Megane II 175 dCi Check Injection fault

[Sync0r]

Hello,

I am getting the "Check Injection" fault message. The only noticeable difference in the car is that at idle it feels slightly rougher than normal and when I turn the engine off it stutters to a stop. The acceleration/power still feels the same as always.

I took it to a Renault specialist and they thought it was the DPF, so they put some cleaner through the fuel system and reset the code and the fault appeared to go away. A week later the fault code reappeared and the rough idle. So I read around the forums and a few people mentioned that it could be the EGR valve. So I took that apart and cleaned it out, this made no difference.

I convinced myself that it was the DPF getting blocked again so I took the car to K-Tec Racing to get the DPF removed and the car remapped (To be honest I was just looking for an excuse to get this done). So it went onto the dyno and its putting out 210bhp and 354lb ft torque. The new map cleared the error codes and the car seemed to idle great until a week later the rough idle and stutter when stopping the engine is back along with the "Check Injection" warning.

Has anyone got any idea what this could be?

Don't want to keep on taking it to Renault garage for them to tell me its one thing when its incorrect as I'll just keep throwing money away in labour costs. My thoughts are that it might just be a faulty sensor as clearing the errors on the ECU seems to make the problem go away.

[Sync0r]

So I got my ODBII reader out and checked for fault codes..

p242a exhaust gas temperature sensor circuit bank 1 sensor 3

Not sure this is the correct meaning for the code as its a generic code, Renault may have some specific description for it.

So anyway, I decided to clear the codes and the fault has gone away, no lumpy idle or stuttering to a stop, just like before. But I expect in about a week it will come back...

Anyone have any ideas what this is?

[MilosB]

still sound as a DPF, as it has a sensor before and after the DPF.
I know you have removed it, but the sensors must still be there, and it is possible that a sensor or a lead going to it is damaged, and cosing an ocasional error.
ps, which megane 2 dci engine is 175bhp ?

[Sync0r]

2.0 m9r I believe.

So heres a close up of my new dpf delete pipe, courtesy of K-Tec.

https://www.facebook.com/media/set/?set=a.631609913528445.1073742037.187795637909877&type=1

So which one do you think it might be, looks like 2 sensors on DPF, I read that these are pressure sensors, to measure a before and after pressures to see if dpf needs a regen. And there looks to be 2 further up, is one of these a temp sensor? Or a lambda sensor?

Thanks

[AlexB]

It was, probably, the EGT sensor that caused the problem with the DPF in the first place...

This link can be also relevant
https://www.renaultforums.co.uk/showthre ... 882&page=3

[Sync0r]

Is the EGT sensor pictured in the link I posted?

Cheers

[Sync0r]

I also had a pending fault code

p2101 throttle actuator "A" control motor circuit range/performance

The EGT code was Stored.

I'm note sure what the difference is between Stored and pending?

[AlexB]

"Pending" means an intermittent fault that may clear itself after 40 start cycles, or become a mature diagnostic trouble code DTC.

[AlexB]

Looked at your pictures - no idea. I don't have this EGT sensor. Nice map, by the way. It makes the torque delivery much smoother. Just make sure to use a synthetic oil (most synthetics are actually refined mineral oils), which are known to be based on PAO and/or esters.

[Sync0r]

Ok thanks. Yeah I'm using Mobil 1 ESP Formula 5W-30. This is good enough right?

The torque is fantastic now, however I do sometimes get wheel spin in 3rd and 4th now, especially on painted white lines argh. New tires needed soon I think.

I'll try and have a hunt around the net to see which sensor the EGT is.

[AlexB]

Yep, it is a proper synthetic, probably PAO basestock. These don't have advanced lubricity, but excellent in winter, when condensation occurs. The MSDS document explicitly states that it does not polymerise (as mineral oils do). Its high temperature performance is about the same as with most 5w40 oils, which is impressive.

The tyres... Under +7C all summer tyres begin to struggle, especially the wide tyres and the fuel-saving tyres, which have no chance to warm up. At mytyres you can order the list by wet performance, have a look there and check camskill for prices.

[Sync0r]

Ah ok, that'll be why my tyres have been rubbish lately. I currently have Conti Sport Contact 5's but they wear out way too fast. Going to try Goodyear Eagle F1 Asymmetric 2's this time.

So I have worked out what all the connections are going into the DPF delete pipe, there is a pre and post temp sensor and pre and post pressure sensor for the DPF. So perhaps changing the temp sensors may fix the problem.

Question is how do I find the part number! Might have to take a wander to my local Renault garage, its just across the street from my work.

Cheers

[MilosB]

I would really just first check all the connections are OK in that area.

[freelanderuk]

i would check with who did your remap , as when i had mine done and the dpf removed ,i was told that anything to do with the dpf and the regen cycle was over written and taken off the ecu

[MilosB]

but the sensors must stay connected and in god condition (so i read on few dpf removal company web pages) so if the sensor is bad, or there is a bad connection that shortens out every few days than it could still couse an error? (just a though and more like a question to freelanderuk )