UPDATE: TGMO 5w20/Civic 96..thinning out..

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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!
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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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Good work mate, what is the listed / undiluted viscosity of TGMO ?

That GTX 5W20 has a KV100 of ~ 9 cSt, so if it's anything like that at the start, it has fallen a long way to ~ 7.5 cSt.

You did well tracking down and fixing the problem.
 
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You actually used a UOA as intended, that's quite rare around here, so I must congratulate you good sir!
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Great results. I was a mechanic at a Honda dealer before working my way on to UPS. Those engines are long lived. If by chance you have the very rare Civic HX, you have a gem. That was the best generation for the Civic as far as long term reliability is concerned.
 
Originally Posted By: SR5
Good work mate, what is the listed / undiluted viscosity of TGMO ?

That GTX 5W20 has a KV100 of ~ 9 cSt, so if it's anything like that at the start, it has fallen a long way to ~ 7.5 cSt.

You did well tracking down and fixing the problem.


Hey SR5! I don't know what the TGMO started at, but you're right if it was 9.0 it fell a lot in only a short time! Thanks! I'm really happy it's fixed. Kept wondering why everyone was always accelerating faster than me. lol.

Originally Posted By: OVERKILL
You actually used a UOA as intended, that's quite rare around here, so I must congratulate you good sir!
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Thank you!
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I know, imagine that, using an UOA as intended!!

Originally Posted By: skyactiv
Great results. I was a mechanic at a Honda dealer before working my way on to UPS. Those engines are long lived. If by chance you have the very rare Civic HX, you have a gem. That was the best generation for the Civic as far as long term reliability is concerned.


How'd were you able to guess what engine I have?! Awesome ability! Yes.. It is the rare HX, D16Y5 engine. The engine was rebuilt 13 years ago due to bad technicians damaging the crankshaft when they did the timing belt (crank pulley on crooked). But it was rebuilt with all honda parts, not cheap! It got passed down to me in the family, inherited really. Been fixing little things here and there, and just could NOT figure out what was wrong, then the UOA and bam! Now I have an answer. The injectors that were in there were re-manufactured, what a mistake that was. I bought standard motor products/intermotor NEW injectors since paying $200 for each injector from Honda is ridiculous! It's nice to finally get power out of the HX engine, still can't feel VTEC kick in though, it's more like a subtle tone change and then it begins pulling and pulling. I'm having fun again with this engine!

If you have any other tips about the HX, feel free to share!
 
Originally Posted By: andyd
I'm surprised you didn't smell the gas.


I have a really good nose too! I did sniff around and never smelled any gas, no leakage at any of the injector seals. I probably caught it early before it really started leaking more. What I could see was that the injectors would leak when pressure was applied to the fuel rail. I kept wondering why it would start on barely the first crank of the starter! Now, it's like 2 cranks and starts (normal).

The part that gave it away (besides the obd2 scanner live data) was listening to the injectors with a mechanics stethoscope. Could hear the bad injectors clicking but not a clean click, sounded like clicking under water. Then I knew fuel was just flowing by the internal o-ring seals.
 
Huge +1 to what OVERKILL stated so very well.

Researcher you have done some very good work on here lately. Keep on doing all that you have been doing. Absolutely great job with this UOA, and the VOAs.
 
Originally Posted By: andyd
I'm surprised you didn't smell the gas.


Me too. I'm also surprised the oil level wasn't rising a little.
 
Originally Posted By: bbhero
Huge +1 to what OVERKILL stated so very well.

Researcher you have done some very good work on here lately. Keep on doing all that you have been doing. Absolutely great job with this UOA, and the VOAs.


hey bbhero! Thanks for the comment, I appreciate it! I'll definitely keep up what I've been doing. I see you're using the Castrol Ultraclean 5w30, how's that working out for you? I felt that it might benefit others to do a VOA to know what was in the Castrol GTX and the GTX Ultraclean, since the info I did find was older, and formulas are always changing! Needed something recent to compare to.
I'm glad that everyone enjoys the VOA's and UOA's.
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Originally Posted By: bubbatime
Why the 5W20?


The story behind that was Honda back-spec'd 5w20 for the 96-2000 Civic 1.6L engine. I know that most can argue it was probably for CAFE credits but my thinking was different. When this engine was new it developed "piston-slap' not long into its life. It was only when the car was cold, once it warmed up no more noise. When the engine was rebuilt I wondered if maybe the piston slap developed because the oil was thicker when cold. Maybe that extra friction even if it was little would build up over time. Then the friction would wear away the rings a little to cause it to have more space. Then, piston slap until the rings expanded when warm. That was my theory.

Once the engine was rebuilt (not due to piston slap), I told the family member that had this car to try 5w20 only, see if the piston slap would be eliminated. Yes I know that it could've been a number of reasons piston slap developed but it was a gamble I was willing to take to save from an expensive rebuild, again. It's been using 5w20 since the rebuild many years ago. That's why the 5w20. And based on the UOA's, the wear isn't anything to be concerned about.

I have recently gone to the "thicker" GTX 5w20, which has a KV100 of around 9.0-9.1. Which is on the thicker side of the 5w20 spec. Kind of the best of both worlds, thicker 5w20, thinner 5w30 spec. So far it's working well, but time will tell.

Originally Posted By: demarpaint
Originally Posted By: andyd
I'm surprised you didn't smell the gas.


Me too. I'm also surprised the oil level wasn't rising a little.


That's the mystery, since after the previous oil change (before this current one) I noticed the oil was not registering properly on the dipstick. It could've been rising and I never would've known. Why? Because the dipstick was an aftermarket part. I got a Honda one and bam! The level was correct with how much oil the engine was filled with. So again, it could've been rising and it makes sense that it should with fuel diluting the oil, increasing the volume.
 
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