Rear Timing Gasket failure causes low oil pressure: no SES
First off, I had a leaking gasket on my car that, in spite of measuring a mere 5psi at idle, never threw a CEL. Even if there is not enough oil pressure to meet the minimum operating spec of 14psi at idle, if there is still just a few psi left, the light will NOT go on. The low oil pressure sensor is really just a switch that only goes off when there is basically NONE; a very poor design!
Next, the belt most definitely needs to come off to perform the rear timing cover gasket repair (crap, the whole front of the engine comes off!). They are correct that there is nothing to tighten, as the belt has a spring loaded auto-tensioner (like pretty much ever car made nowadays). I would guess the issues with the belt squeak may have to do with the tech inadvertently getting some oil or grease on one of the pulleys or the belt during reassembly. It may yet wear off after a while, so I wouldn't necessarily get too worried about it (unless it's really screaming).
All in all, consider yourself lucky that you got this one covered. It's a ridiculously expensive repair that unfortunately will be borne by many owners in the future, AFTER they are out of warranty (i.e. you dodged a bullet on this one!).
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Next, the belt most definitely needs to come off to perform the rear timing cover gasket repair (crap, the whole front of the engine comes off!). They are correct that there is nothing to tighten, as the belt has a spring loaded auto-tensioner (like pretty much ever car made nowadays). I would guess the issues with the belt squeak may have to do with the tech inadvertently getting some oil or grease on one of the pulleys or the belt during reassembly. It may yet wear off after a while, so I wouldn't necessarily get too worried about it (unless it's really screaming).
All in all, consider yourself lucky that you got this one covered. It's a ridiculously expensive repair that unfortunately will be borne by many owners in the future, AFTER they are out of warranty (i.e. you dodged a bullet on this one!).
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Thanks for the solid answer. The belt's been squeaking for nearly two weeks now, so I don't know if any accidental grease on the belt would have worn off by now. I'm still think it has to be something the shop did when they put the belt back on as it never squeaked before the repair. It'd be too much of a coincidence to have the belt suddenly start squeaking due to being old the day after they removed and reinstall the belt.
To answer a few of the previous questions:
The repair was covered by the powertrain warranty.
Given that this is an 18 hour $3500 job, it may not be crazy to get an oil pressure test done before your warranty runs out? The service advisor told me that there is a TSB out for the problem, so you might bring that up to the the shop in order to encourage them to check the pressure for without charge since you don't have any symptoms. As mentioned earlier, I had zero indication anything was going wrong with the oil pressure; I got lucky they found it when looking for another problem.
My car was build on 12/10. The dealer did confirm that Infiniti fixed the gasket on future models, but didn't say what years no longer have the weak gasket.
I recall BB saying this issue happened on his wife's car, so I'm not sure if that means anything about how driving style affects the gasket going out. I drive my car hard, but that may have nothing to do with it.
The repair was covered by the powertrain warranty.
Given that this is an 18 hour $3500 job, it may not be crazy to get an oil pressure test done before your warranty runs out? The service advisor told me that there is a TSB out for the problem, so you might bring that up to the the shop in order to encourage them to check the pressure for without charge since you don't have any symptoms. As mentioned earlier, I had zero indication anything was going wrong with the oil pressure; I got lucky they found it when looking for another problem.
My car was build on 12/10. The dealer did confirm that Infiniti fixed the gasket on future models, but didn't say what years no longer have the weak gasket.
I recall BB saying this issue happened on his wife's car, so I'm not sure if that means anything about how driving style affects the gasket going out. I drive my car hard, but that may have nothing to do with it.
Last edited by Ryne; Mar 4, 2015 at 10:30 PM.
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Crap! Same build date as mine, and my odometer is only at 22,000 miles with about 27 months left on the powertrain warranty. Ironically, my decision to go with a G37 vs my second choice 328i was the BMW vanos issues. Looks like I chose poorly.
But following VQs regimen of oil pressure data surely is a good plan
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From: Bay Area, CA
Whats up guys. I know this is bringing up an old thread, but I think I am having this problem. Same exact problem as OP, car sometimes doesnt start on warm starts, not cold or hot. got TB cleaned with my 60k miles and infiniti said nothing was wrong. So the TB fixed it for maybe 3 days. Replaced battery and left it as since. Ever since, its been happpening every now and then.
I also feel like I'm getting very little power on the low end side and I sometimes get jerks when downshifting when breaking lightly? Its weird. I still have powertrain warranty. How should I approach the situation? I would not like to cash out $3500 since I just spent $$ on a CBE, but I would like to keep my G. I also have no code. Thanks!
I also feel like I'm getting very little power on the low end side and I sometimes get jerks when downshifting when breaking lightly? Its weird. I still have powertrain warranty. How should I approach the situation? I would not like to cash out $3500 since I just spent $$ on a CBE, but I would like to keep my G. I also have no code. Thanks!
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From: Bay Area, CA
1) 60k Maint at Infinity
2) Cleaned TB at Infinity
3) Replaced Oil (less than 600 miles)
4) Replaced Battery (less than 1000 miles)
But yes, I have gotten no low oil pressure lights or anything. They said if it is the gaskets, they will replace it under powertrain warranty.
To get them to check oil pressure, you will have to tell them to check the oil pressure. It's not a part of any regular service or usual diagnostic unless you request it. Have them check it at idle and under load and tell you exactly what it is. The oil light won't come on when it's low, only when it's nonexistent. Mine was around 5 PSI with no light.
Also have them check for vacuum leaks and that it's getting enough fuel.
Also have them check for vacuum leaks and that it's getting enough fuel.
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From: Houston, TX
So what happen if you have an oil pressure gauge & noticed low oil pressure or lowering oil pressure.. Will this help you fix the issue sooner or cheaper?? Cause if it shows low or lower,, isn't basically telling you the gasket is leaking and/or is bad??
In the end, you will replace the gasket which is costly.. Or is there something that can be done/repair with low oil pressure warning from gauge??
In the end, you will replace the gasket which is costly.. Or is there something that can be done/repair with low oil pressure warning from gauge??
So what happen if you have an oil pressure gauge & noticed low oil pressure or lowering oil pressure.. Will this help you fix the issue sooner or cheaper?? Cause if it shows low or lower,, isn't basically telling you the gasket is leaking and/or is bad??
In the end, you will replace the gasket which is costly.. Or is there something that can be done/repair with low oil pressure warning from gauge??
In the end, you will replace the gasket which is costly.. Or is there something that can be done/repair with low oil pressure warning from gauge??
I am still a little confused on the lights:
Oil pressure dummy light: So we know that this light will not turn on until basically there's ZERO oil pressure
CEL: When does this light turn on due to low oil pressure? Almost zero?? Below 5psi?
Oil pressure dummy light: So we know that this light will not turn on until basically there's ZERO oil pressure
CEL: When does this light turn on due to low oil pressure? Almost zero?? Below 5psi?
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Same here, I got a CEL and the same codes, but I never checked the oil pressure, there was no doubt that it was the timing cover gaskets so I just tore into it since I was out of warranty. BOTH of my gaskets were blown so the symptoms were much more evident than yours yet no oil pressure light at all. After researching, these gaskets can fail with or without a CEL and/or oil pressure light so definitely get your oil pressure checked, it's the one failsafe way to test those damned gaskets and if you're under warranty then get it done. This really does get pricey out of warranty, gl
Er-r-r... scary thread. 
So yesterday I had the car in for inspection, and discussed this point-of-failure with the Infiniti dealership's Senior Tech. He confirmed that this is an issue with the G37 from '09 through '11. And he confirmed that it's covered under the Powertrain Warranty. However, he also said they've had maybe 6 such repairs in all the years that he's been with Infiniti.
So it's a real thing, no doubt. But I'm feeling more comfortable knowing about this, and reassured that it's a low-yield problem.
Oh, and he also confirmed the expense... the entire front of the engine gets tore down, and this takes a couple of days. Yikes!
So yesterday I had the car in for inspection, and discussed this point-of-failure with the Infiniti dealership's Senior Tech. He confirmed that this is an issue with the G37 from '09 through '11. And he confirmed that it's covered under the Powertrain Warranty. However, he also said they've had maybe 6 such repairs in all the years that he's been with Infiniti.
So it's a real thing, no doubt. But I'm feeling more comfortable knowing about this, and reassured that it's a low-yield problem.
Oh, and he also confirmed the expense... the entire front of the engine gets tore down, and this takes a couple of days. Yikes!