Lambda sensor and gear ratios

Hello there!

I just picked up a used Renaultsport Clio 200 (with the Cup chassis). 10 years old, 52,000 miles, very tidy. I would appreciate any help from this community please and a pleasure to find this online!

Within two weeks of ownership, the car started spluttering. I was able to coax it home, park it and then book it in for a fix. As soon as the engine reached its warm idle, it would hiccup and I had to turn it off. The 'check emissions' light came on.

Turns out the lambda sensor was awry, which meant fuel was not being sent to the engine in correct quantities, causing the coughing. A new one was duly ordered and fitted by a local Renault specialist.

Upon collection just now, on the drive home, I noticed that when I change from fourth gear to fifth gear, the engine reves actually increased. In fact, in fifth, it revs nearly as high as third, and sixth nearly as high as fourth. At 50 mph it was revving up past 3,500 rpm. But because I'd only had the car for a brief amount of time before it broke, I'd only done one motorway journey (it went to the technician on the back of a lorry) and I couldn't recall if this was the case originally.

So my question is, has anyone experienced this before, or is this how it's meant to drive and I'm being a bit daft?
 
Could it be that the gear linkage has come away from the housing?

I had a similar issue whereby the linkage had come away from the box and the gear locations had changed so that 3rd gear was where 1st was, 3rd changed to 5th and so forth.

The linkage is below the battery tray box but I’ve got a feeling you may be able to access it without removing the tray, which someone else can hopefully confirm.
 
Aha, thank you for the reply! I didn't think of something like that, because come to think of it fifth feels like third!
 
It’s unlikely it was knocked out during the lambda replacement, although not impossible. I’d like to say it’s most likely just a conincidence.

On my Clio, I noticed the change immediately. However that was after some “enthusiastic” gear changes shall we say!