I've been told about a VVT tuber per se'. It's where the actuator valve that called for replacement via the service bullitin. I'm going to blow it out with carb cleaner.

The only reason that I am leaning towards the CAT being clogged is that
others that have had ignition problems have had to replace their CAT converters shortly afterwards. Trust me, I'm not excited about throwing money at a problem and seeing if it will fix it.


Next up, Changeing out the coil pack. By this point I would think that teh car will have a littel bit more umph...

 

IMHO/IIRC, The majority of the problems of the ignition/converter you speak of were with the NB1 (99/00) cars and their coilpacks going bad (pretty common), which would cause raw fuel to get into the cat and superheat the element and eventually blow it out. I have not really heard of any problems with the NB2 ignition and this issue.

 

Yeah the 01+ coilpacks are much better. Cats fail when the car runs too rich for too long, which is why a failing coilpack kills the cat.

 

I'm changing the cat next week. If this car doesn't get any more power or torque than I will be saying goodbye to miatas forever.

 

Wow, you're easily discouraged. Maybe making a slow car fast isn't for you.

 

He's not even boosted or considering boost. He just has a stock Miata.

 

That was my point, if he gets discouraged this much diagnosing his stock miata then he should not even consider adding the complexity of a turbo setup and standalone EMS to the equation. Stock cars are easy to diagnose.

 

You may very well be right. Some guys LOVE to build. Some guys love to polish. Some love to brag about what beats what compared to the latest car and driver mag... I like to race. My car set up skills suck. You would think that after racing for the past 35 years I would have learned a thing or two about car set up and such.

Some people say that this car runs perfectly fine. I disagree. It has more power hidden inside and I need to unlock this power before I even think about going FI.

Once I figure this out then I'll start working towards either a Winter build or a good person to take it to for a turbo install.

The only way I'll go FI is if it's plug and play. I'm not teh guy for remapping fuel curves at teh start line. And I hate it when a car leaves me stranded.

I've owned two supercharged Corvettes. Both L98 C-4's and both were a nightmare. Tubes comming off all the time. Limp home mode. Incorrect air fuel- blown motors. Swore off of boost a long time ago. But I've heard that you guys have the turbo kits for a miata down to a science.

I hope that this new CAT will open the car up a bit. I currently own two miatas, a 91 stock with 198k and an 03 vvt, guess which one is currently faster?

I need to change this.

 

Well, yes. But it is a science. Are you actually interested in learning? Your post makes is sound like you may not be.

And guess which one is lighter. With the exception of the Mazdaspeed, Miatas did not get appreciably faster through the years. They got heavier and a bit more power was added to compensate. I would not change the cat unless a backpressure check or visual inspection showed that it was bad. Could easily be a waste of money.

 

Maybe try finding someone local who knows Miatas very well and have them take it for a spin?

 

Definitely. Perhaps you could temporarily wire the VCTS arm open and test drive it to see if the car feels better. If it's staying shut the car will definitely not build any power.

(I ditched it completely on my car, removed the butterflies, pulled the shaft out and epoxied the shaft bores.)