Took 03 G35 Sedan in today because the oil pressure light was coming on when warm/low idling. Shop said that I have about 5 PSI lost when idling. They said I need to replace the oil pump which will cost around $1500. Does this sound right? Does the price sound right? I could have my brother pull the engine and rebuild it for less. The mechanic told me that there is timing things that most mechanics would not be able to do if they replaced the oil pump.

Thanks for you help. This has be totally bummed out since it's my baby and only has 116k on it.

 

We have yet to see a VQ oil pump fail, most likely you have excessive wear in the bearings causing low oil pressure. Your mechanic is right it is a very labor intensive job, the part is less than $200. Not all mechanics are competent enough to properly reinstall the timing parts. We have had cars come through our shop with 300k+ miles with original oil pump, your lack of oil pressure is a symptom of a real problem. And as far as installing new bearings, the labor is nearly the same as just changing the oil pump.

Let me know if I can help you with anything.
-Rob

 

Rob,

My brother in law is a mechanic. Is there a DYI he could look at determine if the timing parts would be too complicated for him to perform the work? Reading your post it sounds like if replacing the pump should also perform bearing replacement?

 

Rob is basically talking about rebuilding the engine. all new machine work, all new bearings. total engine teardown.

 

I know brother in law could do a rebuild for $500 or less, but what are the difficult timing stuff everyone keeps talking about

 

Also is this a must be done now or can it wait? As you can tell I'm not a mechanic, but I can do anything with computers lol

 

I think Rob is right. The problem most likely has nothing to do with the pump. It's a terribly simple device.

You're brother might be a great mechanic, but it would be far easier just to find a junkyard motor and swap it in rather than rebuild. It's so rare that mechanics put these motors back together the right way unless they're specifically trained with the VQ. There's nothing special about these motors, but without the field service manual, you could miss some very crucial steps.

You need to take the car to a Nissan and get their opinion.

 

If it were mine, I would go to a thicker weight oil (possibly even add some lucas oil treatment) and run it until it knocks. Which could be tomorrow, or 5years from now. Just begin to set money aside for a used engine or rebuild down the road.

-Rob

 

How are bearings going to lower the oil pressure?

 

I won't go into great detail, but basically pressure is a function of flow/restriction. Bearing clearances make up the majority of the restriction (pressure) in the oiling system, cam, rods, and main bearings. As bearings wear clearances increase thus causing less restriction and loss of pressure. Oil pump performance typically doesn't significantly diminish over time, they usually just fail entirely, In almost all cases loss of pressure is caused by increased bearing clearances (worn bearings) or a oil leak on the pressure side of the system.

-Rob

 

Got ya.

The part that is odd in this case is that his motor w/ just over 115K isn't really that high. To have bearing issues seems somewhat premature to me.

 

All depends how well the car was maintained, Mileage means nothing if you don't know the maintenance history. If oil is not changed in proper intervals, or if starvation of the bearings due to low oil occurs it will cause premature wear, there are a number of unknowns which can cause such wear in even a much younger engine.

-Rob

 

Agree, it is probably not the pump.

 

if you need a pump I got one for sale. asking 70 shipped for the pump. I also have a short block available....I also have my Long block available if you were interested.....Short block im asking 500.00 for it. Long block im asking 1000.00. If you want the complete block to swap straight out I am asking 1500.00. has 94k on the block but has some upgrades. Unorthodox Crank pulley, Deleted idler pulley, Polished Timing Cover, Pathfinder cooling mod with powdercoated gloss black coolant pipes with deleted coolant lines.

 

hey do yourself a favor change your oil galley gaskets they are paper and cause pressure loss pumps rarely fail on these cars. the gaskets are located under your timing cover you will need to take the time cover and the upper oil pan off and thw you will see a almost y shaped channel its easy to do and you dont have to **** with your timing