misfire, black smoke, rich exhaust, hydrolock
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Cl65 AMG
misfire, black smoke, rich exhaust, hydrolock
Hello,
2005 CL65 210,000 miles.
I had a small coolant leak at a heater hose in the back of the engine in the middle below or even with the intake manifold. I replace the hose and test drove the car. Ran great but the next morning I noticed the sound the starter/engine sounded different, however the engine started and ran fine for a minute or so then began to misfire and blow a huge cloud of black smoke along with a strong gas smell. I shut the engine down and tried to restart the engine and it cranked less than one rpm before it stopped like it hit a wall. The engine hydro-locked with gas. ?????
So this happened last month and I didn't have time to get into the problem.
First thoughts are fuel getting into the engine in volumes higher than expected
engine oil diluted via gas thus the change in the sound of the starter/crank rythm.
So at this point the codes are related to misfire
I did replace the coils but they have a ton of miles on them as well.
I don't think theres a issue with the coils
Maybe
1 injectors sticking on
2 Pressure regulator ruptured
3 ????? Sure there's a lot more that could be skewed
Any inputs ???????? Ideas ?????
2005 CL65 210,000 miles.
I had a small coolant leak at a heater hose in the back of the engine in the middle below or even with the intake manifold. I replace the hose and test drove the car. Ran great but the next morning I noticed the sound the starter/engine sounded different, however the engine started and ran fine for a minute or so then began to misfire and blow a huge cloud of black smoke along with a strong gas smell. I shut the engine down and tried to restart the engine and it cranked less than one rpm before it stopped like it hit a wall. The engine hydro-locked with gas. ?????
So this happened last month and I didn't have time to get into the problem.
First thoughts are fuel getting into the engine in volumes higher than expected
engine oil diluted via gas thus the change in the sound of the starter/crank rythm.
So at this point the codes are related to misfire
I did replace the coils but they have a ton of miles on them as well.
I don't think theres a issue with the coils
Maybe
1 injectors sticking on
2 Pressure regulator ruptured
3 ????? Sure there's a lot more that could be skewed
Any inputs ???????? Ideas ?????
Thread Starter
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Cl65 AMG
I did smell a lot of gas in the oil, however when I ran the engine it sounded good. Well, as good as a 12 cyl running on 8 cyl's. The coolant leak was hard to reach, so I put a thick pad on the top of the engine as so not to brake anything. I could have damaged something and there were a lot of vacuum/pressure lines down in the area I was working. Could have cracked one, just not likely that would cause this. 
A car with over 210 k should be done but the 65 ran very well prior to this issue.
Can anyone provide a screen shot of engine sensors key/ignition on engine not running ???? I then can compare readings to which are somewhat fixed.
A car with over 210 k should be done but the 65 ran very well prior to this issue. Can anyone provide a screen shot of engine sensors key/ignition on engine not running ???? I then can compare readings to which are somewhat fixed.
Thread Starter
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Cl65 AMG
Thanks for the input ! 
I do think it could be a injector stuck open. I think I could isolate the fuel system and see if pressure readings drop.
I doubt it's only one injector but, I'm an ex Tune-up & Drive-ability tech mostly for GM cars and trucks. The issue seems worse than one cylinder. Don't know if the extra fuel could migrate to other cylinders. Surely could be one injector. My mind is leaning toward an issue with the injector control or fuel pressure regulator. (ruptured diaphragm vacuum sucking fuel directly into the intake manifold) The volume of fuel seems greater than from one injector. I would love it to be something simple like the above mentioned.
Can anyone provide a screen shot of engine sensors key/ignition on engine not running ???? I then can compare readings to which are somewhat fixed.
I do think it could be a injector stuck open. I think I could isolate the fuel system and see if pressure readings drop.
I doubt it's only one injector but, I'm an ex Tune-up & Drive-ability tech mostly for GM cars and trucks. The issue seems worse than one cylinder. Don't know if the extra fuel could migrate to other cylinders. Surely could be one injector. My mind is leaning toward an issue with the injector control or fuel pressure regulator. (ruptured diaphragm vacuum sucking fuel directly into the intake manifold) The volume of fuel seems greater than from one injector. I would love it to be something simple like the above mentioned.
Can anyone provide a screen shot of engine sensors key/ignition on engine not running ???? I then can compare readings to which are somewhat fixed.
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Benz
I've seen the voltage transformer in the middle of the engine cause cylinders to not fire and the injectors being still on pumping raw fuel thru the exhaust. So maybe your issue is similar. And there is not fuel pressure regulator that could be causing this on your set up just to save you the time.
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Thread Starter
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Cl65 AMG
I've seen the voltage transformer in the middle of the engine cause cylinders to not fire and the injectors being still on pumping raw fuel thru the exhaust. So maybe your issue is similar. And there is not fuel pressure regulator that could be causing this on your set up just to save you the time.
Clear something up for me ? The fuel filter on my car has a fuel pressure regulator built into it. It has a what I thought was a vacuum line that leads
to the engine. I agree the above mentioned controller could be at fault. I think that will be testable.
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Benz
No that is not a pressure regulator. The pressure I'd regulated by the fuel pressure sensor that it is in one of the feed lines in the back there at the filter, and trace the wires from pump to this square cube module. The duty cycles the pump to maintain the set pressure, which on the 65s it's around 55 if I remember right. You want to make it easy, spend 45 mins pull both coils and all the plugs. See what bank your issues is with and for fuel contamination, then do a quick compression test. While you've got the coil and plugs out, flip the coils upside down plug them in and put the plugs in the tubes and crank it, you'll see if any other the cylinders aren't firing.
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Cl65 AMG
Thanks,
I do know what cube your referencing, I will connect a pressure gauge and see if it bleeds off fast once the pump turns off. Then I will unplug the injector controller and the injectors and watch the pressure. If it bleeds off fast its likely an injector. Then I can open up the coils, plugs and injectors. Compression test is also on the menu.
I do know what cube your referencing, I will connect a pressure gauge and see if it bleeds off fast once the pump turns off. Then I will unplug the injector controller and the injectors and watch the pressure. If it bleeds off fast its likely an injector. Then I can open up the coils, plugs and injectors. Compression test is also on the menu.
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Cl65 AMG
So I disconnected the module which sits atop the intake, said to control the injector operation. Cranked the engine and after taking into account any left over fuel in the cylinder it still hydro-locked as it did before during cranking.
Likely the fuel is still getting into the cylinder with out the help of the engine management system.
Next likely remove the injector rail and see how they work in real life LOL
Likely the fuel is still getting into the cylinder with out the help of the engine management system.
Next likely remove the injector rail and see how they work in real life LOL
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Benz
Dude, that module doesn't control or fire the injectors, it handles the coils and relays information to the ecu. The ecu controls the injectors. Are you sure you were a diagnostic tech? Because your going at this thing like someone who doesn't know anything about cars! Not trying to be offensive but it's archaic what your doing to the poor car lol! The rail comes out easy, the coils, come out easy, and an SDS is cheap and easy to use.
Thread Starter
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Cl65 AMG
Dude, that module doesn't control or fire the injectors, it handles the coils and relays information to the ecu. The ecu controls the injectors. Are you sure you were a diagnostic tech? Because your going at this thing like someone who doesn't know anything about cars! Not trying to be offensive but it's archaic what your doing to the poor car lol! The rail comes out easy, the coils, come out easy, and an SDS is cheap and easy to use.
do you have a service manual ? Where might I find info about the engine management system ? I'm working blind on this car. Here is a 1972 Porsche 914 with an LS6 a G-50-6 speed and a complete 2003 911/996 front and rear suspension Oh it has electric power steering along with a ton of body stiffening.
all built in my garage by me want to race ?
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Cl65 AMG
So I was able to do some more testing which led me to removing the injectors.
I found at least one injector stuck open.
I'm going to replace the plugs and the injectors.
Any recommendations with respect to the injectors ????
I see Bosch makes replacements ???
I found at least one injector stuck open.
I'm going to replace the plugs and the injectors.
Any recommendations with respect to the injectors ????
I see Bosch makes replacements ???
Thread Starter
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Cl65 AMG
Thank's for the reply, I was able to get a new set and am hoping to get the car back on the road soon.
I have 210,000 miles on this 2005 CL65 and don't know how long this engine will last. I have said this before but my rule is to always start the car and keep the rpm low (<2500 rpm) until warm up is complete. Change the oil and filter between 3&4 thousand miles.
It can't run forever so I need to start planning for a replacement / rebuild.
My history tends to lean to a GM LS7 but who knows what it will be.
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Cl65 AMG
I did get the 12 injectors installed and started the engine. the engine didn't run well, had misfires galore, but did run different / better without an injector stuck open in the #3cyl.
The plugs likely need to be replaced/cleaned as there was likely a ton of gas pumped into the intake. The side the injector stuck open smoked a ton, mostly all left over gas in the exhaust system. Theres likely a lot of gas hanging around in the engine.
As for any damage to the engine, seems the old girl (210k-miles) is hanging in, no bent rod or washed out rings.
The engine is in a happy place here, we moved from Southern Ca. to north/west Washington state cool air intake temps
Tomorrow I will inspect the spark plugs and change the oil, along with try to
dry out the intake system.
Then put it back together and it should be good to go
The plugs likely need to be replaced/cleaned as there was likely a ton of gas pumped into the intake. The side the injector stuck open smoked a ton, mostly all left over gas in the exhaust system. Theres likely a lot of gas hanging around in the engine.
As for any damage to the engine, seems the old girl (210k-miles) is hanging in, no bent rod or washed out rings.
The engine is in a happy place here, we moved from Southern Ca. to north/west Washington state cool air intake temps
Tomorrow I will inspect the spark plugs and change the oil, along with try to
dry out the intake system.
Then put it back together and it should be good to go
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W215 CL65
I did get the 12 injectors installed and started the engine. the engine didn't run well, had misfires galore, but did run different / better without an injector stuck open in the #3cyl.
The plugs likely need to be replaced/cleaned as there was likely a ton of gas pumped into the intake. The side the injector stuck open smoked a ton, mostly all left over gas in the exhaust system. Theres likely a lot of gas hanging around in the engine.
As for any damage to the engine, seems the old girl (210k-miles) is hanging in, no bent rod or washed out rings.
The engine is in a happy place here, we moved from Southern Ca. to north/west Washington state cool air intake temps
Tomorrow I will inspect the spark plugs and change the oil, along with try to
dry out the intake system.
Then put it back together and it should be good to go
The plugs likely need to be replaced/cleaned as there was likely a ton of gas pumped into the intake. The side the injector stuck open smoked a ton, mostly all left over gas in the exhaust system. Theres likely a lot of gas hanging around in the engine.
As for any damage to the engine, seems the old girl (210k-miles) is hanging in, no bent rod or washed out rings.
The engine is in a happy place here, we moved from Southern Ca. to north/west Washington state cool air intake temps
Tomorrow I will inspect the spark plugs and change the oil, along with try to
dry out the intake system.
Then put it back together and it should be good to go
Any updates? Hoping your car came out in the end. Did you do any compression tests etc.
Best,
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Cl65 AMG
injectors. Some how i got a set for a newer CL65 M275 engine. After installing the injectors and running the engine I felt maybe a new set of
plugs would be the next step. So pulling and inspecting them they were all wet and black. I installed a new set of plugs and the engine ran perfect for a minute, than began to pile up misfires. I knew things were far better but just the misfires and rich exhaust numbers along with a sulfur smell just made me check the basics. First all connections, vacuum lines etc. The last thing I did was check part numbers, well I have the correct set coming in the next week or so.
I'm thinking the correct parts will get me back on the road.
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Cl65 AMG
I'm still waiting on the correct injectors (factory Bosch). The parts folks pushed back the shipment 2 times. May 22 is the next shipment date, so
I hope they will be at my place soon....
I hope they will be at my place soon....
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CL65
That stinks, it is becoming harder and harder to get older parts. MB doesn't care to be in the parts business. They sit on back order until there's a demand to make a certain amount. They prefer you just buy another $200k car. Hanging on to these cars means retro fitting alternate parts or having original parts rebuilt/refurbished with long wait times. Good luck, hope to see you back up and running.
MBWorld Fanatic!
Joined: Jan 2011
Posts: 1,181
Likes: 59
CL65
That stinks, it is becoming harder and harder to get older parts. MB doesn't care to be in the parts business. They sit on back order until there's a demand to make a certain amount. They prefer you just buy another $200k car. Hanging on to these cars means retro fitting alternate parts or having original parts rebuilt/refurbished with long wait times. Good luck, hope to see you back up and running.
Thread Starter
Senior Member
Joined: Jul 2011
Posts: 386
Likes: 12
Cl65 AMG
That stinks, it is becoming harder and harder to get older parts. MB doesn't care to be in the parts business. They sit on back order until there's a demand to make a certain amount. They prefer you just buy another $200k car. Hanging on to these cars means retro fitting alternate parts or having original parts rebuilt/refurbished with long wait times. Good luck, hope to see you back up and running.
JUST HAVE TO SAY IT'S SO SO SO NICE TO BE BACK IN THE CAR AFTER 3 MONTHS SCREWING AROUND. I WAS SENTENCED TO DRIVE A 2007 CAMRY. FYI
Last edited by driveability; Jun 1, 2017 at 04:23 AM.
