Yet another lumpy idle…

[Brian J]

So my recently acquired 182 runs lumpy at idle and low revs.

The PO bought it as a project and then it sat in his shed for a few years. Apparently when he bought it, it ran ok apart from the dephaser being shot. This year he stuck an exhaust on it and got the belts, dephaser and tensioners replaced at a mate’s garage, then found the brakes were shot and it had a rusty sill, and punted it on to me. (Sucker)

When I got it, I fired the parts Cannon at it. I figured it had 120k so I figured a refresh was due so I fitted:
New injectors (Magnetti Marelli)
New plugs (correct Ngk)
Leads (beru),
and coil (canbriaire)

The running has not appreciably changed at all. The old plugs looked new but very sooty.

There are no warning lights or error codes but when idling, values are as follows:

manifold pressure is around 620mb at idle, and just over 1000mb with the engine off.
Upstream lambda oscillates between 19 and 890mv or so.
downstream lambda is pegged just over 400mv.

I’m figuring I have wasted my money on plugs, injectors, leads and coil and should have had the valve timing checked as the first stop… what do you think?

Also, what are my chances it will still pass an mot emissions check as-is?

 

[npt]

My cup is very lumpy on idle when cold, or when driven the first few miles, timing is bang on and it runs perfectly otherwise, its always been this way since I've had it..I've just thought that's the way it is, although rather annoying..

 

[Mr Underhill]

How lumpy? Got a video?

I've had 3 Clio Sport 182's - still have 2 of them - and they're all like sowing machines from cold and at idle. Here's a video of one of them.

Stock map, correctly timed by a reputable garage, genuine parts. Just how they were meant to sound from the factory.

I had the track car Group N timed and then mapped at EFi, the sowing machine went and in return, I got a lumpy sounding engine which periodically cut out when cold.

It transformed the way it drove though. So i suspect timing, and mapping is your issue here.

 

[RustyMojo]

I don’t think you have wasted your money, as to be perfectly honest. Most of those parts would likely have needed to be changed in the next year anyway! These cars love killing injectors. As with Lambda sensors! I’d be suspicious of it being timed correctly as that seems to be a regular c**k up of non specialist belt replacement. I would also ask if you fitted an aftermarket coil pack? Anything other than the Valeo ones, in my experience are very hot and miss!

I would, if it were me. Get someone reputable to check the timing. Also where are you located, maybe there is someone local who can lend you a working coil pack to see if that makes a difference.

 

[Mr Underhill]

These cars love killing injectors. As with Lambda sensors!

Strange you say that Russ as I've never had an issue with any of my 3 with those components. I'm on 40,000 miles with the BG on the same injectors and never replaced a Lambda sensor.

Before I mapped the track car at EFI, I asked Chris if I should change the injectors before the map and in his own words "most originals are still working ok, they're just starting to become unreliable at 16+ yrs old".

And I think therein lies the problem with a lot of these cars. Age, a shortage of genuine parts (although I understand Magneti Marelli are the same as factory) and previous owners' reluctance to put money and time into them. Pass the problem onto somebody else so to speak.

 

[RustyMojo]

I don’t doubt it’s their age Jon, but it’s a regular failing nowadays. We see it all the time on just this forum. I had one fail on my car. So I replaced all 4. It just made sense to given the relatively low cost. Lambda, people replace with non genuine items. They just don’t last. Certainly in my experience. Never had a problem once a proper Bosch unit was fitted. But they don’t last forever and there are many examples on this forum alone of folk with poor running resulting from lambda and injector failure.

 

[Mr Underhill]

I don’t doubt it’s their age Jon, but it’s a regular failing nowadays. We see it all the time on just this forum. I had one fail on my car. So I replaced all 4. It just made sense to given the relatively low cost. Lambda, people replace with non genuine items. They just don’t last. Certainly in my experience. Never had a problem once a proper Bosch unit was fitted. But they don’t last forever and there are many examples on this forum alone of folk with poor running resulting from lambda and injector failure.

Oh I've no doubt the issues are there, like you, I read about them every day. As I said above a lack of genuine parts doesn't help.

But you only get half a story most of the time at best. If I'd had read these forums prior to buying mine, I probably wouldn't have 😂 Apparently they all leak oil, are lumpy at idle, yada yada. Those Renault salesmen must have been special, that's all can say.

 

[Brian J]

Wow!
thanks all for your input. If it helps, this is what it idles like cold:

Hot idle is worse, it will pretty much dies any time you dip the clutch if the revs fall.

the coil is not Valeo, it’s Cambiare, but it’s certainly no worse than the old one.
I have given in and booked it in with Chris @ Beaniesport next week to check the timing. Given the nature of the belt change, I’m pretty sure that will be the issue.

 

[Mr Underhill]

Doesn’t sound that bad tbh. I was expecting and have heard a lot worse. Timing and a good map will sort.

 

[Sunday_Driver]

Sorry to revive an old thread! But @Brian J did you end up finding a solution? Was the timing in fact out a smidge?

My 172 is running the exact same as yours in that clip and it’s starting to do my head in!

 

[Brian J]

Hi, yes. My timing was indeed out by around 7 degrees. I got it rest at a specialist, and it is like a different car. Both in terms of idle and drivability. I have an after clip on my tidy up thread in the projects section If that helps.

Although doing a timing belt on these is a pain, access to CHECK the timing is actually not too bad. Some of the inlet needs to be removed, and a new pair of cam end caps will be needed. I think it took less than £10 in parts and about 1/2hr in labour for the specialist to check mine And tell me it needed done.

I hope you get sorted

 

[Sunday_Driver]

Appreciate it man, thanks for the reply!

 

[jameswrx]

I bought a 200 with a recently done belt, the lad had also fitted induction kit and full decat system and not mapped it.

Obviously ran like a bag of crap (as the mk3’s do).

I booked it for mapping as soon as I got it, fitted the secondary cat..

When I took it for mapping he said the vacuum at idle and choppy idle suggested AM cams but they were std so assumed timing was slightly out. We carried on with the map (my choice) and it made 201bhp. It’s noticeably quicker everywhere over my 197 and especially low down response for a 200 is really sharp.

Accidental result. I’m going to redo it soon but be funny if it’s not as good with perfect timing.