I have a question im hoping it could get answered here , i have a 2007 350z 6 speed manual base, with 88k miles 6 months ago when i did the oil change for my car ( i always use mobile 1 except for this 2 times ) at low speeds say 42 mph in 2nd and 3rd gear the car would jerk a little sorta got the feeling the car was struggling because of the oil, so when i went back to mobile 1 the jerking went away so from then on i kept on using mobile 1, my last oil change tho i got a different brand synthetic oil and the car started doing that again so i was wondering if i have to stick to one kind of oil, maybe the oil that was put in my car is to thick ???? i dont know im hoping some one with knowledge can tell me whats going on next oil change which is in 1k miles im going back to mobile 1 o and by the way the jerking is not all the time it comes and goes, and its not a violent jerking but you can feel it when it jerks, if i speed up the jerking goes away i was thinking mmm maybe its the clutch but ive already done clutch testing and the clutch is not slipping or anything like that so im blaming the oil for maybe being to thick what are you guises thoughts.

 

its not the oil, i can tell you that much.

maybe your flywheel is bad. the springs break.

does it jerk when you try to accelerate?

 

Oil brand is not the same as oil weight. That being said, oil is not the problem. Are you sure it isn't in your head?

I like Mobil1 filters, but I'd never run their oil in any of my vehicles.

 

it only does it some times and at about 42 mph it feels like when your teaching some one how to drive stick when they are about to stall the car except my car doesent stall its the jerking and the jerking is not violent but you can feel it im starting to think its my flywheel and clutch i already ordered one yesterday JWT its had the original clutch since 07 and i beat it up once in a while not all the time . but whats very strange is 6 months ago it was doing the same thing on the same clutch when i switched to some other oil and once i went back to mobile one the problem completely disappeared. the oil i put on is valvoline cuz it was on sale and i just had to get it.

 

When is the last time you cleaned your MAFs?

 

I have an 07, and mine does this too. IIRC, it has something to do with the weight of the oil, i heard you can get a new ECU from the dealer, and it will go away. This happens to mine before its warmed up.. if i let it reach op temp, it doesnt do it. I run Castrol 0W-30 European formula and bosch filter btw.

 

Read his posts. There's no way he has a clue what MAFs are...

 

Lol..

 

Very strange. It sounds like a transmission problem. I think it's best to contact a mechanic.

 

This 'problem' is ridiculous. There's no way a different brand of oil will make the engine run rough immediately after it's changed. Somebody is jerking somebody else's chain.

 

I changed the oil problem went away thanks for helping me out guys / thread

 

And it wouldn't do it when I started it up it would just be out of no where it's the oil because now that I changed it it hasent done it. Mobil 1 ftw and I'm not putting gas from gas76 station went back to chevron and btw there was no cel on or anything g it's just bizarre but hey problem went away

 

No way it was oil unless it was two years old or low.

 

Lol believe it or not ! Changed oil no mo jerking.

 

You do realize Mobil1 is sh*t in the VQ engines, right? Do some research; it causes the most wear.

 

In order to prove the oil is causing the jerking, you'd need to (1) identify exactly what condition is causing the engine to misfire (fouled plug, bad MAF data, or whatever), and (2) show how the oil caused that condition.

Plugs don't foul instantly, and then instantly clear themselves up. Ditto for MAF issues. Ditto for anything else. Thousands of people are probably using Mobil 1 in the same engine without this problem.

 

This can happen with the wrong weight oil, I have seen it personally on my car. The issue is the VVT actuators hunting for the proper adjustment. If you have intakes you will hear the engine tone change when you feel that surging as well. It's painfully obvious if you are using a heavier oil than spec'd and it's cold.

Oil pressure is just too high and when the car tries to move the cams it gets more angle than it should, then has to back them down. This back and forth cam timing swinging is what you feel as a 'jerking/surging', because the engine airflow is changing and therefore the torque output varies.

 

That's a pretty well-reasoned explanation, but I'm still skeptical. Unless the OP put in a MUCH heavier or lighter oil, the cam VVT mechanism should be able to handle it without hunting/surging.

Surging and jerking aren't the same thing, and the difference is important here.

 

If i'm not mistaken, according to the VQ oil analysis. Mobil 0w-40 was one of the best performing oil for the VQ.

Mobil 5w-30 not so well.

 

I thought Castrol Syntec was highest?

EDIT - https://my350z.com/forum/engine-and-...-and-info.html

Castrol and Amsoil are on top. Mobil 5/30 is garbage, 0/40 is ok.