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Somebody on the other forum states that it could still very well be that the oil cooler inside the valley of the V is leaking on the PCV system side, thus creating an vacuum leak.
I'll try to do another smoke test this weekend to confirm this issue (hopefully not)
I don't know about this oil cooler or PCV.... I like to base troubleshooting with evidence testing.
I can tell you this... I don't think your main issue is vaccum leak because your negative fuel trim at -22 says the opposite.
If you had a lean mixture with too much air (vacuum leak) the ECU would be adding gas, not taking it away, right?
timing chain
Observe the camshaft immediately near tensioner when you rotate the crankshaft 360° one way forward.
Normally camshaft should not be allowed to reverse using the slack from tired tensioner. You can fidle with this test or just replace tensioner.
Even the tensioner is not the primary concern... you got to get your trims under control to get a balanced engine. Don't cheat by enriching the lean numbers... work on spark and O2. You may have a leaky injector that's dropping uncontrolled fuel to computer is going against that. Use a bore scope...
Last edited by CaliBenzDriver; 09-06-2022 at 12:35 PM.
I've replaced all O2 sensors in the past few months, so I think we can mark those as good. I'll try to order the IC's for the coil pack this week, but components are either out of stock or very expensive.
I did some reading on fuel trims and misfires and it seems that if the oil is diluted enough (by gasoline) that misfires and very negative fuel trims could occur.
Oil change is happening this friday so we'll see.
Trying to understand the result of incorrect combustion here, wouldn't the unburned fuel cause the fuel trims to go up as there is too much oxygen in the exhaust gases?
I've replaced all O2 sensors in the past few months, so I think we can mark those as good. I'll try to order the IC's for the coil pack this week, but components are either out of stock or very expensive.
I did some reading on fuel trims and misfires and it seems that if the oil is diluted enough (by gasoline) that misfires and very negative fuel trims could occur.
Oil change is happening this friday so we'll see.
Trying to understand the result of incorrect combustion here, wouldn't the unburned fuel cause the fuel trims to go up as there is too much oxygen in the exhaust gases?
that is very good news.
O2 now trusted :
Now you're sure you and the ECU can trust these O2 combustion readings. These combustion results are what drives the ECU mixture calculations.
Troubleshooting steps:
It's not easy to troubleshoot systems with so many variables. Knowing what you trust and what you question is important. You cannot question too many things at once!!
If I were you, I'd question the ignition as a source of poor combustion, not the engine oil. Test the sparks with an inductive sensor so you can concentrate on bad cylinders.
LTFT:
Deeply negative LTFT is a sign the ECU is subtracting gas from mixture. You use this hard fact to then troubleshoot possible causes of too much unburned gas!
Practically: "Wouldn't the unburned fuel cause the fuel trims to go up... as there is too much oxygen in the exhaust gases?" - - > Unburned fuel cause ECU to lean out mixture by subtracting fuel with negative numbers.
Away from balanced condition:
The current fuel mixture is mapped with saved historical combustion data. When you replace essential parts (O2, fuel pump, coils, sparkplugs,...) you need to reset the ECU to have it relearn a more appropriate fuel map.
If not even with a 100% repaired engine using the old map, it will still run poorly.
Troubleshooting steps:
It's not easy to troubleshoot systems with so many variables. Knowing what you trust and what you question is important. You cannot question too many things at once!!
If I were you, I'd question the ignition as a source of poor combustion, not the engine oil. Test the sparks with an inductive sensor so you can concentrate on bad cylinders.
LTFT:
Deeply negative LTFT is a sign the ECU is subtracting gas from mixture. You use this hard fact to then troubleshoot possible causes of too much unburned gas!
Practically: "Wouldn't the unburned fuel cause the fuel trims to go up... as there is too much oxygen in the exhaust gases?" - - > Unburned fuel cause ECU to lean out mixture by subtracting fuel with negative numbers.
Away from balanced condition:
The current fuel mixture is mapped with saved historical combustion data. When you replace essential parts (O2, fuel pump, coils, sparkplugs,...) you need to reset the ECU to have it relearn a more appropriate fuel map.
If not even with a 100% repaired engine using the old map, it will still run poorly.
Understood, one theory against not going after the oil, there is quite a bit of Marvel Mystery Oil inside of my engine, which diluted the oil.
MMO is an octane booster and is rather flamable, so we could be having extra diluted engine oil, containing a flamable substance skipping by the oil control rings, or being sucked up through the PCV system.
I wouldn't place my bets on this either, but we'll see what happens once I change the oil this friday.
Originally Posted by CaliBenzDriver
that is very good news.
O2 now trusted :
Now you're sure you and the ECU can trust these O2 combustion readings. These combustion results are what drives the ECU mixture calculations.
Troubleshooting steps:
It's not easy to troubleshoot systems with so many variables. Knowing what you trust and what you question is important. You cannot question too many things at once!!
If I were you, I'd question the ignition as a source of poor combustion, not the engine oil. Test the sparks with an inductive sensor so you can concentrate on bad cylinders.
LTFT:
Deeply negative LTFT is a sign the ECU is subtracting gas from mixture. You use this hard fact to then troubleshoot possible causes of too much unburned gas!
Practically: "Wouldn't the unburned fuel cause the fuel trims to go up... as there is too much oxygen in the exhaust gases?" - - > Unburned fuel cause ECU to lean out mixture by subtracting fuel with negative numbers.
Away from balanced condition:
The current fuel mixture is mapped with saved historical combustion data. When you replace essential parts (O2, fuel pump, coils, sparkplugs,...) you need to reset the ECU to have it relearn a more appropriate fuel map.
If not even with a 100% repaired engine using the old map, it will still run poorly.
They are from a few weeks back, so they do not represent the current condition of everything (I cleaned sparkplugs afterwards), but close enough.
I think you are especially interested in the lambda control values, which tell how many fuel is injected based of the measurements of the O2 sensors.
Moreover, I got an camshaft position bank 1 sensor signal implausible DTC this morning, so I'm realy wondering if there isn't anything timing related going on here
Btw, if you'd like we can change to PM's to prevent any further hijacking of this thread. I'll make sure to share the conclusion afterwards
Understood, one theory against not going after the oil, there is quite a bit of Marvel Mystery Oil inside of my engine, which diluted the oil.
MMO is an octane booster and is rather flamable, so we could be having extra diluted engine oil, containing a flamable substance skipping by the oil control rings, or being sucked up through the PCV system.
I wouldn't place my bets on this either, but we'll see what happens once I change the oil this friday.
They are from a few weeks back, so they do not represent the current condition of everything (I cleaned sparkplugs afterwards), but close enough.
I think you are especially interested in the lambda control values, which tell how many fuel is injected based of the measurements of the O2 sensors.
Moreover, I got an camshaft position bank 1 sensor signal implausible DTC this morning, so I'm realy wondering if there isn't anything timing related going on here
Btw, if you'd like we can change to PM's to prevent any further hijacking of this thread. I'll make sure to share the conclusion afterwards
I don't know about Marvel snake oil... make sure it's not thining your oil viscosity (ie. pressure) too much and or known to spoil O2 sensors with contaminants.
Use a good oil that has good friction modifier package... Deutch Shell in the US sales Pennzoil "ultra Platinum" 0W40 that's nearly as good as the best Amsoil.
I don't know about Marvel snake oil... make sure it's not thining your oil viscosity (ie. pressure) too much and or known to spoil O2 sensors with contaminants.
Watch this... Best oil championship video test
Use a good oil that has good friction modifier package... Deutch Shell in the US sales Pennzoil "ultra Platinum" 0W40 that's nearly as good as the best Amsoil.
At this stage, I think it is thinning my oil viscosity, as that's what is made for. I've tried this in order to resolve possible clogging issues, which is seems like it has done.
I'll be putting in Castrol GTX UltraClean 10W40, which is a half synth.
Tim, I looked at the video of a your Xentry screens... did not come away thinking anything was bad and then wondered what I had missed ...
nothing odd not bad looking
When you "manually enrich mixture" and clean plugs: only you know the significance of what you're looking at. You know what cylinders you worked on.
small world!
Here is what I saw this evening on my way home a vroom licence frame ✌️
What did you think of the control values jumping around a little?
For reference, here are the codes from this morning.
The Secondary Air Injection codes are starting to annoy me too. The valve for the left bank is new, so the only possibility would either be a bad pump or clogged passages.
I wish people in the Netherlands would have such nice license plate holders, as they are all black 'n boring.
What did you think of the control values jumping around a little?
For reference, here are the codes from this morning.
The Secondary Air Injection codes are starting to annoy me too. The valve for the left bank is new, so the only possibility would either be a bad pump or clogged passages.
I wish people in the Netherlands would have such nice license plate holders, as they are all black 'n boring.
1 -- Camshaft pending code ...fix that!
This may not be an obvious fix. See if oil is present in connector. Swap sensor with identical from other bank. See if code follows sensor or stays.
This could be caused by wobbly tensioner!
2 -- I can't help with "Air Injection" faults
I am not familiar with how to test the failures of this Air system.
3 -- Your cat is hopefully not bad... 🤞
could be a lazy downstream (secondary) sensor partially plugged. Ignore for now, ok.
Last edited by CaliBenzDriver; 09-07-2022 at 03:45 AM.
1 -- Camshaft pending code ...fix that!
This may not be an obvious fix. See if oil is present in connector. Swap sensor with identical from other bank. See if code follows sensor or stays.
This could be caused by wobbly tensioner!
There was oil in the connector, in fact there is quite some oil in the harness 🙄
I've replaced that sensor last week and when starting cold, the first start goes bad (sounds like a tractor) and the second start immediately after is all well.
I need to take the intake manifold off in order to replace this sensor, which is absolutely horrible. Oh well, it does give me an opportunity to test the PCV side of the oil cooler for leaks.
Oh yeah, I'll also replace both connector's housings, as they are damaged and do not clip onto the sensor anymore.
Originally Posted by CaliBenzDriver
2 -- I can't help with "Air Injection" faults
I am not familiar with how to test the failures of this Air system.
This car throws codes when the vacuum system isn't able to actuate the valves, when diagnosing, I noticed that the valves stayed open whilst the pump had stopped.
I'm hoping that this is not caused by an vacuum leak or anything.
Originally Posted by CaliBenzDriver
3 -- Your cat is hopefully not bad... 🤞
could be a lazy downstream (secondary) sensor partially plugged. Ignore for now, ok.
Haven't replaced those sensors, this engine is known for eating cats and lambda's for a living, but I didn't replace them yet. The sensors looked quite old and original and I don't have the cat code all the time
Yesterday I tried to do the rotation test to see if the cams would roll back, using the starter motor. It all looked good, so there is no rollback. I do notice a slight rattle when the engine is running, that was only when cold, but it's here when the engine is warm too.
Changed the oil, resetted adaptations, engine feels much better.
I did an test of the PCV system, where I blew smoke into the vacuum line that connects to the throttlebody (the one that also connects to the purge valve) and no smoke came out of the system.
I've replaced all the connections between the PCV hoses and the hissing does sound a little different, so the hoses might have leaked a little too.
I've swapped the cam shaft sensors around and I still get the cam P0341 range/performance problem error code. I'm planning on replacing the connectors for those sensors since they are both not holding down on the camshaft position sensors housing.
Any ideas? I don't think it can be the wiring, since it'll fire right up when starting a second time
Oh yeah, when having the oil filler cap off when the engine is running, there are alot less vapors rushing out, which is a good sign!
Can't determine if the crankcase operates under a slight vacuum, but it's not pressurized as much as it was before the oil change.
The oil was still rather black and cloudy, the oil was in the engine for 5000kms. There where a few sludge pieces in the oil filter, so the MMO and Ultra Clean recipe worked out well.
Long Term Fuel trims are still negative (-5), but the engine has great power.
It's properly quick and was great fun on a parking lot with a bit of rain yesterday!
Tim these good results are positive steps in the right direction. Glad you're catching a break towards finish line
LTFT near -5 is closer to being even. You really want the trim to be positive because negative is leaning your engine which works against you during accelerations (spongee accelerator) !
++++ Camshaft DTC :
You've just saved yourself replacing 2x good sensors and some disappointement, that's nice !
- replace connectors
- chain tensioners
- Still replace sensors if they're leaking oil
Last edited by CaliBenzDriver; 09-10-2022 at 05:42 PM.
Tim these good results are positive steps in the right direction. Glad you're catching a break towards finish line
LTFT near -5 is closer to being even. You really want the trim to be positive because negative is leaning your engine which works against you during accelerations (spongee accelerator) !
++++ Camshaft DTC :
You've just saved yourself replacing 2x good sensors and some disappointement, that's nice !
- replace connectors
- chain tensioners
- Still replace sensors if they're leaking oil
Continuing the hijack for now ✌
Replaced the timing chain tensioner and when the engine starts properly; the engine runs better.
Less knocking when cold, but not completely gone.
What isn't gone is the P0341 code. I'm having more troubles with the camshaft sensor than before the replacement of the timing chain tensioner.
I'll try to replace the connectors this saturday. The trip to Germany is coming up very quickly so I need to have the car fixed before we go.
Just a theory;
Since the wiring loom connector of that sensor is badly damaged and I haven't had time to repair it, what are the odds that I've reversed the connections.
I'm guessing that when a hall effect sensor has a reverse polarity applied to it, output will become the logical not of the regular output.
So, the output will have an offset of half the square wave.
This means that the ECU was adjusting for this issue by changing the ignition point, which might explain the performance/range codes.
It could be that the ECU has given up on this and has let me down completely today.
Tim, you are right:
Nothing hooked up backwards tends to work well ... Your ability and determination to trace this problem down to that detail is brilliant !
The way so many parts are duplicated perhaps you can find an identical sensor on your engine -Or a picture of a spare part on the Internet.
WIS may help you with a pin-out information any clue is better than nothing to construct an educated guess.
Last edited by CaliBenzDriver; 09-28-2022 at 10:46 AM.
Tim, you are right:
Nothing hooked up backwards tends to work well ... Your ability and determination to trace this problem down to that detail is brilliant !
The way so many parts are duplicated perhaps you can find an identical sensor on your engine -Or a picture of a spare part on the Internet.
WIS may help you with a pin-out information any clue is better than nothing to construct an educated guess.
Thanks! This afternoon the car ran like vs until I fiddled with the wiring around the ground point that I removed to replace the chain tensioner.
I might want to start to take a look at all the ground point's connections.
I just replaced the connector housing and nothing changed.
Situation is even worse now, 2 seconds after the engine start, one bank stops working (randomized which one)
Checked the voltage transformer output and it's 179.9V for both banks.
I also got ESP, BAS and ABS error codes so I'm leaning towards electrical issues.
The half year old AGM showed 12.5V after a 40km drive which I found quite low.
Radiator needs to be replaced.
I don't think I'll be able to take the car on vacation on the 10th of October
Fixing broken connectors may not have solve your problem but now you are sure this will never become an additional problem 👍
12.5V unloaded voltage seems a bit low. Go ahead and read that thread on ALT Regulator, I go over the crazy regulation that can drain battery while driving, part time!
Fixing broken connectors may not have solve your problem but now you are sure this will never become an additional problem 👍
Exactly!
When comparing the old ones with the new ones, the old ones where quite broken and where missing 90% of the actual housing xD
Originally Posted by CaliBenzDriver
12.5V unloaded voltage seems a bit low. Go ahead and read that thread on ALT Regulator, I go over the crazy regulation that can drain battery while driving, part time!
My alternator is sealed and water cooled with an internal regulator
I do remember that at one point, I accidentally sparked the battery junction box underneath the passenger footwell. After that I replaced the battery as I've seen batteries die after a short circuit.
There are some electronics inside of that box, so maybe they got damaged.
On the other hand, if it was an alternator that failed, I'd have problems much earlier.
It could be possible that the battery was at it's floating voltage, since the battery voltage jumps to 14.4V with the car running.
I did notice that the camshaft position sensors positive wiring had a value of 2.0 ohms to ground, which is not good
Originally Posted by CaliBenzDriver
where are you going to vacation this time?
10th of october! So changing the radiator and fixing the electrical issues is going to be quite challenging
Tim: it's not because you see 14.4V right now that 30mn later the ALT is not going to put out a 12.1V drain on the battery.
I am not sure if your ECU is involved with controling your water cooled ALT. If it's independent it stands much greater chances to be reliable. But then why is battery low if it's charged as it should 😎
Unfortunately the ECU is in charge of the alternator output.
I'll perform the wiring check tomorrow as I've got the pinout of the ECU
Simply watch the battery voltage while driving. It has to always be 12.6V or greater.
If you see battery voltage below 12.6V, it means ALT is not carrying 100% of the load at all time as it should.
09-06-2022, 12:29 PM
