Exhaust problem? Power band?

[Bvisailer]

Anyone have a problem with installing a header? Ever sence I installed it my car acts like it has a power band. No mid range acceleration then all of a sudden I get a bunch of power. No vacuum leaks. I did the non foulers in the O2 sensor. Both set of butterfly vlaves in intake move freely. Cruising lightly at 60 no acceleration it feels like its got a trailer behind it. Barely accelerate some and feels like power just kicked in. Any idea? May try and load video later

 

[Bvisailer]

O. And if I rev it up and feather it from dead stop and accelerate hard. It pulls perfect through every gear. Then go to cruise at 60 it does what I explained above

 

[Maxx Mazda]

Did you non-fouler the primary O2 sensor? You're not supposed to.

 

[Brian_K]

how old is your primary o2 sensor? I had similar problems and went through all my vac/fuel related stuff before replacing the primary o2 sensor which fixed everything.

 

[Bvisailer]

Primary is in by itself right where the four pipes meet. Only nonfoulered the secondary. And the sensors are the same when I got the car close to a year ago. $100 for both tho :-/ already dropped a few $$$ on appearance parts. If I had known this would happen i wouldn't have and just replace them. Figured they worked perfectly fine before header was done.

 

[Brian_K]

you should only be concerned with the primary, the secondary doesnt do much of anything since it's screwed into the nonfouler. if you've already gone through everything else you might want to look into replacing it. my old primary o2 sensor made my car run like s***, but never threw a check engine light. after i replaced it, it was a night and day difference.

 

[Bvisailer]

I will definitely be getting one then. I'll try it out Monday when I get back and let y'all know how she does.

 

[Theycallmepnts]

Im also experiencing similar symptoms. My primary looks pretty rusted and original. Bosch seems to be the accepted replacement?

 

[Bvisailer]

Going to buy one today. Bosch is the best replacement? Would denso or a universal work? I'll pay the extra for bosh if it will ensure it works properly.

 

[i12drivemyMP5]

If I paid extra for anything it would be the Denso that it came with originally................

 

[Bvisailer]

i paid the extra and got the proper o2 sensor for it. started up cold. acted like it should. smooth rpms. after about a min. i started to hear a skip/missfire. i let it warm up alittle more and started to rev the motor. it sounded like a subaru accelerating. had a dead miss all the way in the high rpms. let it idle down and it still had a random skip. no CEL. gonnna drive it some in a few and see what she does. may do the same thing. be completly fine when accelerating hard but terrible when cruising. i just noticed to do have a leak at the EGR tube and header pipe. not sure if a slight leak there will cause anything. it was a pain in the ass to bend that pipe to match up with the tube. may just need to take it off and properly done. but before i do that and spend all that time i need to know if that may be the cause of all this. i really dought it but thats why im asking. yall know alot more about the mazda 2.0 then i do. thanks again guys

 

[Maxx Mazda]

If you have any kind of an exhaust leak, your knock sensor could mistake this for knock and the ECU will pull a s*** load of timing which MAY give you what you're experiencing. How is part throttle operation at increased RPM's?

 

[Bvisailer]

It's smooth. But every so often it will miss. Going to fix exhaust leak tomorrow. Go ahead and cancel that out.