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Started to install the flex fuel kit and when I pulled the plugs out of the injectors I noticed the only the number 6 injector plug had a brownish liquid on it. Smells like gas mixed with oil? possibly because its brown. Ive had a random misfire here and there but they have always come up as pending in the torque pro app and never trigger the cel. Random meaning like every month or so. Only one time about 2 weeks ago the cel came on and the misfire code referred to number 7. Cleared it and havent seen anything come back.....
Any ideas? Im thinking the injector is going bad? They are Q5 also
Check your camshaft position sensor connectors, usually they get oil though them and it works its way though the harness. Check the M/E connector as well, it's probably full of oil.
Bentz, i've noticed the same thing on mine, but could never come to a conclusion as to where they came from.
I recently replaced all 8 injectors....when I'm next in that area, I'll take a look to see if the same issue exists.
Originally Posted by ItalianJoe1
Check your camshaft position sensor connectors, usually they get oil though them and it works its way though the harness. Check the M/E connector as well, it's probably full of oil.
wow really? I didn't even know that was possible...I'll check mine next time too.
Check your camshaft position sensor connectors, usually they get oil though them and it works its way though the harness. Check the M/E connector as well, it's probably full of oil.
Camshaft position sensors look fine.
M/E connector?
Originally Posted by Celicasaur
Bentz, i've noticed the same thing on mine, but could never come to a conclusion as to where they came from.
I recently replaced all 8 injectors....when I'm next in that area, I'll take a look to see if the same issue exists.
I know its possible for oil to wick through harnesses but I find it odd that a injector plug in the middle of the head has oil in it and not the plug closest to another sensor OR at the beginning or end of a wire harness
2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
So funny you posted this. I just had my intake manifold out today to finally do the 82mm throttle bodies (what a fukin PITA that turned out to be but more on that later) and like fifteen other things. I was going to post the same thing. 4 of my injector plugs were FULL of oil. I couldn’t figure out how that could have possibly happened but will keep an eye on it. The wire loom appears dry so I’m at a loss.
So funny you posted this. I just had my intake manifold out today to finally do the 82mm throttle bodies (what a fukin PITA that turned out to be but more on that later) and like fifteen other things. I was going to post the same thing. 4 of my injector plugs were FULL of oil. I couldn’t figure out how that could have possibly happened but will keep an eye on it. The wire loom appears dry so I’m at a loss.
Yes my harness is dry also. Its definitely gas (swabbed with cue-tip and it stinks like gas). But the brownish color has me convinced its oil mixed with gas. Especially since the hole in the manifold where the injectors go all have some oil in the opening. I figured the injector was going bad or on its way out. It almost seems like fuel/oil backed its way through the injector into the plug/connector. I just cant understand how that's possible.
The injectors get signal direct from the M/E (Motor Electronics, the engine computer). So oil getting into them has to come from there. That connector is getting oil in it somewhere else. Usually a cam position sensor or actuator leaks, pumps oil into the M/E's M connector, then it spreads to other things.
Yes my harness is dry also. Its definitely gas (swabbed with cue-tip and it stinks like gas). But the brownish color has me convinced its oil mixed with gas. Especially since the hole in the manifold where the injectors go all have some oil in the opening. I figured the injector was going bad or on its way out. It almost seems like fuel/oil backed its way through the injector into the plug/connector. I just cant understand how that's possible.
I know it's obvious, but what about the o-ring? Have.you replaced it? If it's shrunk or cracked perhaps a little fuel is getting past it when the pressure gets high? With the orientation of the plugs, fuel forced out from below could easily get up and in if it comes from the right angle.
The injectors get signal direct from the M/E (Motor Electronics, the engine computer). So oil getting into them has to come from there. That connector is getting oil in it somewhere else. Usually a cam position sensor or actuator leaks, pumps oil into the M/E's M connector, then it spreads to other things.
Ill have to keep digging and look further
Originally Posted by Doc Oc
I know it's obvious, but what about the o-ring? Have.you replaced it? If it's shrunk or cracked perhaps a little fuel is getting past it when the pressure gets high? With the orientation of the plugs, fuel forced out from below could easily get up and in if it comes from the right angle.
I replaced all the injectors and the new injectors have new o-rings also. The original o-ring in #6 looked fine but I did notice that the outside of the #6 injector was much dirtier then any other injector. Maybe it wasnt seated correctly which would make sense with your theory
^IDK if its happening with the new injector. I would have to pull the rail again. Drove the car last night after the flex install and she seems to be running fine....expect those crazy fuel trims. Just trying to figure out the whole "retune" idea after the install. Everything I read and what other people post suggest a tune is needed for the larger injectors. But on the other hand, I have eurocharged telling me that a retune is not needed. They said they have numerous cars with larger injectors and the flex kit without a retune and they are running fine.
I was unclear on that as well. EC told me the same thing but I've read several posts here that indicate a tune is necessary for larger injectors. Whats happening exactly as compared to the oem injectors? I can't run more than 60% ethanol (and even that puts me over 90% duty cycle) without upgrading so very interested to hear what you find out.
When I swapped my injectors the other day, I noticed the exact same thing. But, it isn't the first time I've noticed this... It happened on several of my cars over the years. After a quick Google search, I noticed that it happens across many different brands and manufacturers and model years... From what I've seen on other forums, rarely does it lead to anything catastrophic. More times than not, it's some dude doing basic maintenance and popping in new injectors, when he realizes he's got oil in the plug and makes a thread. The only thing I can think of is, the oil gets there because there's a lot of pressure in the combustion chamber, running anywhere from 600 - 7,000 RPMs at any given time and unburnt oil eventually finds its way through the seals in the injector and makes its way up to the connector
When I swapped my injectors the other day, I noticed the exact same thing. But, it isn't the first time I've noticed this... It happened on several of my cars over the years. After a quick Google search, I noticed that it happens across many different brands and manufacturers and model years... From what I've seen on other forums, rarely does it lead to anything catastrophic. More times than not, it's some dude doing basic maintenance and popping in new injectors, when he realizes he's got oil in the plug and makes a thread. The only thing I can think of is, the oil gets there because there's a lot of pressure in the combustion chamber, running anywhere from 600 - 7,000 RPMs at any given time and unburnt oil eventually finds its way through the seals in the injector and makes its way up to the connector
Well atleast Im not the only one....Still a mystery to me.
For the life of me, I can't understand how anyone could recommend larger injectors without a retune. Your fuel trims will change over time to compensate in closed loop conditions (idle, low demand situations like cruising and gentle acceleration) due to the upstream O2 sensor feedback. At WOT this car, like every other fuel injected vehicle I have come across, will ignore the O2 signal and default to the "high load" fueling map, which in your case will be based on the OEM injectors. Therefore, if the new injectors are capable of say, 30% more fuel delivery for a given duration time, then you will be using 30% more fuel at wide open throttle. This would be sub-optimal for power, fuel efficiency and emissions. Although running rich isn't quite as dangerous as going lean, I'd be concerned about catalytic converter life, as well as fouled plugs over time.
Unless of course the Flex fuel controller itself is somehow programmed for the change in fuel injectors. That should be able to solve this issue in theory. I just don't know if it has that capability.
ok I've just caught up with the thread (i was being naughty in a meeting and replying)
Balan is more or less right when he says that most fuel injected cars default to the open-loop/WOT injector map, ie it doesn't normally factor fuel trims. However some have the capability to use 02 feedback at WOT to help achieve the target AFR. I think ours is the latter.
For example, I haven't bothered yet to work on fine tuning of my fuelling because the lambda's are learning and keeping me in good-stead. However at WOT, it bases it's fuelling based on a target AFR (among other variables in tandem, like EGT) and quickly gets the fuelling spot on. I've increased airflow and efficiency on my engine a lot lately and so if the WOT fuel map was static, I'm sure that me commanding a different AFR along with lots more airflow with the original fuel map wouldn't be able to keep me from going lean and bang. (does that make sense? i'm really sleepy)
Therefore... 1) I should have read the thread (rather than skimming) before posting in #18 and 2) although not ideal, I can see why EC say to some of you guys that you can just run the larger injectors on the V5/6/7 tune that you already have.
Vladds - i know this is something that you know a lot about...chime in sir..
To be fair, I'm new to these particular cars, but every other vehicle I've come across using an O2 feedback loop for fuel trims operate that way, be it American, Japanese or German. And being that most engine management computers are made by only a handful of OEMs, I assume this behavior is typical. The only systems I'm aware of to date that have the capability of full range feedback operation are aftermarket standalone units like certain Haltech or AEM models. If there is indeed information that suggests that our ECUs operate differently, I'd definitely like to know more.
So the few resident gurus who state 24/7 closed loop are wrong?
Not sure who to believe anymore.
Yeah no, this is true to a large degree.
The reason why the open loop set up is different to closed is because things are happening much faster (usually high rpm) and the o2's wouldn't be able to react fast enough. On the newer cars like ours with much smarter ECU's and wideband lambda's, they can do much more.
But they of course as you know can't react fast enough to accommodate a superchargers airflow....that of course will require surgery to the fuelling at WOT.
If it is always in closed loop, then yes in theory the ECU would be able to adjust for somewhat larger injectors. I am suspicious though, as people with ROW boxes see changes in LTFT that seem to stick around. That suggests that the ECUs compensation for fueling is by fuel trims at best, rather than correcting the actual fuel tables.
04-07-2018, 03:25 PM
