Engine bogging down with any swift throttle change

[JustJeff]

I'll keep all of this under advisement

What about using one of the fittings on the back of the TB for my boost gauge. I'm trying to remember what is back there. Large one feeds my OMP injectors via the splitter. I can't remember where I routed the other two, but I'm going to need to take the UIM off and look over my vacuum routing anyway.

Also where can I buy those orifices/pills for the vacuum lines (sorry I'm still working caffeine into my system so my thinker isn't too good ATM).

[RETed]

No problem using the fittings off the back (or the front) of the UIM.
I don't remember which one was which, but on the front of the UIM, the top and bottom fittings see vacuum - the middle does not.
In fact, if using a boost sensor or boost gauge, it's better to use those, cause they take vacuum off the surge tank; there is less chance of pulsations from the alternating front and rear rotors.

I dunno if Mazda still carries those pills, but I didn't bother with them.
The pill is to keep spikes from getting to the boost sensor, so the stock ECU doesn't trigger the over-boost fuel-cut unnecessarily.
If you have an FCD (or some way to defeat the over-boost fuel-cut), then this is not really necessary.


-Ted

[Pete_89T2]

Originally Posted by RETed

I dunno if Mazda still carries those pills, but I didn't bother with them.

The pill is to keep spikes from getting to the boost sensor, so the stock ECU doesn't trigger the over-boost fuel-cut unnecessarily.
If you have an FCD (or some way to defeat the over-boost fuel-cut), then this is not really necessary.


-Ted

I disagree with removing the restrictor pill from the MAP sensor line. If you do, a side effect is it will cause the MAP sensor to produce a "noisy" signal even at idle, which can effect your ability to tune the car. I have an Rtek 2.x modified N370 stock ECU, and when I was having Dave B. at Speed1 tune it for me, he initially had problems trying to determine my baseline on the 1st few dyno pulls. He noticed the MAP figures showing up in the Rtek logs were all over the place. Then Dave figured out I was missing the restrictor pill, popped a spare one he had into the MAP sensor line and all was good from there - MAP readings in the log were no longer noisy, and he was able to get a consistent tune from that point on.

BTW, you can usually find generic restrictor pills for 1/8" hose at Advance auto parts or Autozone.

[RETed]

It's odd that it'll affect the RTEK...
The stock ECU uses on open-loop process for idle, so I would think it would ignore the boost sensor signal.

I've gutted the stock ECU a long time ago and have been running a Haltech E8 for years now.


-Ted

[Pete_89T2]

Originally Posted by RETed

It's odd that it'll affect the RTEK...
The stock ECU uses on open-loop process for idle, so I would think it would ignore the boost sensor signal.

-Ted

That's true, what I meant to say was that the MAP sensor readings we saw in the Rtek logs were noisy even at idle; idle itself was smooth and steady. When doing the baseline dyno pulls, we couldn't get consistent HP & torque numbers from pull to pull, so after checking the logs, it became obvious that the noisy MAP sensor readings was the cause, and the restrictor pill solved that problem.