Clio 182 Poor MPG

[Benjiman46]

Hi all! I'm at my whits end now so hope you can help.

My Clio's MPG has taken a sudden downward drop, I used to get around 42mpg easily on the motorway but now I'm struggling to get 29-30mpg.

The only thing I've changed is to fix a blowing exhaust with a bit of silicon RTV, Where I unplugged the Lamda sensor (electronically) so I could get to that flexi joint gasket that always blows.

Another notable thing I can think of is the immobiliser had a brain fart and wouldn't recognise the key for about an hour; the car would turn over for about 5 seconds but not catch, then the starter would stop spinning. It took me an hour to get it going and I had the battery off and everything (to see if it would reset anything) trying to get it going.

The last thing is that something doesn't quite feel right with the front end, like the steering is a bit numb, it could be a wishbone bush from experience... Would this put the tracking out enough to mess with the MPG? It all started after I fixed the exhaust, even the weird steering feel.

I'm pulling my hair out -_-

Any help will be appreciated

Ben

 

[Benjiman46]

Forgot to mention spec -_-

It's Decatted, RS Tuner pops and bangs map, Stainless exhaust and ASH custom air fliter. All of which I've had for ages and had no previous problems with MPG.

 

[bloke]

stupid map won't help to say the least, check o2 sensor, then brakes and go from there.

 

[bozothenutter]

Does it run crap when cold?
If yes then probably the lambda.
You could test by swithing them around...will throw up an eml light ofcourse

 

[Benjiman46]

No runs fine cold :/ revs a little high but that's about it

 

[Benjiman46]

And by revs, I mean revs at about 2000 rpm on tickover

 

[ADS_V6]

that tickover aint right m8

 

[Benjiman46]

Even with the remap? It settles down to normal after about 15 seconds... Could that be down to the Lamda sensor then?

 

[Addicted]

Yeah 2k revs isn't right at all.

 

[Mr Plums]

That seems very high.

 

[Diagro]

What's the idle when warm?

 

[GavC]

Tried resetting your MPG?

 

[bloke]

thought the 2k tickover was a wind up!!

 

[Benjiman46]

Tickover is high because of the remap, it has raised the warm tick over a tiny bit (to around 1000 rmp) but when it's stone cold it is around 1800 rpm to improve the warmup behavior but when changing gears it will peak at 2000 rpm... What are we all thinking then? Try swapping the Lamda sensors around to see if that improves it?

I'm going to plug it in later and see if I can get any codes, I haven't got the EML on at the minute but it has been on and off every now and again since I bought the car (Just put it down to sh*t fuel)

I'll post my results!

Yes GavC... Yes I have

 

[Benjiman46]

Fault codes came up as:
DF0006, DF0088, DF0330, DF0121 - Knock sensor 1 Circuit - Memory (meaning intermittent fault)
DF0092, DF0967 - O2 Sensor Front - Memory (again meaning intermittent fault)

I know what the obvious answer will be... Change them both... But I'm trying to understand why the O2 sensor or the Knock sensor, or a combo of both are throwing my MPG out

Cheers in advance!

 

[Benjiman46]

 

[bloke]

Tickover is high because of the remap...

...What are we all thinking then?

worlds worst map??

 

[Benjiman46]

What is it with you and the remap? People use RS Tuner remaps all the time pal, it isn't the map. The remap raises the engine revs slightly more than standard when it's cold, so it doesn't sound like a bag of sh*t, coughing and spluttering when it's cold. I've put the standard one back on to eliminate it too and guess what... MPG is still down, it's still revving too high and I'm getting the same fault codes. If you've got nothing constructive to add to the conversation other than "Your remap is rubbish" go on a corsa forum or something.
None meant.

 

[Battery Nonce]

I'm very confused, or probably reading it wrong but your lambda sensor is knackered and you're wondering why your mpg is bad?

The lambda sensor identifies the air/fuel ratio in the exhaust gases and adjusts your injector output according to if it's running too lean or rich.

My guess is that the pops and bangs map has chucked too much unburnt fuel in the exhaust system and your lambda sensor is caked in unburnt carbon crap and it's giving a delayed/no signal to the ECU which is throwing off your MPG.

 

[Diagro]

As Above. Replace the lambda asap

You say you have put the normal map back on and its still revving too high? Not the map then something else is wrong.

I also have an RSTuner Map and it only revs at 1.5k when cold and 950 when warm

 

[chaski]

I also have an RSTuner Map and it only revs at 1.5k when cold and 950 when warm

Is yours regular 98ron map though? Because the OP is running the pops & bangs 98ron map.

 

[Diagro]

Probably that map that's caused gimme issues then.
Mines the 97+ Ron map