Below is a UOA of my wife's Malibu. Most of the miles were accumulated during the winter months 50-50 hiway and city. I did use a bottle of Gumout all in one after I read this report.
16 Malibu, 1.5 liter, HPL PCMO 5W30 5,400 miles
- Thread starter BobsArmory
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4WD
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What was the oil in the other columns?
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@BobsArmory - I'm familiar with this engine. You may have a mild case of fuel dilution from caked on injectors. Go online ('cause it's cheaper) and get yourself some Red Line SI-1 (at least 4 bottles) and run two bottles with the first fill-up and then one with each subsequent fill-up in your gas tank. Alternatively, go to Napa and get at least a couple if quart bottles of Techron Concentrate and run one bottle per fill-up. It should clean whatever dirt you have on the injector nozzles. At that mileage you could have at least one leaky injector, but I'd recommend you try the cheaper route first with injector cleaner.
Does your wife tend to do extended warmup of the vehicle in the winter? 5-10 mins? This is an early implementation Di turbo?
I also see the high fuel % in the previous Fall Season sample in 2021- so could be a bad spray pattern on one or more injectors.
If the Fuel Dilution were not an issue on this run, this HPL Oil could have gone 10,000 miles or maybe 12,000 miles.
If reports still evidence 2x iron after a rinse and repeat - It could point fuel wash or to a DP/EP imbalance. The Mg compound is 3x typical treatrate. Fuel dilution needs to be addressed
What is DP/EP imbalance?
Further testing to narrow down where or what is causing, to see the trend upon future samples, could shed some more light on what is causing the added wear. We can speculate that it's the fuel but the previous sample didn't have the same effect on Fe. Interesting to speculate though & I'm not sure what HPL says about how far their oils can go or do they just rely on UOA testing?
Think they're talking about Detergent package (additive pack) treat rates/ratios might be off.
Basically, in this UOA sample there could be a bit of oil leftover from his previous OCI. So, we may need at least 2 runs of the HPL Oil with UOA's of the next 2 runs of HPL.
JTK
$100 Site Donor 2025
Do we have anyone on BITOG running HPL on a GDI engine for 10K miles+
No it's a fairly modern DI system, with centrally placed injectors which improves cylinder wall wetting but can lead to more coking of injector tips.
If you have a code reader that can read live data, you can diagnose leaky injectors easily: start the engine and run for 20 ish seconds, then turn off and read the rail pressure: the rail pressure should stay the same or rise (from heat reaching the injectors), but if it drops steadily you got a leak.
Triple_Se7en
$50 Site Donor 2024
Bob
Friend just bought one of these with the 1.5.
Curious what primary gasoline brand you buy and what octane level?
Also, is this HPL analysis the PCEO? There are at least three different ones listed as being PCMO.
Friend just bought one of these with the 1.5.
Curious what primary gasoline brand you buy and what octane level?
Also, is this HPL analysis the PCEO? There are at least three different ones listed as being PCMO.
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Regular 87 octane. I would say 70% Meijer gas (top tier) and 30% Murphy (not top tier)
Yep she tends to remote start in the winter months and let it warm up for a few minutes
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