Hesitation on cold drive 03 350z
 

Hey guys as the title states I'm having a weird issue with my car. Recently I did a little work to my car. Eibach sway bars new tailights headlights some new struts and an oil change. When I drained the oil it has pretty low. Had maybe 3qts in it..anyway I replaced it with 5w30 royal purple. 5.6 quarts. After checking my oil it showed a quart over...so I drained a quart checked it again and it showed perfect...so after I took it down the road it had a bad hesitation between 3-4k rpm... Oil pressure also flew way up to 120psi it almost seems like the car had to much oil in it... I guess I'm just trying to ask what I should go about doing now...I've searched but I can't find anything matching my issues.. Also forgot to mention I changed my spark plugs they looked pretty bad. Almost like the car was running lean...any advice would be awesome
https://cimg9.ibsrv.net/gimg/my350z....a86d482926.jpg

Where to start.

Oil pressure has nothing to do with amount if oil, more with oil viscosity and temp. The only time you will get a pressure chance from quantity is when you have low enough oil and the pump sucks air.

I could be wrong, but I believe RP is still one of the crappiest oils on the market for a VQ

Most cars run lean from the factory under normal loads for emissions reasons

Aftermarket tail lights and even tail light bulbs have been known to cause problems with the ECU. Normally it's limp mode, won't rev over 3 to 4k

Hey man thanks for the reply. I live in tn so the weather is pretty steady. Normally gets to about 90° during the summer. I'm running 5w 30 like my book stated and the royal purple I didn't know was bad....the limp mode could be a possibility but it goes away after its warmed up and driven for about 10 mins

Any codes?

None at all

Something I didn't mention. When I did my oil change I used 5w30 royal purple full synthetic and also a quart of Lucas oil stabilizer

Bump :/ still having issues

I would suggest try putting the OEM tail lights back in and see if you're still having issues.

If they're LED ebay/aftermarket/non-OEM spec and you're not running load transistors, that could be the source of the hesitation problem.

Oil sounds like a separate issue.

OK thanks. I will try it as soon as I get home. Only things is it goes away after the car runs for a little

Why would you put in "5.6" qts when the capacity is 5qts as stated in the manual? I sure hope you added 5qts of real oil and the extra 0.6 is the Lucas.

Either way, drain it out and fill with 5qts of just motor oil (a bit less if you don't change the filter again). If your motor doesn't run right without any additives you have bigger issues. Plus it clearly states that Lucas "Raises Oil Pressure" as a benefit on the site.

And to allay your fears, VQs burning oil is not uncommon, especially earlier ones. To remove 3qts is not abnormal (actually, if it only burned 2qts in 3k miles, you are on the lower end of the oil consumption scale), just says that the oil level was not periodically monitored and topped-up by the owner.

Thanks man. I'll drain it and refill.

So I just tested the taillights to see if that caused it and it didn't. Still extremely poor performance...

So I drained the oil and replaced it with 5w30 castrol edge. Took it down the road and its still doing really bad. Hesitation is at 3500-4200 rpm and then it kicks in and goes but its almost like its in nuetral when I hit that rpm range.. I cleaned the maf sensor and the air filter... I'm lost on what next any help would be awesome. Thanks guys