Clio V6 Mk2 enigne says *poff*

[pternstrom]

Hello all,

First I must say that I really like my clio v6. It has proven itself both on the road and several tracks in sweden and in europe. Its a great car, that I use almost every day. It has 22000 km on the clock.

just a week ago i noticed a weird sound coming from the left air intake behind the door. If you, when the car is idling, suddenly and rapidly press the gas, the engine says *poff* from the intake before revving upp. The sound resembles of a mechanical sound, but it originates from the intake.

If you hold your hand infront of the air intake you can actually feel some air being pushed to your hand simultaneus to the *poff* sound.

There is a microsecond delay after the sound before the engine revs up.

idle - press gas - *poff* - rev up

If you try it from higher revs, the sound goes away. Delay is gone, too.

I have also noticed a slight decrease of power throughout the powerband, but I am not completely sure.

Its now sitting at a stockholm renault shop. Although the staff is very professional, they cant find anything wrong with the car. This is due to my car being the first V6 they have done work on, since my V6 is the only mk2 in Scandinavia. They found a dirty air filter (new air filter costs 160£!!), but the car makes the poff sound even with the filter off.

So, my question to all you V6 people out there, have you ever heard anything like this? What could be the problem? Any ideas, anyone?

Peter

 

[BenR]

sounds like a spit back, most of the time caused by ignition timing which is too retarded, which would also explain the reduced power your experiencing.

Check your coilpacks.

 

[Dash]

Not too sure how to answer this, but I though all V6s made this sort of sucking poff sound when you blip the pedal?

 

[MATT BLACK]

As ben r said - it sounds like the coil packs to me

http://i2.photobucket.com/albums/y37/j3ned/00095733_1.png

 

[rmccardal]

£36.64 ... what a deal.

 

[mitch_]

James is right, all V6s Mk1s and 2s do it, depends if yours is now doing it worse than it did before. I always put it down to an induction problem....

 

[pternstrom]

Thanks for all replies.

The renault guys says its definetly not the coil packs, since the coil packs have an "on / off" behavior. If they fail, I will certainly notice it by serius loss of power.

But still, can a damaged / worn coil pack cause this problem?

 

[tidyclio]

have these got electronic throttle?ive heard a lot of cars eith these making the noise you say but thats normal on them

 

[MATT BLACK]

You need to get the car hooked up to a "clip" Renault diagnostic computer and do a full systems check. It will record any faults that have occured or if its an intimitant fault take the car out on a test run with the clip attached and it will then show any faults. The fault can be deleted and hopefully will not re-occur, but if there is a problem the clip should find the responsible part and then you can simply change it.

I had a similar problem and it turned out to be a cracked piston ring - but then again i was using a 100 BHP nos kit, lol

 

[MATT BLACK]

Keep an eye out for this symbol flashing - if it does it means there is an electrical fault on the car - usually the individual pencil coils

http://i2.photobucket.com/albums/y37/j3ned/warninglight.jpg

 

[pternstrom]

The renault people have hooked it up to their diagnostic computer and it reports no errors. The dashboard warning light is not flashing either.

A light that flashes all the time is a green gearbox-lever at the right of the console.

 

[BenR]

youll have to explain the symptom a bit clearer.

FBW throttles always give crap throttle response.

BUt are you getting a spitback (burning mixture in the plenham) usually caused by ignition timing or too lean a mixture so the mixture is still burning when the inlet valve opens again.

Or is it literally just a noise as the engine tries to inhale?

 

[hog1]

What do you mean by flashing green gearbox light at the rt side of the console? This is the cruise control, speed limiter engagement light or it is on UK market.

 

[mitch_]

I think he means the up-shift light.... In other words hes enjoying the rev-limiter!!

[Edited by mitch_ on 8/22/2005 10:55:45 AM]

 

[pternstrom]

Thanks for all good input in this matter. After clearing out the filter from dirt (no way Im paying 160£ for a new filter) the car runs better. The *poff*-sound is there to stay though. It might be something with the upgraded engine management system the renault dealer installed at the last service. The *poff* sound sounds weird, but if you guys say its normal then I guess its OK.

Thanks again!

Peter