Freelander Oil Catch Can

renald said:

Thanks one more time. Yes, to find the cause is being very hard. I hope you generate an idea. the trims are listed sequentially, but not for every time the SES lighted, as I did not wrote them all of the time, and in between there were different replacements and all the time the hope that the problem will be changed, but unfortunately it has not changed.

Click to expand...

Sorry i'v got another question. Are the trim fuel trim figures for the engine at idle or when driving? And over what time scale are we talking between readings.
The readings don't add up from what I can see. The ECU mixture is jumping between lean and rich then back to lean. This pretty much counts out an air leak or high fuel pressure. The only thing I can com up with as a fluctuating fuel pressure but that would have been picked up already.
Maybe the ECU has an adaptive fuel map error? Or the ECU is on it's way out.
Do you have access to T4?

That's OK. The fuel trim figures are when driving. The time scale for the measurements I wrote are from two years ago and recorded at irregular intervals, but I recorded the values when I took the reader with me, not always, and then I was upset with those errors and stop recording them. I just read the error an erase it. But I will start to record them again. The SES lights after running 6 to 8 miles. I do not have access to T4, I am using a MaxiScan OBD2 Reader. I can't answer on the adaptive fuel map error and ECU conditions, but I will do the best reading the RAVE for the adaptive fuel map error.

renald said:

That's OK. The fuel trim figures are when driving. The time scale for the measurements I wrote are from two years ago and recorded at irregular intervals, but I recorded the values when I took the reader with me, not always, and then I was upset with those errors and stop recording them. I just read the error an erase it. But I will start to record them again. The SES lights after running 6 to 8 miles. I do not have access to T4, I am using a MaxiScan OBD2 Reader. I can't answer on the adaptive fuel map error and ECU conditions, but I will do the best reading the RAVE for the adaptive fuel map error.

Click to expand...

I have a MaxiScan. I'll record mine for comparison's sake.
Will be interesting anyway!

If you were driving then the trims posted could well right. It's not uncommon to see fuel trims of + or - 15 or more while the car is in motion. I assumed the figures posted were done at idle which should be much more controlled.
However the ECU is still reporting mixture codes so something is amiss.
I can't think of anything that can cause this that you haven't already changed. Out of interest does you car have 1, 2 or 3 cat's and how many post cat sensors does it have?
You can't reset the adaptive fuel or ignition maps without T4.

Nodge68 said:

If you were driving then the trims posted could well right. It's not uncommon to see fuel trims of + or - 15 or more while the car is in motion. I assumed the figures posted were done at idle which should be much more controlled.
However the ECU is still reporting mixture codes so something is amiss.
I can't think of anything that can cause this that you haven't already changed. Out of interest does you car have 1, 2 or 3 cat's and how many post cat sensors does it have?
You can't reset the adaptive fuel or ignition maps without T4.

Click to expand...

My car has two cats and two post cat sensors, one per each cat. Unfortunatelly I can refer to the LR Dealer fon any thing else, the masters repeat that the car is not new, and if I do not see something wrong while in move, just go and don´t worry, blow-by gases and that´s all. I will install the oil catch tank and a new MAF (this time a genuine one) and see what the results are.

I take the decision to change the MAF sensor because las time when the mechanics get the car they cleared the Siemens MAF and after that I feel hesitation on the road.

renald said:

My car has two cats and two post cat sensors, one per each cat. Unfortunatelly I can refer to the LR Dealer fon any thing else, the masters repeat that the car is not new, and if I do not see something wrong while in move, just go and don´t worry, blow-by gases and that´s all. I will install the oil catch tank and a new MAF (this time a genuine one) and see what the results are.

Click to expand...

The car might not be new but it should tun well at 96K miles. Does it have 4 O2 sensors? 2 before the cats as well as the post cat sensors. Which sensors did you change?
If you have a non OE MAF then swapping that for an OE unit is a sensible idea.

Yes, it has 4 O2 sensors, as you said, 2 before the cats and 2 post cats. The changed sensor were the two before the cats, as they signal on lean or rich mixtures. The two sensors at the cats outputs are more for ecologic issues. Well, that was the explanation I received. Yes, the MAF is not OEM.

renald said:

Yes, it has 4 O2 sensors, as you said, 2 before the cats and 2 post cats. The changed sensor were the two before the cats, as they signal on lean or rich mixtures. The two sensors at the cats outputs are more for ecologic issues. Well, that was the explanation I received. Yes, the MAF is not OEM.

Click to expand...

Yes that's right. The pre-cat O2 sensors are what the ECU uses to monitor mixture for control. The 2 post-cat sensors are simply there to inform the driver that the engine is producing higher emissions than are permitted.
When did this fault start show it's self. Was it before or after the new MAF was fitted?

Mix too lean was all the time before replacing the "T" hose MLH500200, in which mechnics found a leakage, just after replacing it the car began to show the Mix to rich. The replacement of the MAF had no efect on car´s behaviour. Last time we had sometimes lean and sometimes rich mixes and know the car is showing just mix too lean, after cleaning the MAF and throttle body.

Maybe the ECU is still trying to compensate and just needs resetting.

renald said:

Mix too lean was all the time before replacing the "T" hose MLH500200, in which mechnics found a leakage, just after replacing it the car began to show the Mix to rich. The replacement of the MAF had no efect on car´s behaviour. Last time we had sometimes lean and sometimes rich mixes and know the car is showing just mix too lean, after cleaning the MAF and throttle body.

Click to expand...

Ok i'v a theory and Bukko has hit the nail on the head.
The pipe you had fail (MLH500200) is the air feed to the air assisted injectors. Under normal running conditions an amount of air passes into the engine via this pipe. The pipe MLH500200 takes it's air from the TB which is after the MAF. The ECU can measure the air mass and apply a standard fueling with minor correction using the O2 sensors for feedback.
However you had a pipe split. As i'v said this pipe feeds air to the injectors. It does this via drillings in the manifolds, this air then mixes with the fuel streams from the injectors and on into the engine. Because the air entering the pipe was unmetered and unmeasured, the ECU was unable to apply a standard fuel map because it was receiving conflicting mixture feedback from the O2 sensors. Over a period of time the ECU has learned to correct this error as it has been designed to do. You then fixed the pipe and the air leak stopped.
I'm assuming that the adaptive program data wasn't reset?. This has now confused the ECU because an adapted calibration it had set for this incorrect running condition which has now been resolved.
Then everything that you have changed since the pipe has been confusing the ECU more, this is because the ECU is adaptive on pretty much everything connected to it.
If the car was mine, first thing I'd do is find someone with T4 and clear down all adaptive maps. This will give the ECU a chance to relearn a correct adaptive correction.

Dear bukko and Nodge68,
Nice news for me, a new idea I will try to realise the soonest possible. And a very good explanation. Pardon for my late response, but I have been out. Be sure I will return with my feedback whatever the results. Thanks a lot.

The mechanics of the dealer replaced the timing belts yesterday and I asked them to clear the adaptive maps as only the dealer has a T4, I could not found other owners. They found that the big hose from MAF to the throttle body was cracked near the collar that fixes it to the throttle. They installed a bigger collar, said that there is not vacuum leak and suggest to replace this hose. I will run the car and see its behavior after clearing the adaptive values. I suppose it needs to pass some cycles before learning new adaptive values. I let you know.

Hi Guys,
I have a have good news, although I don't know how long it will last. After replacing the air flow duct PHD000120 and the MAF (both parts were replaced by new ones) the car is running without errors. The mechanics found some small cracks on the lower part of the duct, but the car still giving the lean error codes. They said that it could be the MAF and I bought a new one. After testing with the new MAF the master said that the codes appear on high revolutions, that they did all the tests on static mode, that they would like to test the fuel pressure with the car moving, but they did not have a suitable hose for that testing. I went home without any hope on resolving that problem, but after it we have run a lot of miles and all is OK. Thank God. I will try to install the oil tank on summer, but I am not sure where is the best place to cut the hose #3 on previous picture, on the part going after the T connection to the downstream of the throttle body (what is usually done) or before the T connection just before going down to the inlet manifold an further to the throttle body. Should you have any suggestions, please. Time is not an issue as I will do this work on spring or summer, too cold now for my hands.

renald said:

Hi Guys,
I have a have good news, although I don't know how long it will last. After replacing the air flow duct PHD000120 and the MAF (both parts were replaced by new ones) the car is running without errors. The mechanics found some small cracks on the lower part of the duct, but the car still giving the lean error codes. They said that it could be the MAF and I bought a new one. After testing with the new MAF the master said that the codes appear on high revolutions, that they did all the tests on static mode, that they would like to test the fuel pressure with the car moving, but they did not have a suitable hose for that testing. I went home without any hope on resolving that problem, but after it we have run a lot of miles and all is OK. Thank God. I will try to install the oil tank on summer, but I am not sure where is the best place to cut the hose #3 on previous picture, on the part going after the T connection to the downstream of the throttle body (what is usually done) or down the T connection to to the inlet manifold. Should you have any suggestions, please. Time is not an issue as I will do this work on spring or summer, too cold now for my hands.

Click to expand...

Thanks for the update!

Just curious, if all is good, why install a catch tank ?

May be you are right. I have been thinking on it.
But 3 years ago we had to purchase new VIS motors after getting relevant errors and one of them was really oily. I read this later: "Oil catch tank may help to prevent gumming up as a result of an oily residue deposited on the inside of the manifold as time and engine heat causes this residue to become a thick sticky muck. This muck helps increase resistance, binding and wear on the actuating rods and associated linkages. The increased load on the VIS motor can often result in their failure.The residue comes from two breathers connected downstream of the manifold and located either side of the throttle body".
But I have noted as well to much oil in the air flow duct (I know that some oil is normal there) and it seems to be that the MAF is usually dirty due to this oil. So that I am thinking to connect an oil catch tank and see what happens, I always can install new hoses and going back.

I bet now you have a new pipe on for the one that cracked you do not have the odour in the car do you ?

You know? I did not feel odour previously with the old duct in the car, I just found the oil while replacing the MAF or air filter, but not odour in the car.

Did you ever replace or clean with WD40 the oil vapor separator guaze in the cam cover ? They get full with age.

Part number LDM100080L. A couple of GBP each.

They are in my list of todos for the summer.