Ulysses

Good job matey!

Cinderella will go to the Ball

Been a bit of a while since I updated the thread. 

The trip out with Brett and Dave was great and a much needed day out. Then this week the MOT was due...

 

Fails on the emissions spectacularly . It was reading so high on their tester that it was almost off the scale. They think the cat in the exhaust has collapsed so I've brought it back home to get it off for a look. Its also overfuelling at idle (or there is too much unburnt fuel in exhaust) so I need to look at the ecu mapping a bit more carefully. Booked back in saturday for a retest so hopefully I can do something about it before then. 

Have you had any head gasket issues? Coolant can take out lambda sensors and make it run very rich.

wrote:

Have you had any head gasket issues? Coolant can take out lambda sensors and make it run very rich.

Hi Les,

Nah, the head and cooling is fine. Its just not that simple with Ulysses. The factory ecu is gone and replaced with a DTAfast S80 ecu to run the individual bike throttle body setup on the M18vvt engine. Most of the sensors are there apart from anything in the exhaust now, so the ecu doesnt do any fuel trimming based on lambda.

The map it runs was setup on a rolling road by a very clever fella, but needs a bit of looking at 2 years later really. I will ask about putting a o2 sensor in the exhaust as the ecu should be able to support it. I think there was a reason why not to use one, though I cant remember what it was...

The cat in my home made exhaust is steel cased and looks pretty sorry for itself on the outside, so I imagine the internals are past it by now too. The MOT guys were suggesting it might have collapsed and be doing nothing now.

O hang on... I think I've just figured it out after re-reading above...

A while ago I changed the sensor scaling for the coolant temp as the one it was on was calibrated much higher than it should have been (after comparing with a thermometer).

I wonder if thats meaning its always running on the cold start side of the ecu mapping, which is set to be rich to keep it from stalling. That would explain why its vastly different to last years MOT at the same garage with the same car.