fxpthl64

Interesting sixshooter. Does that hold true of just high mileage cars or is it good for normal mileage cars too? Better than most synthetics as well? How long should 90miata keep that oil before changing it back? Always, ALWAYS change the oil filter when you change the oil,no matter what! No sense in having new clean oil going through a dirty filter!

fxpthl64

Hey 90miata, I just viewed your four photo's and your car looks great. It has obviously been taken care of! In the gas station shot I noticed that your headlight covers looked to be in need of minor adjusting. I have found that if you pull up the cover on the hood-side you can make flush with the hood. Also, in the dashboard view the photo came through upside down. My guess is that maybe you took that one with an Ipad, giving that view. Looking forward to discovering what you find out about your "noisy" engine.

sixshooter

I have been using Rotella T6 in everything except my boat and lawnmower for years. My engines never seem to wear out and stay very clean inside. Almost all of the Miata turbo guys use it because of the better additives. If you are truly interested in oils and want to spend some days reading, bobistheoilguy.com is the leading resource on the net.

90miata

Yes It is in pretty great condition for a measly 2500 bucks in my opinion. The guy that owned it was one of those guys that is always away from home so the car was always just sitting in the garage. I was so happy when he finally said I could take it off his hands.

90miata

Ok so some good news and some not good news. The noise I believe was coming from the new exhaust I installed. One of the rubber hangers split and the piece that goes into the hanger was vibrating against the underbody. Got that all fixed up. But then the weird feeling when taking off got worse. Not really sure how to explain it. It started off hesitating I guess in the lower rpms. Not real bad but felt like the power was gone for a split second then back to normal. Today I took it for a lap around the block and when I took off it hesitated so bad it almost stalled. It was bucking and felt like it had no power.
I wish I knew more about cars so I could explain better. If anyone has any ideas please share. And again it was only doing it at low rpm. Once it gets above like maybe 2700 rpm it runs normal

sixshooter

Do a compression test, check for vacuum leaks, See if the AFM door is sticking, clean the IAC valve, read the spark plugs and tell us what they say.

90miata

I started by checking for vacuum leaks. I found one black hose that had a crack on one end and was pretty much crumbling apart on the other end
. I put some tape around both ends just to see if that helped. I didn't feel any hesitation after stopping and taking off a few times. Would anyone know what that part is called so I can buy a replacement or does it even have a name?

90miata

Took care of the minor adjustment on the headlight covers. Thanks for pointing this out.

fxpthl64

That hose coming out of the valve cover looks like a "PCV" hose but I don't see the actual valve! The "positive crankcase ventilation" valve helps to re-burn any vapors coming from that area and then put into the intake for re-burning. It is NOT a vacum hose so should not have an effect on the engine performance UNLESS it was totally blocked with sludge. Glad to hear the quick fix on the covers worked for you. Hope your investigation turns up something minor.

90miata

Isn't the pcv valve on the other side of the valve cover going into the intake manifold? And I'm guessing since that's not a vacuum hose that my problem isn't really fixed. I'm going to test drive it again when I get home and see if it does it again. Maybe it just felt like behaving when I drove it this morning.