power loss

[buellbolt]

hi,
sods law!!
i used to boast about the number of reliable renaults i have had and my megane cc is no different...until now!!
Warranty out on my 2004 cc 1.9dci by a month or so and now the problems begin.

Over the last week i have noticed a very brief loss of power at low-medium revs when accelerating, the engines dies for a split second and then lunges forward.

This has happened about 6 times over the last week and i am getting worried, any suggestions.

I have done around 30k, serviced as schedule and since reading this forum, did an oil and filter change about 750 miles ago (any significance here?)
My driving style is enthusiastic to say the least and the dci has been faultless until now
With no warranty and no funds available for repair, i am thinking about trading in for something else, i am being premature here?

i get no dash lights, no smoke, no whining, normal performance and poor mpg although tend to accelerate and drive quickly

[IainMW]

Hhmmm

This could be an EGR problem. My 52 plate Laguna 1.9dCi used to hiccup at about 1800rpm when setting off from standstill and sometimes when accelerating. The EGR was cleaned several times and replaced once (when it finally fell apart!!!)

Sadly the problem used to return after a few thousand miles, but there were so many other things wrong with it it was untrue

It could be a number of other things but you will need to get it invetigated. Cleaning the EGR would be benificial anyway and may improve your MPG?

Hopefully somebody else might have other possible solutions

[REDDERS]

This happened to my 120dci 2 weeks ago,your problem is a faulty air mass meter,it's located just to the left of the air filter housing.It has an electrical connection to it & you can see the top fixing screw of the two at the top of the sensor.This is a common fault on many diesels,it also happened on my last motor (golf 130 tdi).

cannot advise you on costs as mine was changed under warranty,but the golf one was about £70 & 1 hour to fit.

regards, martin..

[garrydane]

I've noticed a similar problem on my 1.9dci 130.

like buelbolt, you could say my driving is enthuastic!! I've noticed a few times when i have been driving a little more than enthuastically, that once i'm driving normally again, accelerating normally up through the gears, there is a momentary loss of power as i let the clutch out in each gear. this is only for a split second but is noticeably and quite annoying.

don't know much about the engine but thought it could have been dirt getting into fuel line from driving hard or something wrong with air filter as Redders says.

i mentioned it when i left it in for service but was told that if no lights were on on the dash, the computer wouldn't locate a problem.

as for mpg, i was putting that down to my driving style, as i frequently return under 40mpg. i'm currently testing the car to see what the max i can get from it is by driving like a OAP and not letting car go over 2,000 revs, and i'm still only managing 47.8mpg average at the minute!

[buellbolt]

well it eventually happened.
i had talked about getting it booked into renault this week
went to visit a mate tonight and when he got in the car, i stalled trying to pull away.
i couldnt get it started again unless i gave it some serious throttle.
it sounded like it was not running on 4 cylinders
still no lights on dash!!!
couldnt drive it so left it at mates.
went back 30 mins later and tried again, still no joy!!
had a poke about under the bonnet, dont know if coincidence but i got it started and managed to get it home although it kept trying to cut out.
feels to me like a fuelling or firing problem but i am stuck.

[IainMW]

Get it to a Renault Dealer or Diesel specialist ASAP. Don't drive it. You could do more damage to it and then end up with a huge bill!

If it is a stuck EGR then driving it will cook your Turbo!
If it's the Mass Air Flow sensor as Redders said, then be prepared for a big bill, they are not cheap.

[buellbolt]

took it to local renault dealer this morning, been diagnosed as faulty TDC sensor, not as bad as first feared, £150 all in to replace
will let you know if it is cured, getting it back tomorrow

[IainMW]

First time I've heard of a TDC sensor go on a 1.9dCi. It's usually 1.6 and 2.0 petrols that suffer with this problem

Anyway, Ho hum!

[buellbolt]

got car back after being in garage for 1.5 days.
replaced tdc sensor and connector
everything seems ok now

[candy_xyz]

THIS HAPPENED TO MINE ABOUT A YEAR AGO, AT THAT TIME WHEN I CAME ONLINE THERE WERE A FEW PEOPLE WITH THE SAME PROBLEM, IT WAS CALLED SOMETHING LIKE THE DEPHASER PULLEY....I FOUND FULL INSTRUCTIONS OF ALL THE PARTS AND HOW IT NEEDED TO BE CHANGED, BROUGHT THESE INTO RENAULT AND IT WAS FIXED (UNDER WARRENTY)!!!

unfortunately as i said it has come back now, it would have cost£560 if i had to pay for it myself, does anyone still have access to these instructions and diagrams??

It was a Renault Mechanic who posted the thread at the time!!! We all loved him!!