Robs7

Hi Tony I know it's a bit late but if I was going towards Hertford It was probably me as if there's is nothing on that road you can really test your skills. However it's only a 360r. If your around that way again and my car is outside the coach and horses pop in and I'll buy you a pint

Thanks Chris

Thought I kept the box but must have binned it so will check the new one. Can I adjust mixture myself or is that a specialist? Also I have not used any sealant on the primaries or collector.

Thanks I'll check all those points

I thought that but upon checking the box and compare with the old one it is genuine. the supplier is sending a new one under warranty.

Well guys after 5 weeks and approx 400 miles the same problem has occurred. Looks like it's the lambda sensor again. Can any body explain why this is happening? The only thing I can think of doing is getting a new replacement and putting the cat back on and see what happens then. Any suggestions would be greatly appreciated.

Bosch 0258 003 229. on caterham site as MHK10006. but both numbers are on the part

Well guys new lambda fitted and so far everything is perfect, so I'll see how long it lasts with de cat on. Same part from Caterham £135.56 I bought mine online from RTG Automotive £43.03 free delivery so at that price I can afford to buy 3 for the price of 1at Caterham.

Chris would yours be the same part No that fits mine?

Thanks for the info Chris

Bingo I unplugged the lambda and no change to the running or idle. Temperature got to normal and still ok. I connected the lambda back gave it a few revs and engine started to hunt. So disconnected again and all seems fine. Went for a run including stopping and starting and to be honest it's the best it's been. Thanks for all your advise Chris but after giving some thought I've had the car for 3 yrs but only started to have this problem since last yr and nothing has changed to the car other than the de cat which I installed in the 1st year. If the lambda is the problem why did it pass the MOT last month? Also I can say that the fan kicks in at around 90C and normal running temp is just over 80C. The fan always seems to switch on when sitting in traffic on a hot day but not normal running temp. The question is now 1. should I replace the lambda and ditch the de cat and put cat back on.2. Is it ok to drive with the lambda disconnected. 3. What does the lambda do apart from control emissions. Thanks also to SM25T and can say this is a great club to be part of with all this knowledge at the touch of a button.

Thanks guys I will try tomorrow

Thanks Chris for your comments, my 7 is 2015 and the fan kicks in roughly after 80C. I do run the car with de cat and put the cat on for MOT. I now wonder if the lambda sensor has been damaged due to cat change a few times. If the lambda does kick in after 30 secs perhaps that is why I can drive off the forecourt when 1st starting and then plays up when I stop after a short period. Do you think it's worth changing the lambda or get live info test?

No trouble with starting 1st thing or idling right up to full temperature. If I say stop to refuel it starts ok and idles, but drive off the forecourt and stop and engine will not idle. I hold foot steady on throttle and engine hunts between 1.5k and 2.5 but not steady, take foot off throttle and engine stalls. Drive for a further .5 mile and all is ok. It appears this happens when the temp guage is between 40 and 80 once past 80 all seems ok. The last service I had no fault was found and suggested that he needs to get the necessary software to get a diognostic check. The only thing I can think is happening when temp guage reaching 80 is the thermostat probably opens but this should not cause the problem that I'm experiencing. Any help out there would be greatly appreciated.

I was going the other way in an orange 7 you turned into East Lodge Lane towards the Ridgeway about 4pm