2003 Clio P0170

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nenenaiad
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Joined: Sat Feb 23, 2013 7:48 pm

Re: 2003 Clio P0170

Post by nenenaiad »

Hi Matt,

I learned a lot this afternoon.

I attempted a WOT but realised that this is not as wanted since I went from 2K revs to WOT and DID not drop back to idle before doing a WOT. I wll repeat the test in the morning and do it correctly this time.

I have attached the file called alpha in pico format for you to be critical over. My comments are as follows :-

- I need to start earlier in the frame to catch ALL of the WOT
- I need to reduce the noise on the waveform

What would you like me to change ?
alpha.psdata
2K to WOT NOT idle to WOT
(6.91 MiB) Downloaded 580 times
Regards

Dave

nenenaiad
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Re: 2003 Clio P0170

Post by nenenaiad »

Hi,

I have looked at the graph myself.

I noted the variation in tickover speed as I was sat in the car. This tied up with the MAP output. Presumably something is causing this and the fact that the Lambda sensor is responding to this rich / lean condition condition must mean that extra fuel is being put in.

I cleaned up the signals in the file by changing the bit rate.

Regards


Dave

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Fat Freddy
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Re: 2003 Clio P0170

Post by Fat Freddy »

Hi

Just a couple of tips:
I need to start earlier in the frame to catch ALL of the WOT

You really need to increase the time per division (Top left of the screen). At the moment you have it at 500mS (a total of 5seconds across the screen), which is a bit short for this type of capture. Try increasing it until you are sucessfull to capture what you want.
If you want to get fancy, try setting up a trigger (Bottom left).
I need to reduce the noise on the waveform
I cleaned up the signals in the file by changing the bit rate
Personally I don't like to use the "bit rate" to tidy up noise. You are better off ticking the 'activate filtering' in the 'Low pass filtering' (available in the same drop down menu as the 'bit rate'). then adjust the amount of filtering up or down.
But......The lower the number the heavier the filter.
Far more flexability than 'bit rate'.


HTH
FF

nenenaiad
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Posts: 17
Joined: Sat Feb 23, 2013 7:48 pm

Re: 2003 Clio P0170

Post by nenenaiad »

Hi,

Many thanks for that.

Am learning all the time, and intend to put the corrective measures in place tomorrow morning when I do the run I should have done the first time around. It is all giving food for thought which is what it is all about.

Thanks for your comments, all noted.

Regards


Dave

nenenaiad
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Posts: 17
Joined: Sat Feb 23, 2013 7:48 pm

Re: 2003 Clio P0170

Post by nenenaiad »

Hi All,

I have followed up the earlier WOT test I carried out, and implemented the recommendations some of you made, and attached the second Beta WOT Test below.

I would confirm the following regarding the vehicle involved :-

2003 Renault Clio 1.2 16V - Engine D4F

Problem - P0170 logged code with Malfunction Indicator Lamp On ---- After reset, code reappears after say 50 miles.

Test performed with engine at normal running temperature



In terms of the WOT test performed, the engine and therefore the content of the Pico buffers represent the following sequence:-

---- Running at 2K

----Running at idle

----Taken to wide open throttle, followed by........

----Running at idle

I have experienced some difficulty for whatever reason in uploading the beta file. Pico have split the file up into the buffer sequence and the individual files are below.

WOT Test file beta.------------------- split into 7 waveform files
beta5.psdata
(1.46 MiB) Downloaded 454 times
beta7.psdata
(665.66 KiB) Downloaded 487 times
beta1.psdata
(1.61 MiB) Downloaded 508 times
beta2.psdata
(1.53 MiB) Downloaded 524 times
beta3.psdata
(1.5 MiB) Downloaded 484 times
beta4.psdata
(1.68 MiB) Downloaded 503 times
beta6.psdata
(1.53 MiB) Downloaded 431 times
Regards


Dave

mteste03
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Joined: Mon Oct 29, 2012 9:14 pm

Re: 2003 Clio P0170

Post by mteste03 »

Hi,

Try increasing the time base further so you have maybe 20 - 30 seconds across the screen. There are no hard and fast rules so just change it until you get the fast idle, full throttle and return to idle on one screen capture. It's all good learning :P .

I need to have a better look at what you uploaded so will do that when I have chance later.

btw - What do you think it's telling you? What do you expect to see from Lambda during each section?

Matt
Attachments
03 corsa 1.2 maf and lambda.psdata
(79.85 KiB) Downloaded 455 times

mteste03
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Joined: Mon Oct 29, 2012 9:14 pm

Re: 2003 Clio P0170

Post by mteste03 »

try and get something similar to the file I uploaded.

Matt

nenenaiad
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Joined: Sat Feb 23, 2013 7:48 pm

Re: 2003 Clio P0170

Post by nenenaiad »

Hi Matt,

Thank you for your reply.

I will do another WOT tomorrow morning and modify the time base. I shall include with it any comments I can make about the sections and what they show.

Regards


Dave

nenenaiad
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Joined: Sat Feb 23, 2013 7:48 pm

Re: 2003 Clio P0170

Post by nenenaiad »

Hi,

Latest WOT test called gamma is below.

This scan starts at 2K, goes to idle, then WOT, then back to idle.

Setting the Resolution Enhancement to 16 bits cleans up both plots well.

I shall edit this later today with some observations about this and the previous plot.
gamma.psdata
WOT Test
(360.49 KiB) Downloaded 540 times
Daves Comments.

In the very early days of being on this forum, some of the early suggestions suggested carrying out a fuel pressure test.
I felt that since this parameter under pinned all the orders it would be a really good idea to check it.
Most of the relatively inexpensive pressure test kits I could get hold of seemed to only cater for schrader type connections and so far I have been unable to get an adaptor to convert from Renault to schrader - so if you suggested this I think your right.

And so to the plots. Starting with Beta..........

I noted that at WOT the voltage from the MAP was 4v and I think that 5v was expected.

During the 2K run I noted that the DC Average from the lambda sensor was 602.9mV which indicates a rich bias.

And in both Beta and Gamma WOT plots, the lambda shows a rich spike at half the MAP plot widths and then stays lean which I understand it should do.

I await any help.

Regards

Dave

mteste03
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Joined: Mon Oct 29, 2012 9:14 pm

Re: 2003 Clio P0170

Post by mteste03 »

Hi,

What voltage are you getting from MAP with key on engine off? Would expect 4.8ish volts, even 0.3V out of spec has potential to cause big fueling errors. I don't have a known good for this engine, maybe someone else does.

Why would you expect a lean mixture under full throttle?

Matt

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