Lotus Elan Central

Before i incur the wrath of the 'Mighty Mods', i know this could have gone into ignition, exhaust, engine or elanscan sections - but i chose this one

Secondly, there is a similar thread (which I've now 'lost') which it could have gone onto, but the advise on there was to change the chip - and i already have!!!!

So, to start at the beginning, it failed the MOT as the CO emmissions were too high (4.1%), no matter which setting the switcher chip was on.

The CO pot would adjust the number upwards, but it would go no lower (I didn't do it, the garage did!).

No flashing of the CEL has occurred.

My questions are thus:-

Can you adjust the CO level with the engine in 'normal' run mode, or does it have to be in 'flashy-engine-light-on-the-dash--no-sensors-connected' mode??? (shorting out the 2 wires on the aldl plug).

How can i get it lower?

Should i cheat and induce a slight air leak if so, how and where

I plugged elanscan into the car, and it shows 2 x MAT (low) faults - is this my problem??

I plugged the laptop in with the car stationary, and just up to 'fans kicking in' temp - should this have an effect on the readings?

CTS???

I took it for a run round the block and got full throttle for the last blast up the hill, so the elanscan file *should* have a reasonable set of conditions demonstrated, even though it's only a 1 mile trip.

Any answers greatly appreciated (well, helpful ones, especially!)

PS - i don't have access to CO test kit at home, so any way of getting a rough indication??

dapinky wrote:
Should i cheat and induce a slight air leak if so, how and where

???...Remove the heater control vacuum pipe and adjust the revs to compensate... or for twice as much, the unused connection next to it, as well...???

Ray

Dave,

You need it in service mode ie with engine running to do the adjustment, i had plenty adjustment on mine when i had the peco fitted and set it at 3%:? Best to adjust it when it`s in for the MOT and they`ve got the probe up your hole you only need small adjustments, but give it a bit of time to register on the machine ie 30secs or so

Make sure you have fresh fuel in your car, mine failed its MOT 2 years ago with 9% CO due to the fuel having started to go off (Had been in the tank for 5 months)

Only one thing sticks out....... you're knocking faster than Dico's fantasy bird (tits like coconuts).

Back to first principals: Have you set the base timing?

He can be quite sensible at times... I agree, first off check base timing.

It aye called baaaaaase for nuthin'.

Odd how these things come round in groups - mine also failed at about 4.5%
It's been just under the 3% max for each of the previous 4 MOT's. Something has changed
No amount of adjusting the CO pot made any diff - is it true it needs to be in service mode for this or has my pot gone to ........?
Anyone have any experience with the 'Gunson' analyser you can get at Halfrauds for around £40? I'm thinking of getting one then I can correlate it with the known 4.55% before I start to fiddle about
Maybe closed loop is the way forward but I'd like to fix the problem first.

GeoffSmith wrote:Only one thing sticks out....... you're knocking faster than Dico's fantasy bird (tits like coconuts).

Back to first principals: Have you set the base timing?

Sy V wrote: He can be quite sensible at times... I agree, first off check base timing.

It aye called baaaaaase for nuthin'.

Oh, Come on!

What sort of Muppet do you think I am?
(if THAT doesn't elicit any replies, I'll be surprised )

It was the first thing I checked (after reading your replies)...............

After all, if 16 is good, then 22 MUST be at least 6 better



Surprisingly, with it set at 16btdc I ran elanscan and didn't register any knocks at all

I don't have a CO tester at home, and when i looked on the Halfrauds website, they want £75 for one!

As such, i'll take it back to the garage tomorrow and see how it looks.

Can anyone confirm Montys reply that the CO pot should be adjusted in service mode (as per the manual), and will it only have any effect if you do that, or should it still change the readings anyway??????

(I only ask so i know what to fiddle with if it is still too high - don't want to be paying any sort of hourly rate if it has no effect at all)

Why would posting a new thread in a relevant section incur anybody's wrath after you've obviously searched for the answer first?

I don't move these things around just to p!$$ people off you know!

You'll be surprised just how small a turn on the CO pot it takes to make a massive difference. And no, it doesn't need to be in service mode.

Oh, and my emissions had gone up this year too (0.65% last year, 1.55% this). But then, I took it in for it's MOT knowing I'd got a bad misfire, and swapping out a coil-pack fixed that. Maybe it's burning fuel more efficiently too now - I don't know.

I've got an analogue and a digital Gunson's Gastester.
You're welcome to borrow either if you can find someone who's passing by, but because they're fragile I wouldn't want to post them.

I checked last night Dave and it definitely says adjust in service mode then run the engine until the fans cycle before checking.

Oops, got that bit wrong then!

Enright wrote:I've got an analogue and a digital Gunson's Gastester.

Any idea how accurate they are? Any correlation with an MOT analyser?
Maybe a bit late tho' as the pot was messed with a lot during the MOT as 'we' didn't think about service mode

I'm prepared to fork out £40 - actually £43 at my local Halfrauds before I start to twiddle, if they are any good.

Hmm, I'll have to re-check it.
I reckon from memory you can get it accurate to within about 0.5% accuracy, which is OK for SE's, but next to useless for S2's. However, as long as you are able to get a consistent reading that you can work with, then they're not too bad.
But if I were you I'd have a look on eBay rather than paying full price because they're always coming up.

Well, i got a Gunsons Digital thingy and with the base timing set up properly, I got a reading of 3% CO.

Off for a re-test today - CO = 2.98%, but Hydrocarbons = 2577ppm (1200 is upper limit).

A bit of a misfire and clouds of white smoke

HGF again

I had a choice of doing just the HG, or swapping the engine for the spare one on the drive.

Monty wrote:Far easyer to do the head gasket than swapping engines Go for the Lotus HG this time

I never like doing it the easy way though

Besides which, i was intending to do the swap this year at some time, then fully re-build the current (now knackered) engine before putting it back again!! It was starting to use oil, and with 135K on the clock, the bottom end could do with a going over.

I fully intend to use Lotus HG next time!!!!

Hence, I spent the afternoon waving a selection of spanners around under where the bonnet would have been if i hadn't removed it!!!!

Everything is disconected at the top - just got to get to the driveshafts now - then undo the positive cable to the starter/altenator then it's a quick lift and swap.

Only one question at this stage - how do i remove the speedo drive?? the big nut turns by hand, but is it attached to the cable (mine seems to be quite solid) or should it swivel??

Perhaps a kind Mod would move this thread into the Projects section, where it probably now belongs, being a 'work in progress'

dapinky wrote:Perhaps a kind Mod

Oxymoronic or R'slicking?

...

Do you need to borrow my Engine hoist Dave?

Thanks for the offer, Phil, but i now have 2 large carboard boxes full of mechano-type bits which should 'home assemble' into one!!!

You've probably got the engine out by now Dave.
Sounds like your speedo cable has the retaining plate missing, coz you'd have spotted it otherwise? If so, its just suction thats holding it in place. Give it a good tug to release it.
btw, its a blxxdy tight fit to get the engine out! (as you are probably aware by now)

Dico wrote:btw, its a blxxdy tight fit to get the engine out! (as you are probably aware by now)

It is when the gearbox is still attached