So I got one of those bluetooth things you plug into the OB2 spot or w/e.

And with Car gauge pro you can check A/F ratio's in both banks, at least I think. Says like "alpha fuel bank 1/2" And has a percentage thing for the reading.
Said it was getting about 87%-97% at like 1,500k rpm and up, shouldn't it be like 100% at least?

Anyway IF that's what it is, I've been having problems with top end since I got the car 2 months ago. After about 80mph it just CRAWLS, I couldn't even get it to 110. I even have the 6spd!

I had a 4th gen that got to 137mph with 3 people in it fairly easy I might add.

So I was thinking maybe the fuel filter's clogged or slightly clogged?
I think the injectors are fine. In the app both injectors were getting the same msi or whatever it is.

It's got 140k, catback with testpipe, 2' timing advance, NWP block off plate, offbrand air intake system, new knock sensor.

 

Sounds like a bad power valve. It is a valve for the variable intake. They are made of plastic and sometimes the end point that connects it to the solenoid breaks off. When this happens the solenoid activates to open the long runners in the intake (I think around 3500 RPM) for more top end power. But if it's broken the valve never opens and stays on the short runner intake.

You can check this by removing the power valve solenoid assembly. Be careful as those Phillips screws are very very soft. I changed mine over to Allen wrench screws.

 

Do I even still use that if I have the VIAS block off plate?

Or is that power thing a different matter?

 

nope and nope

Time for the best mod in the world (headers).

Narrow band O2 sensors are worthless, so I'd ignore anything it says for mid-high rpms.

 

Haha, You think my cats are clogged or what?

I planned on getting headers but I've heard you more or less HAVE to get the same brand y-pipe/headers otherwise they may not fit.

I wanted to get OBX headers but also heard they're almost impossible to find.

 

That would be my guess. The faster you go the more load is placed on the engine. If it is choked it would be most noticeable at high speed.

How does it respond like in 1st and 2nd gear? Any other symptoms?

Headers come with a Y pipe. Find used cattmans or obx or just gut the cats.

 

Close. The VIAS is always open unless the engine is between 1800 and 3600 RPM. Here's some info from the FSM:

 

Ohh, I see.

1st & 2nd are real peppy actually. It's when you get into 3rd it starts to slow down.

I used the timer that our cars have in them and my 0-60 was only about 7s... Which according to most places is suppose to be like 6.1.
And everything goes down hill from there.

I do have a High voltage code for my bank 1 sensor 2 o2 sensor tho, if that makes a difference.

 

^



o2 sensor is rear one so doesn't affect A/F ratio

 

Ok, well that sucks.