Superspec Ecu Analysis

[alanrichey]

I use a program called librosco (https://github.com/colinbourassa/librosco/releases/latest) that 'grabs' the output of the ECU, feed that to a text file and then wrote the analyser in Visual Basic.

Edited February 11, 2016 by alanrichey

[Kerry]

Hi Alan, looks like its keeping you busy.

[Al Milton]

Blimey Al, good piece of work.

But alas, my level of understanding is limited to black magic & witchcraft when it comes to software

[alanrichey]

Well, at least I know why my Superspec has struggled with the MOT emissions test. Here is a screen shot of the lambda voltage on a recent trip

 

 

and here is the same screenshot from someone running a Mini SPI with a Rover K Series engine

 

 

His is working correctly, rapidly cycling between 0V and 1.0V (This ECU works on the bang-bang principle switching between 2 fuel maps). Mine seems to work but after 2 mins just goes off in a sulk and stops working. Maybe when it warms up ?

 

I now need another Superspec owner to run a similar test to see if we are facing a design fault with the exhaust system or whether my lambda sensor is just knackered.

 

What fun

[sj-bradley]

I'd overheard a comment from another hoodie about the exhaust being "too" free flowing and when he had blocked off one of the outlet pipes and left just the one, the back pressure made the lambda sensor start working correctly.

 

Apparently, it needs a bit more back pressure to keep the exhaust hanging around the lambda long enough for it to read correctly. I wonder if you could baffle your exhaust somehow and see if it makes a change?

 

Simon.

[alanrichey]

Hi Simon. That was me at the end of season bash I had been told that and from a subjective viewpoint my car does seem to run a lot better with one of the exhaust outlets blocked, better MPG, better acceleration and no popping on the overrun, so I have left it blocked. Unfortunately, now I can accurately measure the lambda performance I can see it makes absolutely no difference in that area However, as it now looks as though my sensor is kaput, we still don't know if there is any truth behind the idea.

 

My biggest problem is a lack of information on how the MEMS 1.6 ECU actually works. So I am having to work on guesswork, hearsay, common sense and a small amount of genuine technical info. As I understand it so far, the ECU starts in Open Loop mode and uses the lambda sensor as I described before, to switch rapidly between 2 Fuel Maps, one a bit lean and one a bit rich, so the average is a perfect mixture. If it senses the lambda sensor is not working properly (like mine) it switches to Closed Loop mode and reverts to a default fuel map that should work reasonably well. So my car seems to be running permanently in Closed Loop, which is perfectly acceptable. The problem comes at MOT time when the emissions test sees the lambda is not working.

 

If anyone knows of any source of information about the MEMS 1.6 (not from the Internet I have drained that well dry), but perhaps from Rover garages/technicians, then I would be very grateful.

 

Al

[Guest 2b cruising]

Have you tried contacting the chap that worked for R H then went to Caterham on K series engines.

Can't think of his name but I know he did a few things both on the forum and on u tube.

Sorry about his name and thread name but I do remember seeing it.

[alanrichey]

Well before my time I'm afraid. Any idea for a Forum search word ?

[Guest 2b cruising]

Sorry Alan but no.

Someone does as they posted a link.

I believe he now tunes them for a business.

His link on here might have been for Pinto specs but he then moved on to K series very successfully.

PM Bob Tucker. He is very good at remembering things like that.

 

I am also quite sure it was in the last 12 months, I've only been a member for a little over that.

I hate getting old.

[ozz]

Sorry Alan but no.

Someone does as they posted a link.

I believe he now tunes them for a business.

His link on here might have been for Pinto specs but he then moved on to K series very successfully.

PM Bob Tucker. He is very good at remembering things like that.

 

I am also quite sure it was in the last 12 months, I've only been a member for a little over that.

I hate getting old.

Sounds like that might be Dave Andrews

 

http://www.dvandrews.co.uk/

 

)I don't know him but used his build blog for pinto stuff)

[Guest 2b cruising]

That's him Alan. Dave Andrews.

 

Thanks Ozz.

[Guest 2b cruising]

Lots and lots of interesting reading on his own site there.

It's a pity the prices go up year by year though.

If you could still buy at these prices, there would be a lot more fast kits on the road.

[Kerry]

I think you have a Lambda problem, is it showing resistance on the heater circuit?

[sj-bradley]

(I slept since then and forgot it was you ... )

 

I think you've got it the wrong way round. The engine will start in open loop mode until the engine temperature is high enough and then the closed loop mode is active which uses the lambda output to affect the engine one way or another.

 

If the lambda stays put, it may fall back to open loop mode.

 

Closed loop just means that the feedback loop from the sensor is closed, i.e the information is returned back to ECU which affects the exhaust which affects the sensor etc. Open loop just mean the ECU is having a best guess and not checking the lambda. Almost a limp home mode.

 

Simon.

[sj-bradley]

Have you also checked this page?

 

https://github.com/colinbourassa/memsgauge

 

I suppose you have also been here :-

http://alum.wpi.edu/~colinb/mems_interface.html

 

Simon.

Edited February 16, 2016 by Simon B