Acceleration / Cruise Control Issue?

[smudger92]

Hi Everyone,
I'm hoping someone may be able to point me in the right direction with an issue that started yesterday and is progressively getting worse.
My apologies in advance if it appears I am rambling, or not giving the right info.
Anyway, Here goes..... I own a 2004 CLK270 which I love. I have had it for nearly a year now and the only issues i have suffered are a couple of headlamp bulbs.
My problem started yesterday when i was driving across the M62 from Manchester to Huddersfield. I engaged cruise control (CC) and sat back as i always do to let the car do the work.
The cruise control worked fine but it felt as though the car was accelerating and slowing down constantly. I have never had this experience before, so i disengaged CC and tried it without. Didn't appear to be any problems when disengaged. Put it back onto CC and same happened.
Same thing happened on the way back, i even tried different speeds to see if that was an indicator of the problem. But no difference.

Today, I had to drive from Manchester to Poole as that is where i am working at present and the same thing was happening again. However, i have felt and noticed other things now.
If i accelerate in 5th or 6th it feels as though there is a slight back pressure from the accelerator pedal and then she accelerates.
I am sure i was noticing a small puff of smoke from the exhaust as well. However, i may be paranoid, but am pretty sure there was something going on.
As i came off the motorway and onto a dual carriage way i changed down to third to overtake someone and all that happened was that the engine revved the B**^^*ks off itself, i changed back up to 4th and she accelerated. However not at a great pace.
I found that 3rd gear acceleration would work if i was changing up as normal but all acceleration just seemed and felt so slow.
I am expecting this to cost me an arm and a leg to sort out, (ever the pessimist), but am hoping it isn't. I am due a "B" Servicing in 700 miles as well. Not sure if that has any rellevance.
As i am working near to Poole and Bournemouth, any local recommended garages would be greta.
Am hoping that one of you guy's has come across this before and can help as I don't have clue.


Thanks for reading

Dave

 

[smudger92]

I have been reading through a lot of previous posts and was wondering if maybe the "CAT" was possible getting blocked.
Would certainly explain the feeling of back pressure on the accelerator pedal and then the sudden release.
I understand how easy it is to attach something to a snag and talk yourself into a solution, so am hoping someone can point me in the right direction.

Would hooking up to diagnostics help?
Any help is greatly appreciated

Thanks

Dave

 

[GordonTarling]

I don't think there's much that can give you feedback to the throttle pedal - it's 'drive by wire', so the pedal is only linked to a position transducer, which sends electrical signals to the ECU. Really, the only way to find out what's wrong is to get it hooked up to a STAR machine and have the codes read.

 

[renault12ts]

As above, get the codes read. Could be something as simple as a new Maf, which isn't too dear...or something worse.

 

[corned]

Olly at PCS is within striking distance - Horndean/Portsmouth?

 

[Shude]

As i came off the motorway and onto a dual carriage way i changed down to third to overtake someone and all that happened was that the engine revved the B**^^*ks off itself, i changed back up to 4th and she accelerated. However not at a great pace.

When this happened to me it was gearbox atf level. Minor leak was the culprit (underside of car was rust-free though! ).

 

[smudger92]

Thanks Guy's,
Am arranging STAR diagnostics over the next coupel of days. Hopefully it will give the answer.
Thanks for your quick replies.

Dave

 

[Dieselman]

possible split boost intake pipe causing lack of boost.

 

[smudger92]

Thanks for the advice guy's.
For once in my life, i hope it's something simple!

 

[smudger92]

Thanks to everyone for their help.
Got it put through a STAR machine, while i held my breath.
Found that the problem was due to a split Intercooler pipe.
PHEW!!
Drives like a new car again.

Many thanks once again, just need to sort out the B Service now.
Am back in NW next week, so will give Ian a ring at 124

:bannana:

 

[renault12ts]

DM wins...again.