rotarypower86

I am having problems with my n/a rx. Please read and see if you know what is causing this. This is what happens:

VERY Rough starting (cold, and warm somtimes)

It backfires or pops when you get off the gas

VERY inconsistent powerband/power stinks

Major loss of power from 3800-5000rpm!


I set up some LED's for the error codes from the ECU in my car. I didn't get any codes except when decelerating (in gear):

1 long, 2 short = Pressure sensor (This always happens above 4krpm, decel)
and
1 short = Crank angle sensor (only happens sometimes; Can't figure out why)


If you can show me the right direction to go in I would really appreciate it. Thankyou!

-Charles

rotarypower86

bump^

sleejay

check to see if your secondaries are opening... lots of what you said totally sounds like plugs / wires... try replacing them.

rotarypower86

Secondary ports? -They are opening. . . I have new magnacore 8.5mm wires and plugs.

sleejay

timing timing timing
check it and fix it... if its on, its your tps you can search on here to see how to set it, i reccomend the multimeter method and not the crappy lights....

classicauto

iTrader: (3)

does the car smoke any terrible amount?
burn any fluids?

RotaryWeaponSE7EN

iTrader: (6)

Throttle Position Sensor.

5252

Do a compression test and post up the results.

Chimera747

check your fuel pressure, if it isnt up to specs replace it, at 3800 the secondairys open and the pump cant keep up if it is going bad

rs_1101

do a compression test.

do a full tune up.

rotarypower86

I have a new/used working tps. I set it right. . .

the car doesn't burn any fluids besides oil, of course.

I'll check the fuel pressure. If it isn't up to spec, should I replace the fuel pump or what? If so is there an preformance aftermarket one that anyone recommends?

I had a compression test about 20k miles ago when I bought the car. . .(at mazda)

thanks for the help,

Charles

Innovation

iTrader: (1)

Let us know when you find the problem, I'm having the same issue. Check all your grounds as well. I found a bad ground which improved performance a little but still have a miss only under load.

rotarypower86

Ok last Saturday I finally had a chance to try to fix the problems. I bought a timing light and the timing was way off. The timing was very inconsistent too. I adjusted it to the stock setting. Look at the attachment, where the old bolt marks were. Now, the low-end power is MUCH better! It doesnt bog donwn! The power fade at 3800-5500 is a somewhat better. It'a still there though.


Now my idle is a little high. (I did adjust the tps)

Starting the car is still rough too!

It still pops, but not when driving as far as I know.

I don't know how to do a compression test. . . (My engine only has 31k miles on it, too) I think I will check the fuel system pressure, and such next.

I will post anything else I find in a few days. (no internet at home )

Thanks,
Charles

RexRyder

iTrader: (10)

if the power fade is at 3800, thats when the secondary injectors open? maybe its that???

rotarypower86

Yes, but, my secondary ports are opening. As for the injectors themsevles, I have checked them with a multimeter (at the ecu), they seem to be ok(maybe not), but I don't want to spend $200+, and it not do a thing. So I am looking for other thing to look at first.

RexRyder

iTrader: (10)

Secondary injectors, have nothing to do with secondary ports

try checking them at the injector itself, and post your results

so are they ok, or not? if not, then that might be your problem.

Spend $2+ on a bottle of fuel injector cleaner 1st. and N/a injectors are a lot cheaper than 200, you just gotta kno where to look.


injector cleaner.