Causes of running rich

[kieren1234]

Hi all, could someone list the possible things that can cause the car to run rich i.e vaccuum leak etc

I know it could turn into a lengthy list i just want to start troubleshooting.

[mikeyb10supra]

Check your 02 sensor, also running excessively lean can cause the ECU to overcompensate and run rich....do you have a wideband?
Also check temp sensors, if the ECU see's the car as being cold it will run rich

[kieren1234]

The car is an na-t and runs about 9.5 afr's on idle constantly from first start to fully warmed up so you could be right about the temp sensors. Where abouts are they??

Many thanks.

[kieren1234]

O2 sensor is brand new too.

[kieren1234]

Does anyone know the location of the sensors please???

[kieren1234]

Update, have changed the coolant temp sensor (one with the two wires) and having the same problem with it running that rich it dies after so long.

Anything else i can rule out of the equation??

[kieren1234]

I have also tried a friends ecu, map sensor, and 2 different known working e-manages but nothing again.

I have re wired the e-manage twice but still nothing. The car doesnt change how it runs when i make changes on the e-manage like trimming fuel out or increasing the injector size from 330 - 440.

I dont think the problem lies with the injectors or resistor box as it was running pig rich to begin with.

I can get it started if i only plug 4 of the injectors in, then when its running plug the other two in. But then just runs majorly rich contantly at about 9.5 afr's on idle.

I will gladly send over £50 to whoever sorts the problem as it has caused me so much bloody stress and sleepless nights thinking what it could be :(:(:(

[Ryan.G]

Ok it sound like all the injectors have a 12v feed going to them so i would suggest checking the 6 injector feeds which go back to the ECU to tell them to open. If one of them is grounding out somewhere then it will be opening that injector 100%.

Do a continuety test back from each injector plug to the ecu and it should not have any resistance.

If that is fine, Check your Fuel pressure and that the injectors are actually low impendance.

[kieren1234]

Hi Ryan. The injectors are from a mkIII Turbo and i have an aftermarket resistor pack. The car was running silly rich before i even installed these so im sure that fitting these was not the problem. Could you elaborate on how i would check that none of the wires are shorting and opening the injector 100% because what you say makes sense why it would be running so rich.

[TrickTT]

Does it only run rich on tickover, or under load as well? If its just at idle, check the idle air control valve at the back of the manifold.

[kieren1234]

It runs rich throughout the rev range on standstill.

When under load it will run rich untill it just begins to come on boost when it beginds to go lean (have not tried WOT or high rpm on boost)

Idle is when it runs the richest with about 9.5 afr's.

How do i check the iacv without getting a new one??

[kieren1234]

Bump

[kieren1234]

Ok it sound like all the injectors have a 12v feed going to them so i would suggest checking the 6 injector feeds which go back to the ECU to tell them to open. If one of them is grounding out somewhere then it will be opening that injector 100%.

Do a continuety test back from each injector plug to the ecu and it should not have any resistance.

If that is fine, Check your Fuel pressure and that the injectors are actually low impendance.

Ok, i have checked the resistance AT the ecu by putting one probe of the multimeter on the wire that goes from the injector to the ecu, and the other probe on one of the black/orange wires and each injector measures 1.90 ohms.

Im assuming this is wrong.

This was all done with ignition turned to ON.

[Tricky-Ricky]

You need to do the continuity test with the ign off and preferably with loom disconnected first, I'm presuming that the resistance thats showing is from the EMU being in the circuit, however if they all read the same then i guess that rules out a short on one of the wires.
The other problem that make it difficult to test is that you have both an emanage (but i think you have now eliminated that by switching for another?) but the wiring still could be wrong, and also the injector resistor pack, and really these should be tested separately, the other problem is that you can't AFAIK electronically test an injector for being stick open.

[kieren1234]

Thanks Ricky. I am again, going to re wire the e-manage and check its connections as it still seems wierd that the car does not chenge at all when making changes and exporting it to the main unit.

There is definately not a short on one of the injectors as they all show the same resistance.

I think the injectors and resistor pack are just adding to the orininal problem of running rich. (was running rich with 330'sa so obviously going to run even richer with the 440's)

i am also going to cvheck all the vaccuum pipes with soapy water whilst the car is running, to rule out any vaccuum leaks (allthough im not sure this would make the car run that rich).

[kieren1234]

You need to do the continuity test with the ign off and preferably with loom disconnected first, I'm presuming that the resistance thats showing is from the EMU being in the circuit

How do i do this continuity test??

Yes the EMB is in the circuit when i tested the resistance.

[Tricky-Ricky]

How do i do this continuity test??

Yes the EMB is in the circuit when i tested the resistance.
Not quite sure how you have tested already?

If you undo the small bolt on the multi connector to the ECU and disconnect from the ECU, you will need a pin out diagram to locate the correct wires, which i,m presuming you already know? and then disconnect the injector plugs and put one meter probe on the appropriate injector plug and the other on the multi connector at the correct wire, and check the resistance, this will at least tell you if there is a short in the wiring.

I take it you have checked the injectors to make sure they are high or low impedance type?

[kieren1234]

Not quite sure how you have tested already?

If you undo the small bolt on the multi connector to the ECU and disconnect from the ECU, you will need a pin out diagram to locate the correct wires, which i,m presuming you already know? and then disconnect the injector plugs and put one meter probe on the appropriate injector plug and the other on the multi connector at the correct wire, and check the resistance, this will at least tell you if there is a short in the wiring.

I take it you have checked the injectors to make sure they are high or low impedance type?

So i disconnect the ecu plug that is held in with 10mm bolt. Put one of the the multimeter pins to that end on the loom, and the other multimeter pin to the wire at the injector side??

I will go do that now.

The injectors are from mkIII Turbo hence the need for the resistor box to change the impedence.

[kieren1234]

Ricky, i have checked the resistance exactly how you said and each get a reading of 0.00 resistance so this is now ruled out of the equation. Perhaps we may be focusing too much on the injectors as it could be a number of different things (what these are i dont know)

Help is greatly appreciated so far!

[kieren1234]

Any more ideas folks??

[Ian C]

OK some of this may have been covered already but I'm going to brain dump:

1) Go back to the stock injectors. If you had a running rich problem with those, you were I'm afraid a bit of a fool to stick bigger ones in and hope it all worked :) Going back to stock rules out it just being the bigger injectors and it rules out issues with the resistor pack. With the smaller ones in you also stand a better chance of diagnosing the problem without turning your engine into a 3.1l block with 2.9l pistons ;) Yes it may be some annoying wiring but this far along the tearing-your-hair-out path it's necessary.

2) It's not going to be a sensor issue with regards to intake temps and water temps - they are trim maps only, there is no way they could get an engine fuelling out of the range of closed loop and then all the way down to 9.5:1afrs. What is the lowest your O2 sensor can read? Is it in fact 9.5:1afrs? Also, does your O2 sensor ever show anything different - e.g. switched on without the engine running it should show a lean value as there is just air in the exhaust (you may need to turn the engine over with the fuel pump disconnected to muck out the exhaust first to test this). Always check your sensors aren't lying to you.

3) I'm sure I asked this before, but can you datalog the stock injector durations with the E-Manage. This is an invaluable tool for diagnosing what the problem is. A warm idle should be about 2.4ms of duration - if it is showing this you have fuel pressure problems, sticking injectors, or an earthing fault thats opening them. Or the impedance is wrong. If the duration is much higher than 2.4 then the ECU is getting something wrong somewhere, a rogue input for example.

4) Check the injectors impedance by measuring the resistance across its terminals. Check the resistor pack impedance by measuring its resistance across the input and one output. You should achieve 12ohms if you add them both together. More than this and youve got a resistor pack when you shouldn't have.

5) Check with the E-Manage what it thinks your MAP sensor is showing. I know this is complicated by the whole MAF/MAP NA to turbo thang but your airflow system still has to work in some fashion. Whatever you are using to tell the STOCK ECU what the airflow into the engine is needs checking. If it isn't wired right or is broken, or it's a MAP sensor with its hose off, you'll probably be sending the ECU an atmospheric signal. As far as the ECU is concerned, that means "full load" to an NA, so the fuelling will be off the clock.

6) Some other things to check quickly with the E-manage monitoring/datalogging:
Throttle position
RPMs
Ignition timing
Airflow voltage in vs airflow voltage out vs %age of airflow removed

Until you come back with the answers to some of these, especially the readings off the E-Manage, there is no point expanding further :) See what you get.

-Ian

[kieren1234]

Thanks for that Ian. I will get straight onto it tomorrow morning and report back.

Many thanks.

[kieren1234]

Ian C, i have gone back to the stock injectors and the car now starts everytime but as before, runs pig rich again.]

I will be able to check the other things you have mentioned on the weekend. Many thanks.

[kieren1234]

Ian C i have been and done some datalogging and hopefully these answers/finings will help you to help me :)

1. I now have the stock 330's in there and i agree i was silly to put bigger injectors in when i knew it was running rich before (although in my defence i did think the e-manage would be able to trim the extra fuel flow).

2. I had already put in a new coolant temp sensor and like you have said, had no impact on the problem. The car is definately running 9.5 afr's, the wideband will read as low as 7.4.

3. Yes you can log the injectors and here are my findings:

On Idle the injectors are 6.7ms of duration:

http://i169.photobucket.com/albums/u215/kieren1234/3333333.jpg

When revving the car to 1000rpm injectors are 13.1ms of duration:

http://i169.photobucket.com/albums/u215/kieren1234/22222222.jpg

4. I will have to check the impedance once i get my multimeter back from friend this weekend.

5. I ave checked the MAP sensor and the pipe on it is brand new silicone, and the electrical connection is secure. Please see above pics of the input and output of the sensor.

6. Throttle position seems to be ok
Rpm coincide with what is displayed on the dash
Ignition timing is done by moving the distributor on the N/A and e-manage cannot control this.
Airflow equation please see above pics.

[kieren1234]

Bump.

[Ian C]

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

[kieren1234]

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.

[Ian C]

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

[Ian C]

"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

[Ian C]

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

[kieren1234]

Cheers for that input Ian. I shall give everything a go this weekend and hopefully it will sort it. If not i will await your return and bombard you with questions again :p:p

Many thanks!!

I have tried his MAP sensor already and is the same.

[kieren1234]

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.

[Swampy442]

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.

[kieren1234]

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

[Tricky-Ricky]

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.

[kieren1234]

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

[kieren1234]

Here is the cold start log mate. Couldnt do it as long as id have liked as the laptop cut out but you get the general idea hopefully.

Please let me know your thoughts.

[steve spedd]

what software do you use to view that file mate?

[kieren1234]

E-manage support tool. Open the support tool, then go to data analysis button along the top toolbar. Then open the file and you can view it.

[steve spedd]

fair play mate, not got that on works comp... i think the discs are at your gaff.... ;)

[kieren1234]

Hopefully someone can have a ook at this shortly and help me diagnose the problem :(:(

[Tricky-Ricky]

Kieren can you re attach that file and make sue its saved as a GSC file, as i can't open it with the emanage software.

[kieren1234]

Will try it now mate.

[kieren1234]

How do i do that Ricky. I may have to go and do another datalog.........

[kieren1234]

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

Many thanks.

[Tricky-Ricky]

Well emanage blue uses GSC to save data log files so it should do it automatically, cant understand why yours are LGI maybe the file compression has changed the format.

[kieren1234]

Every time i save the file it says save as, and it is already saying GSCLOG file.

when it saves it to desktop it saves two files, an LGI file, and an LGD file???

Am i doing something wrong??

[Tricky-Ricky]

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??

[kieren1234]

May be that the software version is different to yours. Try this. Save these two to the desktop then try opening them when the e-manage software is on and then going to the data analyser section.

On my PC it lets me open the LGD file now.

[steve spedd]

cant you just do a print screen or is it not a graph buddy?

[kieren1234]

FAO - TrickyRicky.

See if that works doing that. Thanks.

Steve, not like that.

[Tricky-Ricky]

At last! unfortunately there is nothing that really says anything, other than there is an initial -20% out of the airflow map? but this returns to normal, the duty cycle drops as it should during warm up, although you didn't record for long, but the duration remains the same, are you sure there is no adjustments to the front panel rotary switches?

[kieren1234]

Sorry Ricky, that airflow adjustment was me changing it back to 0 on the front panel on the first switch. they were all put to the bottom. As you could see it still didnt make any changes from moving it back to 0.

Im assuming the injector durations should alter then?? But mine seem to be stuck at 6.7 ms.

[Tricky-Ricky]

Did you say that the ECU has been changed? as i am starting to think there may be a problem with the output stage of the injector drivers.

I also wonder if it also could be down to the intake temp sensor, but I'm not sure how the ECU behaves if the sensor is faulty.

[kieren1234]

Yes Ricky, it is the stock ECU in there at the moment but i have tried my friends ecu before and im certain it had no affect at all and was still running rich HOWEVER, this was when my innovate was playing up and only displaying 7.4 afrs.

I will have to try his ECU again one time and check the durations on the e-manage software which is what i should have done before but ddnt know about this at the time.

[kieren1234]

Right, i am getting a friends n/a ECU on Tuesday ready to try it on wednesday so i think it will bebest to just leave it for now and then i will report back with the results. At least it rule another thing out of the equation if this is not causing the problem...

[steve spedd]

cost you a pint mate ;)

[Ian C]

Well emanage blue uses GSC to save data log files so it should do it automatically, cant understand why yours are LGI maybe the file compression has changed the format.

:taped:

At last! unfortunately there is nothing that really says anything, other than there is an initial -20% out of the airflow map? but this returns to normal, the duty cycle drops as it should during warm up, although you didn't record for long, but the duration remains the same, are you sure there is no adjustments to the front panel rotary switches?

:taped:

Did you say that the ECU has been changed? as i am starting to think there may be a problem with the output stage of the injector drivers.

I also wonder if it also could be down to the intake temp sensor, but I'm not sure how the ECU behaves if the sensor is faulty.

:taped:

Honestly I'm going to have to start contributing to E-Manage threads again soon for the good of the community no matter how much it upsets you.

-Ian

[Tricky-Ricky]

Please feel free Ian, the factual content of what you say has never given me a problem.
Since you where already contributing, i see no reason why you shouldn't continue.

I haven't used blue EM for quite a while and had to reload the software to try and display the file, and the first three files wouldn't open, or just fire up the EMU software,

I was under the impression that the duty cycle reduced as the std ECU came off warm up correction? but he duration didn't change, which presumably is why it has rich AFRs?

For my third answer, dose the N/A have a air temp sensor? and whats you opinion