Register a free account today to become a member!
Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

  • When you purchase through links on our site, we may earn an affiliate commission. Read more here.

Before i spend a small fortune, can anybody help..? 172 Cup

  172 Cup

So i bought a 172 cup around a month ago from an ex-cliosport member; 50k, full service history, has been running great. I live in the French Alps, and unfortunately garages here are expensive, parts are more so (80 quid for a set of plugs), and my French is not perfect - i'd therefore like to diagnose the problem myself and get a local English speaking mechanic to do the fix.

A couple of weeks ago, i noticed a drop in power (throughout the range), and what i think is increased fuel consumption (although i do drive daily on steep mountain roads, so perhaps this is normal..)

In all, the symptoms are:

-Occasionally struggles to start - not every time and is at random
-When cold, the engine searches for idle - not hugely, but varies between 1000-1800rpm
-When driving whilst the engine is cold, the car will no accelerate smoothly - that is under constant, even acceleration, the revs will dip occasionally - losing/gaining power slightly
-I noticed unburnt fuel spitting from the exhaust
-The car has been 'gargling' increasingly - lift the foot off when accelerating, or very lightly touch the throttle and it gargles (sounds cool yeh, but guessing it isn't normal) - unburnt fuel again?
-Biggest problem: Car seems to have lost considerable power, evenly throughout the range - i just don't seem to have the acceleration i did when i purchased the car (possibly getting used to it, but this is more than that)

On board diagnostics say nothing. I've done a bit of reading on here, and from that believe it could be one/more of:

-Lambda sensors
-Coil pack
-plugs (already on the way in the post)
-leads (already tested - they are ok)

Without spending a load of money at the Renault garage, could anyone think of what else might be causing the problems?

Where should i start? Or should i just go to the garage and get it hooked up to a clip? The problem is i use the car for a 140km daily roundtrip.. so don't want to make things worse by waiting too long.



  RS2'ed 172 Cup
Sounds very much like when my Lambda went on mine.

Should be able to try yourself, swap the front and rear sensors round and see if things change, 22mm spanner IIRC.
  172 Cup

Thanks for the replies - i also forgot to mention that the exhust is blowing badly, and i have a new one arriving tomorrow. This probably doesn't help the problem.

When i'm getting the new one fitted/and spark plugs, i'll ask for the sensors to be swapped over to see if this helps matters.

If this is the problem, would you expect an instant improvement? Also, if it is the lambda, will i be damaging anything in the meantime by continuing to drive it?

  Megane dci 130
You'd never know with guessing I'm afraid. But if I was a betting man, my money would be on the coolant temperature sensor giving false readings.


ClioSport Club Member
  MX5 ND2/Twingo RS
Coolant temp sensor and MAP sensor are things I tried with similar issues and are cheap and relatively easy to replace/try.


ClioSport Club Member
^ not necessarily. Problems wont always show up on clip. Where abouts in the alps do you live? I just spent 6 months in val d'isere/la plagne.


ClioSport Trader
  Clio16v/Zoe Z.E.50
Code reading it on CLIP or other equipment won't show much at all but looking at the live data and going from there will.

Like ChipMk1 said in another thread, generally "mechanics" are good at fitting parts but rarely do they know how the internals and sensors actually work.

With that in mind take it somewhere that knows what they're doing rather than the cheapest place you can find.

(does sound CTS/H02 related)
  172 Cup
Thanks Mick,

Its just a trouble finding a specialist around here - the only option i think is the main dealers.

Patrick - i live in Morzine - Val d'isere's a great place!