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The crankcase vent system is not prone to plugging. If you have horrible sludge (ie. haven't changed the oil in 30,000 miles with non-synthetic) it's a possibility, but that would be far down on the list of possibilities, and it's not likely to cause rough running or no start, or to affect only one cylinder bank. Even if you have never changed the oil, cylinder wall damage would be a more likely cause of this issue than a plugged crankcase vent system.
Valve seals don't typically leak bad enough to cause any drivability issues, just oil burning, and they generally start to leak slowly. Badly worn valve guides can cause the seals to leak badly, and can cause misfires, but that's unlikely to suddenly affect an entire cylinder bank.
A wet compression test (with a very small amount of oil in the cylinder) is a quick way to see if rings are the cause of low compression, but it doesn't eliminate the need for a leakdown test unless the oil significantly raises compression (and if you add too much, it will raise compression regardless of the problem).
A bad ring doesn't explain the issue either. A compression ring problem can cause low compression on one cylinder. An oil ring problem can cause oil consumption on one cylinder. To duplicate your problem, you would need multiple catastrophic failures of multiple rings in multiple cylinders. That's unlikely in any engine, especially this one. Cylinder wall damage would be more likely, but it's still virtually unheard of on this engine and would still only affect one cylinder.
Well an update. Got the compression test kit.
Hooked up star and took pics of adaptation stuff and the freeze frame data(I can post it all if you want) and I also reset adaptation.
Just to test if it would start, I cranked it and I heard a metallic noise. It was like a duh duh duh duh duh all within the split second of cranking. Of course as soon as I heard it I stopped cranking
So something is obviously contacting from driver side cylinder bank.
I don’t think it’s safe to continue on with the compression test.
I guess I should take the valve cover off and see if there is any obvious damage up top.
Post the images of the adaptation data. A sound file of the noise would also be helpful. Before you keep cranking it, you might want to pull out at least one plug in each left side cylinder: a leaking injector could have filled one cylinder with fuel causing the noise. It's very hard to diagnose a noise without being there in person to hear it, but a sound file might help. Does the noise happen once per revolution of the engine or much faster? Can you tell if it's coming from the top or bottom of the engine?
Post the images of the adaptation data. A sound file of the noise would also be helpful. Before you keep cranking it, you might want to pull out at least one plug in each left side cylinder: a leaking injector could have filled one cylinder with fuel causing the noise. It's very hard to diagnose a noise without being there in person to hear it, but a sound file might help. Does the noise happen once per revolution of the engine or much faster? Can you tell if it's coming from the top or bottom of the engine?
The noise happened 5 times in one second of cranking. I was in the car so it was hard to determine the exact point of noise.
Should I get a sound file going? I can try cranking again and record it.
Would the fuel pool up and stay? Or would it leak down through the rings or evaporate.
I am almost sure there is fuel smell in the oil but not positive.
As for taking the plugs off I cannot for the life of me get the plug wires off.
Beru wires which when I pull on the rubber boot by hand it tears the rubber. It does not have a place to use the wrench tool. Metal jacket is recessed in the hole.
I'll try again tomorrow but idk.
Guys an update, fuel injector is stuck open.
Took the manifold off and noticed that fuel was pooled up on the intake valves.
To confirm it I cleaned it up and cranked it for a second(after pulling coils/wires/CPS harness)
Below is a video of the injector. Fuel rail gets pressurized and it all dumps out of the injector.
All the valves looked fine, pistons look fine; the noise I heard the other day from cranking is gone, it was just excess fuel being dumped in the cylinder.
Test the engine wiring harness for shorts. I already fixed one E55 with a stuck injector and burned engine ECU due to a failed engine harness- corrosion and insulation flaking off inside the harness underneath the supercharger- just like the old MB's from the 90's. However, the fact that you just worked on the injectors is also suspect.
Test the engine wiring harness for shorts. I already fixed one E55 with a stuck injector and burned engine ECU due to a failed engine harness- corrosion and insulation flaking off inside the harness underneath the supercharger- just like the old MB's from the 90's. However, the fact that you just worked on the injectors is also suspect.
I think the fact that I rebuilt the injectors and cleaned them may be the reason of its demise, or perchance the age and mileage has finally made them fail.
Either way I'm not chancing the rest; I just ordered all 8 injectors just in case.
With the injectors not getting power they should stay closed at rest correct?
So if fuel dumps out it has to be stuck open.
The plugs and harness all looks OK by eye, but I'll give it a more thorough examination tomorrow.
How did you go about testing the harness?
So that noise had to be liquid being compressed in the chamber and close to a hydro loc situation !! Thet would have really sucked. Glad you found your problem.
So that noise had to be liquid being compressed in the chamber and close to a hydro loc situation !! They would have really sucked. Glad you found your problem.
Correct, the noise was definitely the fuel. Luckily It did not happen during a pull.
BTW I just did a compression test. Info may be useless considering two things.
Cold engine and its a cheap Pittsburgh tester(bad reviews)
The tester has the Schrader valve at the gauge, hose is about 2ft long so it won't read the PSI correctly.
Many reviewers say their differences were huge from testing a good tool.
Glad to see you got it figured out. If you had a stuck open injector, you can't do a compression test now. the fuel will have washed all the oil off of the cylinder walls and compression will be very low (the oil helps the rings seal). Once you get it running again, then you can check compression if you want. Hopefully you didn't do any damage cranking it with too much fuel in the cylinder. Get it running then immediately change the oil: you will have a lot of fuel in your oil.
Also, harbor freight tools have their place, but they are not good when you need a precision instrument. A compression gauge that you cannot trust 100% is beyond worthless, and you definitely cannot trust that one.
Glad to see you got it figured out. If you had a stuck open injector, you can't do a compression test now. the fuel will have washed all the oil off of the cylinder walls and compression will be very low (the oil helps the rings seal). Once you get it running again, then you can check compression if you want. Hopefully you didn't do any damage cranking it with too much fuel in the cylinder. Get it running then immediately change the oil: you will have a lot of fuel in your oil.
Also, harbor freight tools have their place, but they are not good when you need a precision instrument. A compression gauge that you cannot trust 100% is beyond worthless, and you definitely cannot trust that one.
Makes total sense about the fuel washing the oil film. That would be why numbers are all over the place(coupled with cheap tool). I have ordered all injectors to be safe, should be here today or tomorrow.
It would be a good idea to put a little oil in each cylinder before I try to start the car when it’s all back together.
I think everything is fine, fuel injector didn’t stick open until I was putting around with no load on the engine. And I only cranked the engine 3 times or so for a second.
I may try spraying something into cylinder 5 for the carbon buildup. Any suggestions?
Makes total sense about the fuel washing the oil film. That would be why numbers are all over the place(coupled with cheap tool). I have ordered all injectors to be safe, should be here today or tomorrow.
It would be a good idea to put a little oil in each cylinder before I try to start the car when it’s all back together.
I think everything is fine, fuel injector didn’t stick open until I was putting around with no load on the engine. And I only cranked the engine 3 times or so for a second.
I may try spraying something into cylinder 5 for the carbon buildup. Any suggestions?
and oil is also ordered. I will change it ASAP
The wash down of oil film will only be in one cyl, the one with the open injector. That don't explain the wide spread numbers on the other cyl.
My money is on the gauge as well.
You could also use a leak down tester, to see how badly your cylinders or valve seats are.
The wash down of oil film will only be in one cyl, the one with the open injector. That don't explain the wide spread numbers on the other cyl.
My money is on the gauge as well.
You could also use a leak down tester, to see how badly your cylinders or valve seats are.
Well all the cylinders got washed from the multiple cranks enough to reduce compression. But yes I’d say there are other variables like the junk gauge and perhaps other spark plugs were loose from me checking them
Update. Replaced injectors and buttoned everything back. Poured oil down the intake valves and cranked it prior to start to get some lubrication going.
Car started up. Huge cloud of smoke. Like I dumped sea foam in the intake. Smoked for several mins
its all cleared up now and idles smoothly, at this point I think everything is good. Next step is changing oil. I will update when I start driving it
Update. Replaced injectors and buttoned everything back. Poured oil down the intake valves and cranked it prior to start to get some lubrication going.
Car started up. Huge cloud of smoke. Like I dumped sea foam in the intake. Smoked for several mins
its all cleared up now and idles smoothly, at this point I think everything is good. Next step is changing oil. I will update when I start driving it
Sounds like you got lucky, stuck injectors basically always have the same symptoms. Looks like I was a little premature with the bent rod thing lol but glad it worked out.
Sounds like you got lucky, stuck injectors basically always have the same symptoms. Looks like I was a little premature with the bent rod thing lol but glad it worked out.
Yes luckily it did not happen while the engine was under load. So im happy lol.
Update.
Got some drive time after doing an oil change.
Car runs great at WOT, I think there is more power now. Likes to roast the tires at quarter throttle now.
Small issue.
Car bucks while coasting at low RPM. Not consistently but it gets more consistent if it's hot.
I'll have to diagnose that. I might have screwed up some ignition wires trying to pull them out.
It's as if the throttle body is opening and closing fast.
Edit: I forgot to mention I have had gas cap open twice recently, so perhaps the purge valve is stuck open causing a vacuum leak.
Last edited by Agent-A01; Aug 29, 2019 at 08:11 PM.
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