just goes back to +38.75 and the lower the revs the worse it runs. By the time your down at 1000rpm its choking and farting and running like shit. Release the throttle pedal and it dies.

Given the injectors are too large, surely the fuel trim should be fully negative, as it should be trying to reduce the fuel...

Well its still broken. This time becuase i've cocked it up.

The injectors i swapped in i thaught were 210cc, which i figured was close enough to the required 200cc. Turns out, after looking up the actual specifications, they are 245cc. Which seems to be too large an error for the ECU to correct.

So, I found these:
https://www.fiveomotorsport.com/lucas-range-rover-gems-hotwire

Crossreffed the bosch part number here in the UK, and managed to find a set of 8, new, for less than the cost of getting the broken lucas ones cleaned.

More waiting.

Can anyone with a Nanocom or similar tell me what these engines display normally for their long term and short term fuel trim?

Can anyone also suggest what the device means by a "positive" trim?

In my mind, a positive trim = Adding fuel, but i'm not convinced thats correct given i've fitted slightly larger injectors yet the trim is jammed at 38.75 and the sensors are stuck around 1v.

Long term trim was showing at -154, which i thaught was way out of whack, so i reset the adaptions. But then it went to -160... surely reset should be 0?!

I know, hes being a bit of a cock, but hes also the most-decent MOT place around here. I've had a good few run-ins with some other places over much bigger issues (like failing the car for things that arent actually faulty...) and this guy seems fair and reliable. Last thing i want to do is cause issues for him.

And to be honest, its failing the test because its broken. Out of the four or five tests i've had it on, its only actually successfully completed one emissions test, and that was the test with the MAF unplugged that returned the 1.3% CO readings. The rest of the tests were stopped due to the car either dying, or chucking out so much unburnt fuel that the machine aborted the test.

In that state, LPG wouldnt have helped. I'm also unconvinced the LPG is actually working correctly, and would like it running properly on petrol before i start looking into the LPG issues.

yeh thats better :)

Cheers

Can we wind up the "threads per page" count? Usually its adjustable by user but this software doesnt seem to allow it. A few of the subforums have a pile of stickies at the top, which means you only see 4 or 5 threads before it reaches the end of the page. Similarly when viewing a long thread, it splits to a new page after only 10 posts which seems somewhat short...

yeh, i guess i'm going to have one last go with this place and see if i can get it thru the test. Looking at whats been happening, the High CO figures from above were due to the MAF being disconnected. The last test got aborted due to missfiring, which i presume was due to the fouled plugs. I'm hoping now, with fresh plugs, and hopefully non-leaky injectors, it'll pass.

If it was consistently failing with the same results, i'd be a bit annoyed, but every time its gone in, something different has happened.

If it fails again, i guess i'll need to find somewhere else that will let me test it on LPG. Which reminds me i need to buy some LPG hose, as i found a few melted bits that needs sorting.

yeh it'll warm up just fine, i just didnt finish putting it together. Need to fit the MAF/intake pipework and some other minor bits.

I'm going to try again to get an MOT on it now i've changed all those bits, as even if i'm going to have to pull the engine to bits, its FAR easier trying to diagnose things when you can actually drive the bloody thing on the road!