Leaking injectors
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C63s Cabriolet, BMW M4, Civic
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Moreover if it leaks long enough and floods the combustion chamber you have a hydrolock. Not sure if anyone remembers the AutoVlog guy from YouTube. He used to have a C205 and hydrolocked it during a rainstorm. I'm not watching his channel, but he came up in my feed a while back. He subsequently bought a W204 C63 and hydrolocked it again, this time due to a leaking fuel injector. Engine stalled while driving. He was lucky and nothing got bent. All to say I haven't seen this to be an issue with the M177/M178 engines, but leaking fuel injectors is not unheard of. Number 1 reason for fuel injectors to clog is bad fuel quality or carbon build up. Hope you are using only Top Tier fuel, which has the necessary detergents to keep the injectors from clogging and subsequently leaking, and you frequently drive long distances to get the engine and oil fully warmed up and give it the beans once in a while so it sees redline. As they say, one redline a day keeps the mechanic away 
.
.
Last edited by superswiss; Apr 17, 2023 at 08:57 PM.
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I've had one leaking injector on Cylinder 6 which will cause temporary compression loss. It's the achilles heel of the M177 so if you can catch it early you're fine.
To catch it early you'll notice not only the Check Engine Light but your ECO start stop button won't illuminate green anymore and be totally disabled. Another reason why you shouldn't be tuning this function out. Sadly, a lot of tuners will tune it out and some will never know until it's too late. Couple of guys here in Sydney grenaded their M177's due to injector playing up
To catch it early you'll notice not only the Check Engine Light but your ECO start stop button won't illuminate green anymore and be totally disabled. Another reason why you shouldn't be tuning this function out. Sadly, a lot of tuners will tune it out and some will never know until it's too late. Couple of guys here in Sydney grenaded their M177's due to injector playing up
Last edited by Jimmy_c63s; Apr 18, 2023 at 05:38 AM. Reason: Forgot who it was
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C63 S Coupe
I've had one leaking injector on Cylinder 6 which will cause temporary compression loss. It's the achilles heel of the M177 so if you can catch it early you're fine.
To catch it early you'll notice not only the Check Engine Light but your ECO start stop button won't illuminate green anymore and be totally disabled. Another reason why you shouldn't be tuning this function out. Sadly, a lot of tuners will tune it out and some will never know until it's too late. I know of two guys here in Sydney who grenaded their M177's due to just one injector playing up and they both had the ECO start stop tuned out and ignored CEL's.
To catch it early you'll notice not only the Check Engine Light but your ECO start stop button won't illuminate green anymore and be totally disabled. Another reason why you shouldn't be tuning this function out. Sadly, a lot of tuners will tune it out and some will never know until it's too late. I know of two guys here in Sydney who grenaded their M177's due to just one injector playing up and they both had the ECO start stop tuned out and ignored CEL's.
Last edited by George_1992; Jun 28, 2023 at 06:11 AM. Reason: Pic removed
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2019 C63CS
Wondering what years. Looks like PFLs so far. The engine was brand new for the early years. The early models had engine mounts and e-diff issues as well. If the injectors were still this bad I'd expect tons of current AMGs with blown engines.
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In 3 years my pfl will be 10 years old so the very early models are getting on now 🙁
But there's tips and tricks that we can all share to minimize our downtimes for those who still want to run these cars and one of those tips are not to tune out the ECO Start/Stop as that little green light serves as a warning system if an injector is dying.
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You are right I've changed both front engine mounts, diff rebuild, and one injector on my old dinosaur not to mention the coil packs & all that.
In 3 years my pfl will be 10 years old so the very early models are getting on now 🙁
But there's tips and tricks that we can all share to minimize our downtimes for those who still want to run these cars and one of those tips are not to tune out the ECO Start/Stop as that little green light serves as a warning system if an injector is dying.
In 3 years my pfl will be 10 years old so the very early models are getting on now 🙁
But there's tips and tricks that we can all share to minimize our downtimes for those who still want to run these cars and one of those tips are not to tune out the ECO Start/Stop as that little green light serves as a warning system if an injector is dying.
i had my e diff replaced under warranty around 40,000 km so hopefully thats one thing i dont have to worry about
what made you change your engine mounts? What symptoms did you get? Thanks
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with my car close to 90,000 km now I feel like these topics are what i need to take notes on.
i had my e diff replaced under warranty around 40,000 km so hopefully thats one thing i dont have to worry about
what made you change your engine mounts? What symptoms did you get? Thanks
i had my e diff replaced under warranty around 40,000 km so hopefully thats one thing i dont have to worry about
what made you change your engine mounts? What symptoms did you get? Thanks
Nothing obvious at the start but thumping noises on takeoff and suspension always stiff if I put it in Sport mode and switch back to Comfort it wouldn't loosen up again
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2019 C63S Coupe
clogging and carbon build up,. Also part of the B Service includes VPS Fuel Injector cleaner $13.90 part# 891566. that just get put into the gas tank which should be a full tank o gas.
My car was running fine when I brought it in but after the Service it had felt more powerful smoother ride that was ready to really open up.
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W205 C63S T
I had one leaking on bank 2... no cel! no misifres.. no hickups... but still leaking... since pressure was dropping to quickly... plugs was black as fck on cyl 7....
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Its not a PFL or FL thing....injectors are the same.. and leaking injectors doesnt mean your engine is going to blow..... can be easily tested with some logging equipment and keep an eye on fuelpressure and when shutting the engine of how quickly pressure drops..
I had one leaking on bank 2... no cel! no misifres.. no hickups... but still leaking... since pressure was dropping to quickly... plugs was black as fck on cyl 7....
I had one leaking on bank 2... no cel! no misifres.. no hickups... but still leaking... since pressure was dropping to quickly... plugs was black as fck on cyl 7....
But yes as I said, injectors can get clogged due to bad fuel quality such as debris in the fuel or a driving style that promotes carbon build up, or not using Top Tier fuel.
Last edited by superswiss; Apr 19, 2023 at 12:22 PM.
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W205 C63S T
What I'm getting at is that parts constantly get revised over time in response to issues. Pretty sure the injectors today are not the same part as they were when the engine first came out. Same for the engine mounts and e-diff. They got revised to address the early issues.
But yes as I said, injectors can get clogged due to bad fuel quality such as debris in the fuel or a driving style that promotes carbon build up, or not using Top Tier fuel.
But yes as I said, injectors can get clogged due to bad fuel quality such as debris in the fuel or a driving style that promotes carbon build up, or not using Top Tier fuel.
HPFP has been revised on the FL models.. hence ending part nr on 501 instead of 401.. injectors have been the same from day one...
You cant compare theses injectors anymore to years ago... these babies run on around 200 bar pressure... thing s will just go eventually....
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Moreover if it leaks long enough and floods the combustion chamber you have a hydrolock. Not sure if anyone remembers the AutoVlog guy from YouTube. He used to have a C205 and hydrolocked it during a rainstorm. I'm not watching his channel, but he came up in my feed a while back. He subsequently bought a W204 C63 and hydrolocked it again, this time due to a leaking fuel injector. Engine stalled while driving. He was lucky and nothing got bent. All to say I haven't seen this to be an issue with the M177/M178 engines, but leaking fuel injectors is not unheard of. Number 1 reason for fuel injectors to clog is bad fuel quality or carbon build up. Hope you are using only Top Tier fuel, which has the necessary detergents to keep the injectors from clogging and subsequently leaking, and you frequently drive long distances to get the engine and oil fully warmed up and give it the beans once in a while so it sees redline. As they say, one redline a day keeps the mechanic away .
.
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I had three leaking on bank 1... car started crappier, slight misfires occasionally... car was hesistant on full throttle... car was also fuming on full throttle out of the exhaust.. so if people dont feel that.. they are stupid!
fuel pressure dropped quicker then a blink of an eye when engine shutting off....
the last one one on cyl 7 , was just one... car runs perfectly fine!! couldnt be noticed for now.... i did plugs and saw it... plug was all black.... and had error message fuel presssure was low... did live log and it lost pressure way to quick when engine shutting off..
So if your having a leaky injector it doesnt mean your gonna experience the big boom.....
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Lol
I had three leaking on bank 1... car started crappier, slight misfires occasionally... car was hesistant on full throttle... car was also fuming on full throttle out of the exhaust.. so if people dont feel that.. they are stupid!
fuel pressure dropped quicker then a blink of an eye when engine shutting off....
the last one one on cyl 7 , was just one... car runs perfectly fine!! couldnt be noticed for now.... i did plugs and saw it... plug was all black.... and had error message fuel presssure was low... did live log and it lost pressure way to quick when engine shutting off..
So if your having a leaky injector it doesnt mean your gonna experience the big boom.....
I had three leaking on bank 1... car started crappier, slight misfires occasionally... car was hesistant on full throttle... car was also fuming on full throttle out of the exhaust.. so if people dont feel that.. they are stupid!
fuel pressure dropped quicker then a blink of an eye when engine shutting off....
the last one one on cyl 7 , was just one... car runs perfectly fine!! couldnt be noticed for now.... i did plugs and saw it... plug was all black.... and had error message fuel presssure was low... did live log and it lost pressure way to quick when engine shutting off..
So if your having a leaky injector it doesnt mean your gonna experience the big boom.....
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W205 C63S T
Leaking injectors are easy to be diagnosed... pull plugs.. .have a look... if black ---> 90 % leaking injectors, car also started less aggresive then normal...
Also do a live log , pressure shouldnt drop quickly after turning off car... and youll get the low fuel pressure bank 1 or 2 and you cant erase code...
ive talked to a few specialists now and its a common thing with the "modern" injectors running at 200 bar .. . BMW has the same problems .with their ****ty injectors..
We have big plus... and that is that our injectors are used on all common normal MBs as well....!!
