Coming along the M4 yesterday, when all of a sudden the check engine light came on.

Had been doing a constant 4000 rpm for about 90 minutes or so. Engine did not cut out, I slowed down by about 10mph and the light went off after about 5 minutes.

I've got a full SS exhaust system, and recently put a K&N 57i induction kit on. Also, not sure if this is relevant, I run on SUL and octane booster, and because I hadn't filled up a full tank before setting off, the octane level was probably up over (slightly) 100RON.

I did the same journey the day before, with no problems at all, although I did do 160 miles on half a tank - too lean?

Anybody got any ideas what the cause could be, and if I should be unduly worried, (BTW it is a UK MY99) - all commenst extremely welcome!

Matt

 

One possibility could be the crankshaft knock sensor.
A crypton tune would find the problem!!!

Hope this helps
Darren
If it comes on again put it in the garage for a check up

 

It is going in for 37500 service in a couple of weeks, so I'll get them to look then - just wanted to make sure is was OK to drive in the meantime.

 

Matt,
buy a new one

simon.

 

Matt

This will take your mind off the problem


Simon

 

PCB and Gobbo,

Thank you for your assistance, I take you two haven't got much work on at the moment!!

PCB, I think you've got your "cool" wave down to a tee now, after seeing you in the week - now all you need is a cool car

Matt

 

I'd be very interested to know what error code the ECU has logged in it memory
(See other threads for how to connect up the single pin black plus under the dash and turn on ignition
Should get a series of long then short flashes)
Then switch off ign and disconnect black plugs
(else the check engine light will stay on if you drive off)

I had almost exactly the same problem recently after driving relatively hard
code 24 = idle air solenoid

Been running fine since then
but haven't driven so hard again yet

Stephen