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Causes of running rich


kieren1234

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OK, email me the datalog files as discussed over PM - be quick as I'm off to France on Friday for a long weekend ;)

 

Is the wideband still showing 9.5 AFRs even though there are smaller injectors in? If so that's odd but the fact it's still idling poorly and so forth means there is a genuine overfuelling issue.

 

That duration looks like the reason for it - 6.7ms :blink:

 

Is your NA a MAF based airflow system or a MAP one? Edit - it's MAP based :)

 

-Ian

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Yes its MAP based.

 

I will send the files through tonight when i finish work at 9 o'clock then if your off Friday.

 

I will check my friends injector duration on his na-t also to see if its a lot lower.

 

What would cause them to be this high Ian???

 

Will have to let you know about the wideband as it woudlt even idle with the bigger injectors so was unable to check, but definatelty saying 9.5 on idle with the stock injectors in.

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Aha if you have something to compare against that'd be very handy.

 

With the limited info from those two screengrabs and what I've been divining from datalogs of an NA-T conversion running 525cc injectors, I've figured this:

 

You are running about double the duty you should at idle (should be about 3.4ms) - check the warm idle duration of your freinds' NA.

The ECU is generating this too-high duty cycle so the injectors are only doing what is asked of them.

Therefore the ECU is getting a bad input somewhere.

It's not the RPM signal as you've tapped into that (IGF line) and it's reading correctly in the E-Manage.

It's not the MAP sensor reading wrong as I've compared the voltage signals of yours off those screengrabs to the NA-T and the Greddy sensor values tally with the MAP sensor values.

 

Not much left but I do notice that your throttle position is at 1% at idle - it is possible that your TPS isn't adjusted correctly and you are cosntantly off the "closed throttle" switch inside it and so you'll get an erratic idle. Don't think that'd cause big overfuelling though.

 

Get me a datalog of the cold start idle, for a good minute or so so I can watch it warm up - it may be that the temp sensor reading isn't reaching the ECU full stop and it is constantly on cold start.

 

Also I remember someone once having an overfuelling issue that was something to do with the starter motor setup, it was constantly telling the ECU the car was trying to start so it chucked buckets of fuel in...

 

-Ian

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"The cranking signal to ecu comes from the start relay,this could be isolated by pulling the 7.5 amp fuse -(starter),after the engine has started"

 

http://www.mkivsupra.net/vbb/showpost.php?p=225974&postcount=54

 

Looked on the electrical diagrams and it feed pin 77B "STA" of the ECU, so you could check that wire with a pin probe for 12v once the engine is running. Or just yank the 7.5amp fuse, see if it sorts it.

 

The cold start datalog will also help highlight this, it'll also show if the durations drop as the coolant warms up.

 

-Ian

 

hehe one side note in a four year old thread and I still remembered it, wish I could remember birthdays and so forth just as well

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Oh and if your friend is particularly generous you could borrow their MAP sensor for a test. I'm fairly sure it isn't that but it's a quick swap and worth a go. It does differ from the GReddy sensor at idle by a couple of PSI but even then it's the wrong direction so if anything you should be running leaner...

 

-Ian

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Right, i have looked into the problem and here is what i think it is:

 

My injector durations on the e-manage are showing over 6 miliseconds on a steady idle.

 

My friends na-t is showing around 2 miliseconds on idle.

 

Everything else has been checked so this could be the only thing left that i need to sort.

 

Does anyone have any idea on what affects the injector durations so i can start trouble shooting and hopefully sort it out??

 

Need to do this today ideally with working all week.

 

Many thanks.

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As Ian said, all the injector duration is sorted within the ECU, who mapped it? Thats the only way you can change the duration, by getting it reset. And its miliseconds, not seconds lol.

 

In the stock ecu?? as im only running an e-manage blue piggy back.

 

Cannot take it for mapping untill this is sorted.

 

Yeah ms, sorry :D:D

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Things to check that have an effect on this are, MAP sensor,or AFM, water temp sensor(already checked, and i believe the air temp sensor has also been eliminated?)

the emanage settings, and lambda sensor, which has also been checked? and injectors themselves, also checked, and vacuum leak?

So, my feelings are that its a bad signal to the ECU ie MAP sensor, have you swapped this out for a known good one?

as Ian says a log from cold start would help.

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Things to check that have an effect on this are, MAP sensor,or AFM, water temp sensor(already checked, and i believe the air temp sensor has also been eliminated?)

the emanage settings, and lambda sensor, which has also been checked? and injectors themselves, also checked, and vacuum leak?

So, my feelings are that its a bad signal to the ECU ie MAP sensor, have you swapped this out for a known good one?

as Ian says a log from cold start would help.

 

Hi Ricky, i have tried:

1. A known working map sensor

2. Water Temp sensor has been changed (the two wire one)

3. Air temp sensor - do you mean the intake air temperature sensor that is usually fitted into the stock airbox?? If so i dont think i have tried a different one of these so will order a new one to be on the safe side )

4. Cannot see any vacuum leaks, most of the vacuum pipes around the throttle body, inlet manifold have recently been changed for new silicone ones but did still have the same problem before and after.

5. I will go and do a log on the e-manage software now from cold start. How long shall i leave it running untill switching it off??

 

Many many thanks

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This should be it Ricky, let me know ASAP please. Really want to sort this and get it mapped.

 

Many thanks.

 

Still cant open it, i can only see it through the support tool, and if i try and open it through this i get (the old format was replaced with a new format. The airflow/throttle adjustment setting was initialised)!

 

and i just cant see it when i try to use the data log tool??

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