Strange issue when revving under load.

[c.h 90]

Hey guys,

To me this is a funny one.
Recently my Clio 200 has developed an issue. When revving out to the red line it will suddenly hit a wall at about 6500ish rpm. The rpm needle will shoot down towards zero and backup. It’s happened a few times now. If I change gear and apply throttle again it sounds off, kind of like a misfire.
Yesterday I decide to keep the throttle open after it occurs, again it felt like it hit a wall, the car almost sounds like it’s on a very slow rev limiter and the rpm needle floats around the gauge bouncing from 4-5rpm.

Naturally I brought it to my mechanic but it was showing no codes what so ever.
Within the last 5000 miles it’s been fully serviced with all new oem coil packs as well. I’ve also replaced the MAP sensor (oem as well).

The car is due a belt change in about 2000miles so naturally dephaser will be changed then.

Me and my mechanic are at a bit of a loss.
Maybe it’s a crank or knock sensor but surely it would through a code?

The car has a ktr induction kit, akrapovic evo exhaust and a sprint booster v1 which was on it from purchase.


Sent from my iPhone using Tapatalk

 

[PAUL JA]

worth removing the sprint booster to eliminate that as the cause ?

 

[c.h 90]

worth removing the sprint booster to eliminate that as the cause ?

I was thinking the same thing. I’ve tried using it and seeing if the problem goes away but it seems to be there regardless of the setting I’m on.
I searched for faults but I didn’t see anyone complaining of faults.


Sent from my iPhone using Tapatalk

 

[burrellbloke]

Have you disconnected the Sprint Booster? I have not had one but I think that the Sprint Booster plugs in to the throttle system just after the pedal. It could be sending the wrong signals to the throttle?

 

[c.h 90]

So i decided to disconnect the sprint booster today. While taking it out I discovered it wasn’t in particularly good condition. The body was cracked and missing pieces.

The circuit board seemed to have a bit of corrosion as well. I was optimistic that this was the problem.
However once I took it for a spin the problem was still present.
I’m unfortunately back to square one.


Sent from my iPhone using Tapatalk

 

[Sean197]

What's your coolant temp needle sitting at?

 

[c.h 90]

What's your coolant temp needle sitting at?

I haven’t noticed any change, it comes up to temp and then does that classic clio thing of moving slightly below middle on the gauge and then back up. Temp sensor and thermostat where done maybe 4 years ago.


Sent from my iPhone using Tapatalk

 

[RSRowe]

Does sound crank sensor related to me. Faulty lambda sensors can also cause unusual issues without any fault codes showing

 

[c.h 90]

Is there a way of testing the crank or lambda? Or do I just take the hit and buy both?


Sent from my iPhone using Tapatalk

 

[c.h 90]

Just to close this out incase anyone is wondering. The car was due a timing belt etc. once that was done the problem disappeared.
My mechanics prognosis is that the dephaser must have gone bad causing a misfire/timing issue at the top end.


Sent from my iPhone using Tapatalk