High Emissions

[Lensteruk]

Grateful for some advice, I have a 92 Elan M100 1.6 Turbo which has just been for an MOT and I cannot seem to get the CO emissions down past 7.

She has been in storage for about 8 months and started regularly but not driven for a while. Initial start had a bit of white smoke and smelling of fuel from the exhaust. A long run at 70MPH on the advice of SJ Sportscars cleared up the white smoke but the emissions are still high. So far I have changed the plug leads, plugs, coolant, tried adjusting the mixture, put it in maintenance mode and adjusted the CO pot and ran elanscan (files attached).

The engine starts immediately and runs well on the drive, but at idle there is a very slight misfire every 2 seconds (ish) this is barely noticeable. The exhaust rear pipe has a very small leak also.

The elanscan attached has two files both the ECU and XLS in the zip folder. The car was run from cold up to fan start (they kicked in at 112 degrees C on elanscan and 3/4 on the car dash temp guage)

From here I have been advised to change the engine temp sensor and told that is isn't the static timing as a result of the hydrocarbon levels being relatively low. However, wanted a bit more advice to get through the MOT before I go spending out large amounts.. grateful for any steers...

[Simon_P]

First 3 things I notice.
1. you have a CAS Fault showing
2. It looks like you have a vacuum leak - IAC showing 10 at idle - should be 20
3. You need to fix the leak in the exhaust pipe it can affect the readings (usually lambda as it lets oxygen in)

[Simon_P]

From here I have been advised to change the engine temp sensor and told that is isn't the static timing as a result of the hydrocarbon levels being relatively low.

This is your fist post on LEC (welcome) where is here please?
From the scan the CTS output looks ok so presume you have already changed it.

Also
You can't "adjust the mixture" what did you adjust please?
The CO pot is not something that you are likely to need to adjust did you put it back to the original position?
Base timing is set dynamically - The concept of static timing doesn't really apply. There is no harm in checking it to confirm that it is OK.

[Lensteruk]

Awesome. Thanks so much for such a quick response. In answer to your questions. My local garage made some adjustments which were made on the manifold by the injectors and the co pot screw. I was planning to return the co screw back to original by checking the voltage reported by elan scan ? Is this correct ?

As for the leak. I will start to check the cause of this If you have any advice it would be appreciated. Whilst I am an experienced engineer - most of my experience is with aircraft and although I know my way around an engine in principle. I am not familiar with the lotus (Isuzu) engine.

Oh and here. Is sunny Devon in UK.

[Lensteruk]

As for the CAS - is that a case of checking the Hall effect sensor ?

[John_W]

Welcome!

I can’t read the Elanscan file ‘cos I don’t have a PC, so can you tell us what chip you have (it’s one of the first parameters you get in Elanscan)? Make sure it isn’t an old one designed for old emission laws; there was a replacement chip available.

For some info on the CO pot and chip see viewtopic.php?f=37&t=22116 . There used to be lots more info on the subjects but many threads have mysteriously gone missing over the years.

As to your question about the CAS, you’ll have to read the code from the Elanscan log and look it up HERE so that you know where to look for a fix if one is needed.

If you have a SE (as opposed to an S2) the CO pot substitutes for a lambda sensor (ie you don’t have a sensor) but you’d better get your exhaust leak fixed anyway.

John

[Lensteruk]

Hi John

Great thanks for that. My chip is a 9929 so that’s the starting point. Look for leaks and reset the co pot and repair the exhaust ! Gonna be busy ! That’s before sorting the CAS error.

[John_W]

If you still have the old 9929 fitted, you’re on a loser with emissions. You can adjust the CO pot to minimum and it still would probably fail. You need to get a 9930 chip, either from Lotus or an Elanchips upgrade, and trim the CO pot to suit. The 9929 should have been replaced years ago by a dealer.

[Brit-Car-Nut]

If you can't arrange for Lotus to sell you one (they require a deposit of around £100.00 until you return your original memcal) You can try Sjs as they have the A100E0097S which is the 9930 replacement chip for £62.91 but they don't mention the deposit. This is the current part number and price from Lotus for the emission correction memcal replacing the 9929 and the 9239 memcals. If you can find another 9929 or 9239 memcal cheap and can send it to me, I can re-program it to the 9930 code and send it back to you for the price of return postage.

If a group of owners want their 9929 / 9239 memcals reprogrammed to the 9930 spec, get together and send me the original memcals in one box and I will re-program them and I would just charge the price for return postage. Maybe if you get through the summer and are putting the M100 to bed for the winter, you could do that then as it will take a week in travel each direction. I can also provide the Moates type replacement kit like Alan, but I don't want to step on his toes as he did the original research on the Mountain Chip series. I WILL ONLY reprogram memcals with the Lotus original programs, but I have the all of the programs for everything from the NA to the S2 and the Calif FED chip I believe I even have the program for the Japan version too.

I am not trying to take over Alan's business and I don't have the Everest programs just for that reason.

It only takes a few minutes to reprogram and verify a memcal, but the postal systems involved are not exceptionally expedient.

[John_W]

... the postal systems involved are not exceptionally expedient.

I thought Americans didn’t do understatement!

[Simon_P]

... the postal systems involved are not exceptionally expedient.

I thought Americans didn’t do understatement!

On the contrary! The Don redefined US understatement yesterday when he described Jezza (Corbyn) as "somewhat of a negative force" ...when somewhat of an inept prat would have sufficed.