reset fuel trims; lasted about 60 miles or about an hour

[X5chemist]

As long as LTFT are close to engine size displacement, it's okay. Mine passed strict ODBII testing easily last week. Even with a $23 MAF.
What's oil weight?
Fresh fuel is always a plus. Even 10% ethanol absorbs water over time.
I'm taking the X5 for a near 80 mile round trip today. I'll monitor fuel trims.

[workingonit]

Originally Posted by X5chemist

As long as LTFT are close to engine size displacement, it's okay. Mine passed strict ODBII testing easily last week. Even with a $23 MAF.
What's oil weight?....

I'm impressed by the $23 MAF...I fully expected it to fail, since others expressed grave doubts concerning use of any non-OEM electronic part. So, far, I've replaced the MAF and exhaust cam position sensors with cheaper alternatives, and the both have worked fine. I don't know where the $23 MAF was manufactured, but the ecp sensor was made in Germany by a known good manufacturer, so I had confidence in it. If the MAF fails on the road, the X5 should at least limp home, but if the cam sensor fails, then I'm walking.

I wavered in my deciding between several types & weights of oil to use on the 211000 mile M54. Back in the old days, I'd change over to thicker oils on old engines, but we didn't have VVT (or Vanos) systems that like thinner oil. When "high mileage" oils came out, I used them on my old engines, to soften hardened/leaking seals mostly, and after many more miles, moved up to higher viscosity oils. I didn't worry about 40 weight oils even in winter (just a week or so around here), and even used 10W-50 in our old Oldsmobile Quad-4 engine (noisy timing chain liked it!).

My oil choices have been all synthetic since they first appeared, except for using Valvoline High-Mileage Blend, on one 350 engine that needed replacement anyhow. Never considered any conventional oil since I bought a '75 C-10 wher the previous owner had used only Pennzoil 30 weight conventional oil for 33 years, and when I removed the oil pan, it was caked solid with waxy oil sludge. I tried the Valvoline blend for awhile (maybe two months), but ended up rebuilding the 350 engine (became a good towing engine with 358 cubes, and a low-lift cam).

I have used Valvoline, Castrol, Mobile-1, Amazon Basics, and Royal Purple oil over the past 30+ years, and some Lucas oil products as additives, if needed. While in warranty, I used Mobil-1 in our GM vehicles (GM didn't accept Royal Purple, which I used in my race engines and performance-oriented daily driver engines, before gas prices rose in 2008), while I interchanged various high-mileage and higher-viscosity oils in between changes. Price wasn't much of a consideration, but I never considered house brand oil (or any Pennzoil), until I discovered Amazon Basics, which I now use on my other cars & trucks (not the X5). I researched Amazon Basics, and found it was highly regarded, so why not? It's been my go-to oil now, in both 5W-30 and 5W-30 High-Mileage.

While wavering between brands, I also dithered in choosing grades 5W-30 vs 5W-40, regular or high-mileage, and should I try out a new to-me brand, Liqui Moly. I watched many videos, read many posts on many forums, and decided that I liked the European specs and LL-01 certs that Liqui Moly had, but since my X5 had come originally with Castrol, I found their Euro-spec 5W-40 at Walmart in 5 quarts and singles, for the same as Mobile-1, and decided on using it again; I couldn't find other (than Liqui Moly) oil with similar certs and specs (I tried for three months) by brands I knew and trusted, so I bought the Castrol. Cheaper than LM also. We'll see if the thicker oil will negatively affect the re-built Vanos, but other than that consideration, I'm happy with Castrol.

[X5chemist]

Foxwell data for ~80 mile round trip.
Pic#1 - Cold start and idle for a few minutes. Temp 115F
Pic#2 - Temp @173 running 70 MPH
Pic#3 - Temp @180 running 70 MPH
Pic#4 - Temp @183 running 70 MPH
Pic#5 - Temp @183 MAF 0.04 lbs/s

I'm actually surprised. The new thermostat runs cooler than I thought. It was a cool morning. Plus the mechanical fan clutch is new. 193F was the highest temp I saw. Adding and subtracting STFT and LTFT = ~0! STFT did go up and down on hills vs straight road.

[workingonit]

Fuel trims looking good, and pretty consistent. Mine seem consistent, but not as good. Whereas your LTFTs are negative (-3.9 to -4.7, mostly), mine are positive (+9.xx to +10.xx, but tapering down lately to +3xx to +4.xx, on my last trip). My STFTs are trying to balance them out, and read correspondingly negative.

I haven't zeroed my fuel trims (either by unplugging the MAF, which always works, or by resetting adaptations with the Foxwell...which doesn't work everytime) since I first installed the $23 MAF. Have you, in order to get a low LTFT baseline? It's been months since I saw zero LTFTs.

But, perhaps it's the difference in our driving habits/routes/speeds causing the differences? I hardly ever get to 70 mph, as I rarely hit a highway, but just go stoplight-to-stoplight at 40 mph. My Electric fan maintains 194 F or below, in all conditions (with original 90C thermostat and 2.0 bar coolant cap), so that might also contribute to a difference.

I'm also totally unsure that I haven't got a microscopic, un-findable vacuum leak, still persisting even after all the months of testing I did. Perhaps the miracle-cure the $23 MAF performed isn't a case in total remission. Unless I can get better performance data (more like yours, at higher speeds), and/or get another (tested as good) probably OEM MAF to compare data with, I might never know for sure. So, I'll keep watching my data, and learn to be happy (so far) with the good results (passed inspection!!!).

[X5chemist]

No, I've never unplugged the MAF to zero fuel trims. The 100 mile run that day changed engine performance. Driving in town now, it runs smoother. Seems, keeping it at high RPMs for a good run helps. I'm now topping it off with Castrol 5-40W A3/B4. Oil changes have been with Castrol 5-30W A3/B4. The filter was changed at half oil life to continue cleaning up the engine inside. Windage tray and oil pan had so much gunk built up. The Mahle thermostat runs cooler than expected. Mine does have a lower bar tank cap.

[workingonit]

Originally Posted by X5chemist

... The 100 mile run that day changed engine performance. Driving in town now, it runs smoother. Seems, keeping it at high RPMs for a good run helps....

I'm sure I've mentioned this before, but I've not been able to drive my X5 at or over 70 mph for more than 10 miles at a time, before entering stop & go traffic conditions...not conducive for the old Italian tune-up (or as I used to tell my mother: "I need to take your car tonight, and blow out the carbon build-up").

I wasn't really kidding my mother, she'd never get her '68 Pontiac Bonneville over 45 mph, for months at a time, and the 400-4 barrel engine would suffer for it; the 383 Magnum-4 barrel engine in my '67 Dodge Monaco 500 never had that problem...it was like night and day difference after I'd drive it for awhile. I'm sure my X5 needs the same treatment.

Your Castro 5W-40 must be the same version I used

with the same A3/B4 specs (among others). Since mine is older, with higher mileage, the LL01 is important, as is the 40 weight, due to Texas ambient heat, I would expect. However, when I started the engine after the fill, the Vanos made a noise I'd never heard from them before...I hope that they can accommodate thicker viscosity oil (my '09 HHR with VVT didn't like it, so I went back to 30 weight).

[wpoll]

Originally Posted by workingonit

However, when I started the engine after the fill, the Vanos made a noise I'd never heard from them before...I hope that they can accommodate thicker viscosity oil (my '09 HHR with VVT didn't like it, so I went back to 30 weight).

In (simplistic) theory, the 5W-40 is not any thicker than the 5W-30 - at start-up when the engine is cold (the 5W part).

In practice, it is a little thicker (kv @40C is 84 vs 70) but still thinner @40C than the 5W-30 would be at say 10C.

It's likely the various noises you heard would be due to the engine being drained of oil and the slow re-fill time as the oil pressure comes up after the drain. Esp. so if the drain was more than 20-30mins (something it try to avoid doing).

I too run the "thicker" 5W-40 Castrol Edge, due to the aging engine components (turbo bearings!) and have done so since 200,000kms (70,000kms ago) but I figure it's probably more "placebo" than engineering/science.

[workingonit]

Originally Posted by wpoll

...It's likely the various noises you heard would be due to the engine being drained of oil and the slow re-fill time as the oil pressure comes up after the drain. Esp. so if the drain was more than 20-30mins (something it try to avoid doing)....

That's probably what happened; my oil change took 3.5 hours (including clean-up), and the oil wasn't refilled until the 3-hour mark...much, much longer than it should've taken. I even put the filter in dry, so the pump had to saturate that before the lifters & Vanos got any oil. Not going to use the extractor pump again, too slow, but just drain the oil using a larger drain pan, so I can refill before the delicate parts go dry.

But, in my experience using good synthetic oil, there should be a film of oil retained inside, so that no metal actually went dry. I've had race cars sitting all winter, and our spare vehicles sitting several months between starts, with no damage to bearing surfaces, lifters, and bores due to lack of oil film (confirmed by tearing down several race engines over the years). I'll always use good synthetics for that reason.

[workingonit]

Originally Posted by workingonit

Fuel trims looking good, and pretty consistent. Mine seem consistent, but not as good. Whereas your LTFTs are negative (-3.9 to -4.7, mostly), mine are positive (+9.xx to +10.xx, but tapering down lately to +3xx to +4.xx, on my last trip). My STFTs are trying to balance them out, and read correspondingly negative.

I haven't zeroed my fuel trims (either by unplugging the MAF, which always works, or by resetting adaptations with the Foxwell...which doesn't work everytime) since I first installed the $23 MAF. Have you, in order to get a low LTFT baseline? It's been months since I saw zero LTFTs.

But, perhaps it's the difference in our driving habits/routes/speeds causing the differences? I hardly ever get to 70 mph, as I rarely hit a highway, but just go stoplight-to-stoplight at 40 mph....

Originally Posted by X5chemist

No, I've never unplugged the MAF to zero fuel trims. The 100 mile run that day changed engine performance. Driving in town now, it runs smoother. Seems, keeping it at high RPMs for a good run helps.

Finally got in a 100 mile trip,
https://xoutpost.com/1225900-post916.html though in heavy rain, with 50% of it at 50 mph and below (I tried to compensate by exceeding posted and sane...considering the weather...speed limits). Not a confession, as I was driving in "Mexico"....

The higher speeds, and up & down hills as well, seemed to increase throttle response, brought my avg.mpg reading up to 15.5-15.7 from 13.8-14.0 last week, and I watched the fuel trims get better as I drove.


Perhaps, someday, they'll get steadier, nearer to zero (though I suspect 2 injectors need adjustment, from readings I got using Bimmer Tool last week). Perhaps my Foxwell can help me there?

I have temporarily settled on using my 8" tablet as my data display from now on, moving the tablet to a CD slot mount from a wobbly post I had it on. The tablet is bigger in size, better in legibility, and remains connected better than the old cellphone I was using before. Torque Pro as data display, Google offline maps, and nothing else on it to interrupt the data. I'll use my Foxwell to get deeper data when needed, and fix what's wrong, until I can get Android+I-bus and a laptop with INPA/ISTA.

[X5chemist]

Does any manufacture make a four hole fuel compatible fuel injector?