Instead of trying to post this update in the mess that became my last posting, I decided to post it here. Better visibility. It is also for those who may be new to the UOA world and trying to learn how to read an UOA lab report. Hopefully my experience can help others.
As some of you know, the viscosity of the TGMO 5w-20 oil in my Civic was thinning out quickly. I'm new to the whole UOA world and thought it was "normal" for oil to thin out over time, based on usage. That's not true at all, not at the rate I was thinning out! I began to get educated on what would thin oil out, fuel is the only thing that does that.
Yes, for some here it may be like you want to pat me on my head and say "awww he's learning" but it was a revelation to me!
I started to examine what in the engine could cause the oil to dilute with fuel and it was not a ring/compression issue. So..I pulled out the obd2 scanner and began to look at the STFT/LTFT (short/long term fuel trims, live data) and there I saw them running extremely rich! -25.7%!
Was able to diagnose the fuel injectors as being bad (independent of the scanner). Two of them were dumping fuel into the cylinders like a faucet! There's the fuel dilution. Replaced all four and now.. Power is back up, and fuel economy jumped 9mpg immediately! And yes I did change the oil when the injectors were changed.
I've read on here people complaining that the UOA's we get are "consumer-grade" but they are still more than capable of indicating that something is wrong in the engine. Yes blackstone missed the mark on my reports with fuel percentages, but looking at the viscosity and flashpoint told the story! I'm very thankful for the UOA reports, even if it's not perfect, because it caused me to realize something was wrong in the engine, I never would have thought to blame the injectors!
Attached is the UOA for the 96 Civic..
I have since switched over to Castrol GTX 5w20.. We'll see how that goes in the next analysis.
As some of you know, the viscosity of the TGMO 5w-20 oil in my Civic was thinning out quickly. I'm new to the whole UOA world and thought it was "normal" for oil to thin out over time, based on usage. That's not true at all, not at the rate I was thinning out! I began to get educated on what would thin oil out, fuel is the only thing that does that.
Yes, for some here it may be like you want to pat me on my head and say "awww he's learning" but it was a revelation to me!
I started to examine what in the engine could cause the oil to dilute with fuel and it was not a ring/compression issue. So..I pulled out the obd2 scanner and began to look at the STFT/LTFT (short/long term fuel trims, live data) and there I saw them running extremely rich! -25.7%!
Was able to diagnose the fuel injectors as being bad (independent of the scanner). Two of them were dumping fuel into the cylinders like a faucet! There's the fuel dilution. Replaced all four and now.. Power is back up, and fuel economy jumped 9mpg immediately! And yes I did change the oil when the injectors were changed.
I've read on here people complaining that the UOA's we get are "consumer-grade" but they are still more than capable of indicating that something is wrong in the engine. Yes blackstone missed the mark on my reports with fuel percentages, but looking at the viscosity and flashpoint told the story! I'm very thankful for the UOA reports, even if it's not perfect, because it caused me to realize something was wrong in the engine, I never would have thought to blame the injectors!
Attached is the UOA for the 96 Civic..
I have since switched over to Castrol GTX 5w20.. We'll see how that goes in the next analysis.
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