I unplugged the O2 yesterday, and it no longer hesitates, per se, but it still goes into closed loop, at least i think. At the same piont the were it would begin to skip before it now dips into lean just a little, and then cranks back to mid rich. It 's better, So i'll try a new O2. I'll feel like a tard if thats the case, I read Hailers post about the O2, and rember thinking nah it cant be the oxygen sensor, the needle still moves on the gauge. I have A-ADD so I can claim common sense dosen't apply to me :P

-E

 

Boys and girls, we have a winner- it turned out to be the EGR block-off plate. As if we didn't know this before, aluminum, no matter how thick, has a different thermal expansion coefficient than cast iron, and I've proved it, lol...Evidently after warm-up it was flexing just enough to allow exhaust gases in the EGR passage to flow freely into the intake passages, thus causing my problems. Everything makes sense now, the O2 sensor freaking out, the hesitations when warm, the vac gauge jumping around...Although I have no idea why bumps had that much of an effect on it...

Also discovered something truly amazing, and contrary to everything I've read (and stated myself) on the forum- the 3K warmup system does NOT use the air bypass solenoid valve to do its thing. I left it off of the TB and plugged the intake passages, and removed the air bypass relay. First start, she goes to 3K again. Amazing...

I like to troubleshoot things, but this one kicked my ****, lol. So all of you running around with aluminum EGR block-off plates, keep an eye on it...Thanks for all the help and ideas, guys

 

YEAYYYYYYYYYYYYYYYY!!!!!!!!!!!!!!!!!!!! Good job man! no you just need to convince mazdatrix to take back your new fpr!!! That would have drove me crazy!

 

The airbypass works in conjunction with the bac to create the high rpms on startup on a stock car. Elimination of the airbypass solenoid should have resulted in a somewhat subdued rev. Usually just 2200 to 2500 rpm.

At least tha'ts my interpertation of the thing. Did you count the seconds it endured? Seventeen? Without the air bypass solenoid?

 

https://www.rx7club.com/forum/showth...tionship+chart

AWS and airbypass solenoid are the same item. Put your monitor on its side to read the chart. That's the way I do it. humor https://www.rx7club.com/forum/attach...chmentid=20257

https://www.rx7club.com/forum/attach...chmentid=20262

https://www.rx7club.com/forum/attach...chmentid=20256

 

3K, Hailers...The smoothest 3K I've had in a while, too, lol...And yeah, the usual time, however many seconds it is (I'm not that **** that I sit there and count). Hey, it shocked me too, here I was trying to disable the system for good, lol...I don't like the idea of disconnecting the rad temp switch, because I have a feeling the ECU does more with that input than just the 3K wamup trigger...

Honda dude- my FPR is nice and shiny now, I'm not going to give it back

 

Wayne - Cool that you fixed it.. I still think you should do a teardown and reassemble the engine just to test it for good

In unrelated news, my car is definately working properly.. I just did a 100 mile run last night, a large portion of it above 80 mph, and my temp never got more than 1/3 of the way up the gauge... I still want to get a good aftermarket digital water temp, so I can monitor it exactly, but that will have to come later. Tomorrow: Autocrossing

 

We pulled the EGR and put a plate over it and I believe it made all the difference in the world. I'm a little skepticle since I've tried everything as well but I didn't feel any hesitation. What are the advantages of or disadvantages of removing the EGR?

 

Technically, mine's been removed for a long time- the solenoid that controls the actuating vac to the valve anyway. The only disadvantage to removing it (or disabling the system) is the emissions testing, if you have it.

Watch that plate carefully. I plugged the orifices in the bottom of the valve itself (just in case the internal plunger decided to crap out and route exhaust gases continuously into the intake), and reinstalled the valve again, because structurally that valve body is much firmer than the block-off plate I had on there. Hooked a vac hose to it just for show

Cool, so you nailed your problem, too

 

I'd like to say it's working fine...time will tell. I've only driven the car for about 20 minutes since the work was done. I just want to thank you for your hard work and sharing it with the rest of us.

 

BTW, I've been meaning to get back with you on the 3K thing without the air bypass valve installed, Hailers...

She's still doing it, so I'm letting her, lol...Sometimes she'll do 2800, sometimes 3200, but mostly right around 3K, and the 17 or whatever seconds alloted for this particular rotary oddity. The vac stays at about 17 during the 3K thing, which is where it sits at idle, and that kind of trips me out, but she's running great now, so I'm not gonna mess with her. About to hit 10,000 on the rebuild any day now...