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I've noticed that my mileage gets much worse if I'm going over 70, which is about 3200 or so, but today I was doing it with the window down and I could smell it! first I thought the old motorcycle in front of me was running rich, but then I realized it was me! is it just because my engine could use a rebuild, or is something else going on? what is it that's different above 3200?

after 3200?!...

The deep dark baffles of HELL open up, and your B6 exuberates incredible amounts of Bad @$$ness!!!

really though sounds like your VICS are running open.. are you running a SOHC or DOHC?

OBDII B6DE?

It starts to run open loop, ignoring O2 sensors. Verfied with a real time OBDII reader. Keep it under 110kmph.

Josh wrote:after 3200?!...

The deep dark baffles of HELL open up, and your B6 exuberates incredible amounts of Bad @$$ness!!!

really though sounds like your VICS are running open.. are you running a SOHC or DOHC?

sohc 93 5 speed

Ryan wrote:OBDII B6DE?

It starts to run open loop, ignoring O2 sensors. Verfied with a real time OBDII reader. Keep it under 110kmph.

so is this pretty normal then? I mean, I can understand the fuel consumption going up some, but to the point you can smell the exhaust while you're going down the freeway? maybe it's still putting in the same mixture it normally would, but since it's worn out, it's not burning it as completely?

As a SOHC, I don't know anymore. I only know it for the DE motor.

Its possible you have a leak further up in your exhaust system, a worn out catalyst, a worn out motor...

Ryan wrote:As a SOHC, I don't know anymore. I only know it for the DE motor.

Its possible you have a leak further up in your exhaust system, a worn out catalyst, a worn out motor...

That would be my guess, I don't think the SOHC has an EGR, my guess would be a exhaust leak.

Ryan wrote:OBDII B6DE?

It starts to run open loop, ignoring O2 sensors. Verfied with a real time OBDII reader. Keep it under 110kmph.

just for my own info, does it run open loop at idle too? I don't know all this computer stuff.

as I understand it, the O2 is open loop until the engine reaches operating temperature... or if it's faulty it'll stay open loop, or it won't stay in closed loop when it's supposed to. A faulty coolant temp sensor will also cause it to stay open loop. All this can affect your emissions and cause you to run rich.

A dead cat smells bad, as does a faulty catalytic converter. (da-dum... pshhh!) changing your O2 sensor and replacing your converter may clear up the smell.

On the B6, the most common exhaust failure is right on the curve of the downpipe, before the catalytic converter. you may want to have a new piece of exhaust welded in place on the curve.

it's not a huge deal to me, as I don't get up to freeway speeds with it very often anymore. I'm reasonably sure that I have a small exhaust leak where the manifold (header?) bolts to the rest of the system, it's not noisy or anything. that's probably why I can smell it, but I imagine that what I'm smelling is probably just due to my engine being worn out. oh, well, I don't really care that much right now, it runs well enough at the lower rpm's, I'll just keep on driving it until I can afford to rebuild (or swap) it.

-edit-
being worn out is probably why it runs out of breath around 5500 rpm's, too, right?

myfirstmazda wrote: -edit-
being worn out is probably why it runs out of breath around 5500 rpm's, too, right?

Its probably just because its a SOHC B6

4800 RPM's you start losing HP and your torque planes out. 5500 you start drastically losing HP and torque. SOHC is really a pathetic engine :S

yeah, it feels best between 3500-5500 as far as acceleration goes. so that's a sohc thing then? I kinda thought it should be good to 6 or so. I was wondering about swapping a b8 sohc instead of the bp so I don't have to mess with wiring things up, does the b8 behave the same way?

What wiring things?

If you can't handle 3 wires.....

I can, I just don't want to.