Chasing Mercedes E350 Misfire




but the other way around...
timing issues do cause misfires, guaranteed they can.
here both intakes are shifted
for only one misfire...
Is that with engine running now???
Last edited by CaliBenzDriver; Oct 24, 2024 at 01:42 PM.




"$10K-Oil-in-Harness!"
Go check CPS + ECU for oil swamp
What caused the misfire after Gym...
is oil soaking into lambda!!
Time for spray cleaning + CPS + pigtails + Lambda
There you have it.

Last edited by CaliBenzDriver; Oct 24, 2024 at 01:26 PM.

Oh you’re saying I need a new CPS and lambda? I’ll check for any oil.
Last edited by Tdavid1; Oct 24, 2024 at 01:26 PM.




So far this bargain is a keeper.
parts
Last edited by CaliBenzDriver; Oct 24, 2024 at 01:29 PM.




I hope for your sake (and your wallet) it is a simpler fix.
Folks, does this model also have the timing chain stretch issue in certain years?
The Best of Mercedes & AMG




The VVT No1 job is to compensate exact cam position for chain wear... when given enough oil pressure.

Last edited by CaliBenzDriver; Oct 24, 2024 at 01:48 PM.




Extreme No say intake VVT Gears are not locked.
check cam sensors at least the one easily accessible from Bank1 intake:
oil galore in sensor?
Without ratlling and extreme position + extreme Lambda is textbook... "oil in harness".
Last edited by CaliBenzDriver; Oct 24, 2024 at 01:55 PM.




There is also the scientific approach with a pico-scope.




This is a sofisticated Mercedes....
-- It can runs both good and bad.
- good enough to go earn keep
- bad enough to hand over bundles at MB specialist
VVT rattle when unlocked but then get in position given pressure.
In fact we can have you do a little free experiment to save $1k with zero parts.
Run solenoid MOD-3 with good oil + good pressure.
This should provide much needed pressure to prevent timing code.
The poor oil pressure is what's wasting the VVT lock pin... cleaver Mercedes!
Thats why you want free MOD-4.
Last edited by CaliBenzDriver; Oct 24, 2024 at 02:07 PM.




then you are overqualified.
These cars are extremely well built to be serviced.
you won't need to drop V6 engine.
Here its NOT whole timing cover out.
If you want new VVT Gears...
it's injectors/HPFP/Valve cover out and
then again you can bump up oil pressure to normal levels.
Will cost you zero and save time.
+++ the only thing is... beware of aluminum bolts
MB likes the "one-time use" fasteners torqued to yield...
aluminum is 2-fingers tight.

+++ PCV Included
when removing HPFP...
Do the PCV with plastic breather line.
+++ Vacuum pump chevk-valve...
on the rear of bank2 exhaust cam you will find vacuum pump with a bad $5 check valve awaiting for your attention.
Last edited by CaliBenzDriver; Oct 24, 2024 at 02:35 PM.




However, you can first try @CaliBenzDriver 's suggestion of disconnecting the oil pump solenoid for a few hours, delete codes, rescan, and see how it changes. Just be careful you may get addicted and not be willing to put it back
. You then decide if you want to dive deeper into other details.




However, you can first try @CaliBenzDriver 's suggestion of disconnecting the oil pump solenoid for a few hours, delete codes, rescan, and see how it changes. Just be careful you may get addicted and not be willing to put it back
. You then decide if you want to dive deeper into other details.MOD-1 definitely but above thin stock...
Thin stock is what causes low pressure to wear VVT pin.
Start with JC's excellent Motul 5w40 (it's far better than thin stock oil sheared as 10w30).
I can't recommend him to skip to 5w50 on 100kMi engine rings though that's what's needed to position VVT at idle without any VVT replaced.
Last edited by CaliBenzDriver; Oct 24, 2024 at 02:45 PM.
then you are overqualified.
These cars are extremely well built to be serviced.
you won't need to drop V6 engine.
Here its NOT whole timing cover out.
If you want new VVT Gears...
it's injectors/HPFP/Valve cover out and
then again you can bump up oil pressure to normal levels.
Will cost you zero and save time.
MB likes the "one-time use" fasteners torqued to yield...
aluminum is 2-fingers tight.

+++ PCV Included
when removing HPFP...
Do the PCV with plastic breather line.
+++ Vacuum pump chevk-valve...
on the rear of bank2 exhaust cam you will find vacuum pump with a bad $5 check valve awaiting for your attention.
So the whole timing cover doesn’t come off? So I’ll be removing valve covers and mainly changing the cam adjusters along with the small things while I’m in there? How many adjusters do I replace and how can I tell which one is bad? They’re pretty expensive..
im confused.. what would cost me zero and save me time?
Last edited by Tdavid1; Oct 24, 2024 at 02:45 PM.




MB likes the "one-time use" fasteners torqued to yield...
aluminum is 2-fingers tight.

+++ PCV Included
when removing HPFP...
Do the PCV with plastic breather line.
+++ Vacuum pump chevk-valve...
on the rear of bank2 exhaust cam you will find vacuum pump with a bad $5 check valve awaiting for your attention.
So the whole timing cover doesn’t come off? So I’ll be removing valve covers and mainly changing the cam adjusters along with the small things while I’m in there?
How many adjusters do I replace and how can I tell which one is bad?
They’re pretty expensive..
im confused.. what would cost me zero and save me time?
DE cars eat parts!
US cars drink gas!
JP cars drive Miles !
All based on Bosch engineering goodness.

+++ Still not checked yet ...
before rushing into Intake VVT job...
Check that VVT gears pins are unlocked
or CPS are telling jokes to ECU.
or both VVT+ CPS.
We are trying to minimize your efforts not inflate the tab.

Last edited by CaliBenzDriver; Oct 24, 2024 at 02:56 PM.
DE cars eat parts!
US cars drink gas!
JP cars drive Miles !
All based on Bosch engineering goodness.

+++ Still not checked yet ...
before rushing into Intake VVT job...
Check that VVT gears pins are unlocked
or CPS are telling jokes to ECU.
or both VVT+ CPS.
We are trying to minimize your efforts not inflate the tab.

How many adjusters do I replace and how can I tell which one is bad?
They’re pretty expensive..
im confused.. what would cost me zero and save me time?
How do I check the VVT gear pins?
Last edited by Tdavid1; Oct 24, 2024 at 03:01 PM.




The M274/6/8 engines use a clever pump solenoid to disable half the oil pressure below 3500.Rpm
When you unplug pump solenoid, engine is allowed to run on normal oil pressure that can then be increased by way of viscosity to offset the "under rev'ed" pump.
Here MB uses a low Max pressure of 60psi while GM uses 90Psi. The oil pump has lazy output to "save gas".
You can turn that around with better viscosity in the W50 range.
Beware your 100kMi piston rings are jammed with soft carbon from gallons of burned oil deposits.
Feeding 10W50 directly without any cleaning steps *may* help cause LSPI self-ignition piston damage.
Normal oil pressure remains a valid experimental option with working VVT a lot of us are using. You don't need bad VVT... in fact good VVT's benefit from not overworking lock pins with reduced oiling.
Last edited by CaliBenzDriver; Oct 24, 2024 at 03:23 PM.
This M276/8 uses a clever pump solenoid to disable half the oil pressure below 3500Rpm
When you unplug sokenoid engine is allowed to run on normal oil pressure ypu can then increase with viscosity to offset the under reved pump.
Here MB uses lower Max pressure of 60psi while GM uses 90Psi. The oil oump has lazy output.
You can turn that around with better viscosity in the W50 grades.
Beware your 100kMi piston rings are jammed with soft carbon from burned oil deposits.
Feeding 10W50 directly without any cleaning steps *may* help cause LSPI self-ignition piston damage.
If you manually rotate engine by crankshaft, you will hear/see a click and a jump if the VVT gear is faulty. You will know it when you see it, and there are videos online too






