Data Logging

[mcstang]

As you may have read on other threads I'm having serious grief with my car bogging down.
It sounds shit,drives shit and is coming an unhealthy obsession.
Plugs,transmission fluid,fuel filter,oil filter,throttle body have all been changed lately.
I've finally figured out how to datalog, at least I can read it though I haven't a clue what it all means.
I also don't know to post stills on here of the data logging which I've seen others do.
Any chance you chaps could ask me readings on subjects which may cause the bogging which I can post back here?
I'm thinking fuel pressure,maf voltage,fuel trims and the likes.
Even transmission readings-she aint changing down when she should.
Would these be of some use for you chaps to figure out my issue?
I have no engine codes and never have.
Thanks in advance.

John

(I have a Diablo Predator U7140)

 

[BruceH]

If you have Windows 7 use the clip feature to capture and save a screenshot as a jpeg. To post it open a photobucket account and download the picture there. From photobucket post an img link and the picture will show up on your posts.

If you are using xp then the picture can still be saved with paint but the process is a little more involved. There are online instructions that will turn up in a search.

Have you checked all of your vacuum lines? How about the intake manifold itself for loose bolts?

What are your long term and short term fuel trims?

 

[mcstang]

Testing Testing

Cheers Bruce,
I think if you click on that you can see it.
That sums up my problem.
5th Gear (auto) and under 20mph.
She aint changing down.

More available

 

[mcstang]

Here's another
Ask away.
I data logged today for about 20 min but didn't really go flat out through the box as it was wet and, well, the car runs shit.

 

[BruceH]

I think those are the long term trims. Can you post up the short term and long term trims on the same shot and make sure the scale reflects trims?

 

[irishpwr46]

what do you have done to the car?

 

[mcstang]

I think those are the long term trims. Can you post up the short term and long term trims on the same shot and make sure the scale reflects trims?

Cheers Bruce,
Looking at the fuel options on the left of the graph do you know which item shows short term trims-none of them say it?
Cheers

 

[mcstang]

what do you have done to the car?

Just now she is only running SLP exhausts and a K&N panel filter.
Also 93OCT performance canned tune from Predator (not a custom tune).
She runs shit regardless of what tune is in her or what air intake is fitted( removed C&l)
I'll post later my 02 sensor readings as I reckon they're odd also.
Cheers

 

[Swarzkopf]

mcstang - does that Predator let you save your data log in .CSV format? If so, post it up here - it's better to analyze the data as it occurs.

Sounds kind of like your O2 sensor(s) are bad - they should switch rapidly at idle between low readings and high (say, 800 volts on the high end and below 100 or so on the low end). If they aren't switching fast, they're probably bad.

If they are reading low at WOT, we can maybe identify a fueling issue.

Besides that, we can look at your MAF HZ reading - it may need cleaned. I'd also scan for cylinder misfires and see if one cylinder is causing problems (ignition coil, plug, injector, etc).

 

[mcstang]

Cheers mate,
I'm at work just now but I'll check that .CSV thing when I get home.
I initially thought it was the 02 sensors but my upstream go up and down and the downstream are fairly constant.
When I say the upstreams go up and down it takes maybe 3-5 seconds for them to go up and down.
I think they should go through the motion in say a second?
So there working but not as efficiently as they should be?
When I first got the car, it had a C&L street cai fitted but the car wasn't tuned to accept it.
There were a couple of codes showing the car was running lean.
Although I finally got the car tuned (which got rid of the codes), could this running lean have screwed up the 02 sensors?
Watch this space for more graphs and stuff.
Cheers

 

[mcstang]

[/URL][/IMG]


Here's my 02 sensor thingie

 

[mcstang]

[/URL][/IMG]

Here's the MAF

Still trying to suss out that live thingie.
Let me know what else you need.

John

 

[BruceH]

Cheers Bruce,
Looking at the fuel options on the left of the graph do you know which item shows short term trims-none of them say it?
Cheers

I'm used to them being labeled as ltft and stft bank 1 and 2. All I want to see is if there is a lot of correction being applied with the trims. If so it can help to find the problem.

 

[mcstang]

I'm used to them being labeled as ltft and stft bank 1 and 2. All I want to see is if there is a lot of correction being applied with the trims. If so it can help to find the problem.

Hi Bruce,
I'm sure those options are shown on the device itself, they don't appear to be something i can show on the graph however.
I'll plug it in later and see what they are saying.
What's your thoughts on the 02 sensor graph?

 

[Swarzkopf]

Hmmm....O2 switching looks OK from what I can tell. Maybe it's worth swapping them for the hell of it. They're pretty cheap from what I remember.

O2 values at max look about to be what they should. I guess fuel delivery, when it's being commanded properly, is OK.

I'd probably try cleaning the MAF with some aerosol MAF cleaner, too.

 

[s8v4o]

Look here. I did a quick google search and maybe this will help you figure out what parameters to log.

http://www.svtperformance.com/forums/tuning-la-carte-375/813055-useful-diablo-predator-table.html

 

[mcstang]

Hmmm....O2 switching looks OK from what I can tell. Maybe it's worth swapping them for the hell of it. They're pretty cheap from what I remember.

O2 values at max look about to be what they should. I guess fuel delivery, when it's being commanded properly, is OK.

I'd probably try cleaning the MAF with some aerosol MAF cleaner, too.

Thanks mate,
Re the 02 graph.The scale above seems to be showing what happens every 20 seconds.
Shouldn't the volts(?)go up and down every second as opposed to up and down say once every ten seconds,ie shouldn't the 02 graph be a lot livelier than what is shown?
I'd convinced myself one 02 sensor was screwed so i've bought one and i'll try that this Friday.The same day I've her booked to go on a rolling road.
Regards the .csv file, I've tried loading it on here but I get a fatal error code on here when trying to load it on here-I suspect the file is too large.
I'll go for another shorter drive and data log again.
I'm also on the case re the short term fuel readings. I can read it on the Diablo sport but can't show it as a graph just yet.
Thanks for all your help (and patience) so far.
Cheers

 

[mcstang]

Look here. I did a quick google search and maybe this will help you figure out what parameters to log.

http://www.svtperformance.com/forums/tuning-la-carte-375/813055-useful-diablo-predator-table.html

Cheers Geordie,
Yeah, I've got all that; the trouble is, I don't know what the hell it all means

 

[RLF9409]

[/URL][/IMG]

Here's the MAF

Still trying to suss out that live thingie.
Let me know what else you need.

John

Open the folders on the left of this screen for the fuel and spark and check the boxes for the long term and short term for both banks. Also for the spark check the box for spark advance.
short term trims bank 1
short term trims bank 2
load
fuel pump duty cycle
fual rail pressure drop across injector
Rpm

 

[mcstang]

[/URL][/IMG]


Half a job as I can't see any reference to short term trims.
Pretty hard to read with all those different shades of green and I'm still working on the .crv file