Noticed in today's heat and whilst sitting idling on the M25 that the AFR has gone from cycling about 14.7 to 15.5 in fact the reading looks to be on the lean side across the range. Didn't try WOT just in case.

The meter's the Innovate stand alone gauge kit and has always given readings at about what you'd (or I'd) expect.

Could the hot weather cause lean running?

I'll try to re-calibrate it on air tomorrow and see how it looks, after trying it again first.

Another thought, It was after filling with optimax (at 92.9p/ltr ) plus 1 bottle of Millers, previous to that fill it was on Tesco's 99 octane (86.9/ltr) with 2 bottles of O/B. Mapped in March by Andy F on Opti only. Just thought I'd play safe and add O/B for the hot weather.

Gerry.

 

Are you running closed loop off a narrowband sensor that is separate to your wideband kit then? If so, is it failing?

 

Hi John,
Thank you, I hadn't thought of that. Yes the wide band is for display only, at the moment. the narrow band is about 12 months old ~25K miles. The innovate has been in about 3 months.

I got the w/b from Zak @ Mocom racing and the last I heard from him, before his trip to Africa, he reckoned the Innovate could be wired into the Apexi ecu.

Being a lazy bugger I was hoping he'd get back to me with how to do it.

Is there a way to check the narrow band or has that already been done by the w/b? Bit of a dumb question really

Would you suggest re-calibrating the w/b or just replace the n/b sensor?

Thanks
Gerry

 

Actually I run my Power FC's closed loop control with the LM-1 using its NB simulation, setting the crossover point at AFR 15.2 for better crusing mileage, and to get rid of the NB sensor entirely. So far the sensor's life expectancy seems good enough (more than 12 months now, permanent use)

You might want to repeat the free-air calibration also since this might deviate with time. I do it every couple of months and every time I find it a bit off by not by much.

Robert

 

Oops! that should have read 'wired into the Datalogit box'

Sorry

 

Just an update for anyone who's interested.

When I next started the car it was very obvious that the exhaust was blowing somewhere around the turbo. Ended up at API where it was discovered that the two year old Gruppe-S headers & flexi up-pipe had begun to self destruct

The convoluted section in the up/p was split around the bellows and the headers, where the pipes from cyls. 2 & 4 meet the collector had failed, for very near as much as could be seen of the join. It looked as though the slip joint had stopped slipping and all the thermal movement was taken on the welds.

New headers & u/p fitted and AFRs are back to normal. Maybe it was drawing in air through the splits?

Gerry

 

the pulsing on idle will indeed suck in some air, it takes very little to upset the readings, so I think you found your culprit.

I saw your headers at API, and I have to agree with your postmortem, as it happens mine failed in EXACTLY the same place where the tubes meet the collector.

Paul

 

Mine also failed in the same place and were welded up along with the collector.

 

Ended up with a new set. When I saw the cracks to the headers, I couldn't see how they were welded 'inside', i.e. where the welds disappear. The up-pipe would have been more trouble than it was worth so junked the lot.

I'm now in Scotland for a weeks work so can't afford to take chances with the car.

Thanks for your comments.
Gerry