Oulton and 5.5k rpm

Hi all,

It was good to meet you lot at Oulton, good circuit apart from zero grip and far to many accidents! I heard that an Exige hit the tyre walls, anyone here?

Anyway top day and should have stayed as it ended up taking me 8 hours to get home!!! Ouch!

So this 5.5k limit thing, the concensus seems to be the wheel speed sensor on the drivers side…

Can anyone offer a reason as to why it even exists? AFAIU, if there’s no signal then the engine misfires at 5.5k and then the car goes into limp home mode, is that it? Can these get f**ked? First and second it seems good…

Finally, is there a fuse for the stack? I seem to have gone dead there (my own fault )

Oh and one more, the main earth for all these sensors pumps, sender blah is in the engine bay towards the bottom isn’t it? I was gonna try and get to it and see if everything is attached OK

Laters,
Mark

Can anyone offer a reason as to why it even exists?

I think its there so that the ECU gets a wheel speed input when you are on trailing throttle and so cuts the fuelling to the engine…as opposed to zero wheel speed = parked and therefore engine is in idle mode.

The joint is on the rear offside wishbone - trying taking it apart and cleaning the metal contacts…its not really waterproof and gets gunked up.

Mark,

Reckon you should change the wording on you cool photoshop image to read…

At 5,500 revs you can hear Lima scream!

Sorry mate, couldnt resist!

8 hours to get back, You should have stayed for the curry to miss the traffic

Is it the whole stack thats stopped or just the speedo?
My Elise speedo stopped and it was the just the connector to the wheel sensor on the Passenger side rear! Have a look.

Hope you get it all sorted

Paul

RL

Nice to meet you on Friday…I’m gonna have to go against concensus at this stage…I don’t think your problem is anything to do with the wheel speed sensor. If you don’t have the recall’d ecu this sensor won’t give you mis-fires or 5500 stutters. My guess at the moment would be that you have already got the recall’d ECU change ?? and you have a genuine mis-fire - maybe leads tracking under load, or dodgy plug or lazy injector?. I forgot to ask you or have a look at your car on Friday but have you still got standard ignition leads? Were you getting the mis-fire on Friday at Oulton after you disconnected the wheelspeed sensor?? My guess is Yes ??.. proves nowt IMO

I think this sensor is only there to allow fuel cut-off on the over-run as mentioned by Steve above. Do a search on this site for ecu recall… IIRC there is a big explanation of how disconnecting this sensor can lead to a mis-fire and the new software will rev-limit to 5500 and you can limp home… this is to protect the cat from getting its tail burnt.

However, I think you need to look for a genuine mis-fire.

I think fuse 8 in the front compartment fuse-box is for the instrument binacle.

I know why you’d want to check for bad earths… from your recent experience,… but I doubt the main earthing will be your problem… this would lead to all manner of weird and wonderful electrics problems.

Anyway, I’m a lay-man but I hope you get it sorted. Keep us up to date… awerabest

Cheers Paul & Rox,

LOL! I think I’ll have my Desktop as “at 5.5k, you hear Mark scream “F**KING LIMITER!!!””

You could be onto something there tho’ Rox, over the weekend cylinder 1 intermittently stopped firing, I managed to get home but it really tested my heel toe as it just wanted to stall all the time! Then a nice sulphur smell from the cat & black carbon all over the exhaust! Yummy!

Are the origional leads supposed to be poo? Magnecore’s right? (I never liked them in my SC, or more to the point, my SC never liked them )… Also need to get the S2 cam cover really, is there anywhere I can get both?

Got the fuse I blew but now have my head unit working (ISO is so easy!), I could have really done with that on the 8 hour journey home! Phone ran out of batteries as well so no radio

Thanks again,

I assume the curry was good?
Mark

RemarkL

Sounds like yer cat isn’t too happy??..

The original ignition leads are fine but if you decide to replace them then its a pretty standard upgrade to go to Magnecor Reds… Eliseparts and Racespeed sell them for around the going rate - the S2 cam-cover is a Lotus Dealer only part… but the good news is it only costs aboout �12… Pesky or IDG could confirm this.

What fuse was it that was blown?

keep us posted on how you get to the bottom of your mis-fire problem.

cheers and good luck

Mark

Read my comments about the eventual cure to my red hot exhaust manifold pipe problem…

The imbalance caused a slight misfire, so that could also be a contributing cause, perhaps ??

Read HERE