Currently driving an 03' G35 AT Sedan. When ever I break hard the oil light comes on and then turns off when I accelerate. I've also noticed a slight knocking noise during accelerating when the car switches from 3rd to 4th gear. I have a feeling that the noise is coming from the lifters not receiving enough oil due to an oil pump that is going bad and since the oil pump is going bad the oil light comes on when I brake. My check engine light also came on last night. I checked my gas cap and turn clicked it about 7 times so I know the check engine light didn't come on because of that.

Please let me know if any of what I'm saying makes sense. Any ideas would be greatly appreciated.

 

I would assume that you checked your oil level? You didnt mention it, so thought id check.

 

I checked the oil level today and I can't really get a good reading because when I pull the dipstick out its covered in oil. I wipe it clean and stick it back in and its still cover in oil when I pull it out. It was never like that before. My car has 91k miles

 

^Let the car sit for 30 minutes to an hour after driving then check the oil to get an accurate reading.

 

Change oil trust me same happened here

 

^Yep.

The VQ35 is really weird about not giving you an accurate reading unless it's been sitting for a while.
I've never had another car act like that

Make sure it's sitting on level ground, and give it a good hour without cranking just to be on the safe side.

 

Change the oil. Not something you want to mess around with. Measure how much oil comes out.

Also...get the cel code read.

 

Agree..


On a side note, check your oil once it's sat for a bit to get an accurate reading.

 

+9000 on VQ Dipstick suckage!

 

Yes, worst dipstick ever.

 

If you keep on breaking, you probably broke something...

 

I know that this is an old thread, however, I've Googled this for my specific vehicle, but this forum keeps coming up. So I figured it was time I contributed for a change.

I have an Infiniti M35x that was producing the same symptoms, oil light was coming on whenever I'd brake harder....and over a short period of time, the amount of braking required to light that indicator up became less and less. I knew I had a problem. So, I checked the oil, which as you may know, on an M35 is a royal pain in the ***! (I shamefully admit, it deters me from checking the oil levels as often as I should). It was extremely low.

But I was mystified as to why? I changed the oil every 10-12,000 km as specified and only used synthetic...the car has no leaks. Only one conclusion to draw...this old jalopy was burning oil.

So I took it in for service to investigate. They asked me how often I was changing the oil? I told them every 10-12k, no more ever than that. They informed me that as these engines age, the oil changes need to be more frequent and that I should be doing it every 5,000 km.

That didn't sound right to me. A synthetic oil change should get you to 12k without burning 2 litres of oil. But, that is the case. The engine has a clean bill of health otherwise...so I followed the advice and it's been fine at 5k intervals with minimal oil burn, if any, ever since. Something to try at least. Just change your oil more often.

 

A friend who's a diagnostic tech told me once that our check engine lights don't give complete information as to what's on with a engine nor do the rudimentary scanners a lot of us probably have. He said that there are a lot of underlying codes that will store in the computer and they will build up to the point that they trip the CEL. If I had one driving me nuts I'd probably hold my nose, get out my wallet, and have it scanned out and cleared.

 

@STaylor That sort of oil consumption is pretty normal to be honest. Just check it every week until you find out how often it needs to be topped off, you'll probably need to add oil every 2-3 weeks to top it off again. You do NOT need to shorten your oil change interval though, that guy just wants more of your money. 7500 miles / 12k kilometers on synthetic is completely fine but you have to keep the crankcase topped off so you aren't more than about 1/2 quart low (or 1/2 liter for you metric people).

@depmike38 That's not really how the DTC's work, there are codes that are monitored because they might have an infrequent miss in data, like when a cam sensor starts to go out. Usually it will fail slowly over a short amount of time like a few months. The ECM will store it as a "hidden code" meaning it's not a serious enough issue to start flashing the service engine light but it's something a mechanic will find when he plugs in an OBD2 scanner, they don't "build up over time" either, they just simply exist as a single value until they are cleared or the problem goes away and the ECM clears them. If it's a predetermined SERIOUS problem, like the sensor is sending NO DATA then the SES light will turn on because it's something that needs to be fixed right now. If a sensor is sending all of it's data but it's outside the expected range then that will also trigger the SES light. Some sensors will trigger the light no matter what the problem, if there is ANYTHING wrong with it then it lights up, throttle control motor and accelerator pedal switch are a good example of that.

It's really valuable for folks to own a cheapo OBD2 scanner just so you can plug it in every once in a while and make sure there are no hidden codes.

Also keep in mind that most scanners will only display ENGINE CODES, it takes a much more expensive scanner to be able to see SRS, transmission, ABS, and other non-engine codes.

 

i second this. i noticed my light flicker one day after a hard brake (amazing how we notice a little light turn on in the moment of nearly rear ending someone and ruining our cars) but thought nothing of it.

couple more times it came up and it concerned me, then within a couple days i could hear a knocking/rattle coming from the engine bay. but only heard it on one specific road in my neighborhood. the road was a slight incline. i did an uneducated guess and determined the oil level wasnt high enough, and because the incline it wasnt feeding the engine properly.

needed an oil change in a couple hundred miles anyways and changed the oil and filter. started her up and no noise, no light. drove it up that same road and still no noise. that was about 2.5k miles ago (now at 88k) and everything is still fine