wam

hello peoples....im kinda new to your site..so here is the problem...i have a 88 convertible with 185,000 miles..it runs great, but it seems to be a little low on power...ive done the atf trick, that helps for a while, but then it right back haveing not much power...also around 4000 rpm its looses a lot o power...it dose not seem like it wants to rev up like it should...ive owned a few of the cars, and this one has the least amount of power....also it seem like it wants to run a little hot..im going to get the rad. boiled out and see if that helps....but back to the above 4000 rpm...the exhaust gets real quiet about that rpm.....seems odd to me...i have more exper. on the 12a's these fuel inj is little above me right now..but im learning....so what i was going to do is take the cats off and gut them, or maybe put on a "test pipe" and see if that mite be the problem....any i deas??? thanks. wam

Icemark

You have a 13B in that car, not a 12A... 12As in the USA were carbed.

Anyway

A couple of things come to mind from your description...

#1. yes, probably clogged cats. You should order a Bonez High flow Cat and down pipe. 'verts are very stinkly without some sort of cat. Most factory cats have a life around 100K-120K miles. Not too many of them are in good shape much past that.

#2. 5th/6th ports are more than likely stuck closed.

#3 secondary fuel injectors may be clogged.

#4 fuel filter is probably clogged.

BoostedRotors

I believe he meant that he had more experience with the carbed 12a, and that the FI 13b is out of his league right now.


Also, Id suspect the cats...5th and 6th ports and the fuel filter as well. good luck!

wam

yes i hope its just the cats, ill remove the exhaust system this weekend..so how do you "unstick" those 5th and 6th ports...and hmmmm where are they....like i say..i sort of like the 12a's better....very easy to work on..but i belive once i get the hang of this, it want be so bad! ill check the fuel filter, and a few other things....thanx for your help BoostedRotors and Icemark!

Icemark

To unstick the 5th/6th ports you will need to pull the intake manifold and soak them.

You'll need upper and lower intake gaskets, and more than likely replacement oil lines. If you havn't replaced the pulsation damperner you may want to do that at the same time it is all apart.

Figure $100 parts w/o the PD and $250 parts with it.

BKC TURBO

clogged cats can really hamper these cars. I just take em off. someone said the verts need some sort of cat, i wonder what's the diff?

Barwick

does the S5 TurboII have 5th and 6th ports too?

Icemark

Try driving with your hatch open and no cats... see how long before the fumes kill you

a 'vert is that way everytime the top is down

wam

so, hmmm... i have a vert, should i just go and get some new cats instead of removeing them because of the fumes??? or should i just remove them all togeather?? maybe a free flow cat???

Icemark

personally I would be doing the cheap stuff first, like checking the 5th/6th ports (you should be able to turn them by your hand) and replace the fuel filter.

Then if you are still having problems, then approach the cats.

If you have a downpipe and cat replacemnt pipe handy then you can try subsituting, but if you don't you'll be spending moeny on something that you are not sure is the problem.

BTW: you can get a highflow cat at RX-7 store cheaper than buying new stock ones.

wam

thanx Icemark. but will the 5th and 6th ports stopped up, make the car run a little warmer. like 3/4 the way on the gauge.. i put aftermarket temp gauge on to see what it really was....it runs about 225 on the hiway and about 190 in the city..its got a 180 t-stat in it...but what i was thinking is that the radiator mite be sort of stopped up. i mite remove it anyways and get it done, and i also got to replace the oil coller lines...they are leaking very bad... im going to order some gaskets from victoria-british..advance auto, and autozone dont seel any gaskets at all for these cars. (well not here anyway) but im very excited to learn these 13b's...they are a handfull!!

Icemark

a 180 t-stat????

sounds like you are not using a Mazda OEM thermostat.

That alone can be your running hot problem.

wam

well i took it out.. its the stock one it has 82 degree c. i guess it was 180??? i tested it..it was all good.... but what is the factory degree on these 2nd gens??

emagdnim

Don't be a wussy! Who cares if it stinks? It's faster!

darkwaveboi

i hope you realize just how stinky it can be. I have my pre-cats still there (may be source of power loss from cloggage..the main cat was beyond gone when i took it off).

pre-cat back all i have are straight pipes and sometimes i feel bad for the people behind me haha..boy when im at a stoplight, that **** overwhelms you with nastyness. It is also VERY noticable..so if your in a place where the cops know what un-catted cars smell like..you can be smelled from 2-3 cars back.

Jef