RX7FROMCAL

WHAT THE HECK DOES THIS THING DO?? my car idles high sometimes then low some times when its in the low mode its like its struggling to find a good idle . i took the vacum line off the pressure sensor and the car idles great when that ******* not hooked up, need help here , im thinking the dam thing may be gone . what do ya think. thanks

1987RX7guy

iTrader: (3)

It outputs pressure readings to your ECU what do you think it does? Make fries? Cooks lunch?


Check yours using the FSM's spec.

Aaron Cake

iTrader: (1)

You have an NA, right? So you have a BOOST sensor and not a PRESSURE sensor. Go figure.

It tells the ECU what the current manifold pressure is. Essentially it's a load sensor...

Sounds like you have a bad boost sensor, bad boost sensor grounds or the little restrictor pill is missing from the vacuum line (or all three).

Icemark

or he has a mis-adjusted TPS and the extra vac from the disconnected line is stabilizing the idle.

RX7FROMCAL

i take it u have never cooked fries over a rotory engine , they are dam good man. lol

RX7FROMCAL

sorry for the mis spell of the pessure sensor , lmao<< pulling head outta *** here

Icemark

Fries??? Only Fries???? You have a rolling kitchen cook everything.

DemonicPupil

Poor car =( I always wanted to put a small oven in one of my cars so that I could cook during long drives. *chuckle*

philiptompkins

iTrader: (4)

^my dad's got this chrysler van that has a nice and flat intake manifold right on top, we reheated our left over pizza on it while driving to wal-mart once, worked great

NZConvertible

That may be what Mazda refer to it as, but anyone with half a clue knows what a load of baloney that is.

The industry term is MAP (manifold absolute pressure) sensor.

RX7FROMCAL

what this thing look like little restrictor pill, i know where it goes . i just have no idea what the shape of it is , please help . anybody have a pic. thanks

1987RX7guy

iTrader: (3)

Restrictor pills look like medication capsules but have a hole bored in them and are obviously not medicated :P

RX7FROMCAL

thanks man , where can i get one ?? because mines gone from my unit.

HAILERS

An orifice will effect the boost/pressure/map sensor during acceleration but not at idle.

You might have a turbo sensor in your car instead of a non turbo sensor. I've noticed if you have the wrong sensor in a given car, the idle will be unusual. Been there, seen that.

You can tell the difference in sensors by the voltage output with the key to just ON. A turbo will read like 2.3 to 2.7 volts and a non turbo will read 3.5 to 4vdc. At least on a S4 they will.

OR the sensor might be busted. PUt a vacuum hose on it and suck on the hose. The sensor should hold vacuum.

Or the problem could be another thing all together.

Tech_Greek

I can see it now, man sucks on vacuum tube, sucks up the pill and blocks air passage and chokes to death while working on his car...had RX7Club post printed out beside him instructing him to do so; there is a federal investigation going on as we speak.

RX7FROMCAL

its the stock na sensor, when the line isnt hooked up the car idles fine, when i hook it backup its like its searching and idle bogs up and down , im thinking the pressure unit its self is gone. gawd knows when the blower was on, and all the so called mechanics that worked on , no tellling what happen in the processes. what do u think????

RX7FROMCAL

do i have to go to the dealership or can i get this this resistor pill at the local auto shops.

Tech_Greek

I'm actually having the same problem, my pressure sensor isnt hooked up, its just when plugging a vac up on the UIM it idles like crap, but when I leave it unplugged it idles fine.

RX7FROMCAL

so being that we have the same prob , what do we do ????

RX7FROMCAL

will this hrt the car ? soesnt seem like it would being that it idles bettter , whats your take o this prob.

arghx

iTrader: (3)

Why do our cars have an AFM and essentially a MAP sensor? Seems kinda redundant.

Tech_Greek

Here's my take on it.

Our cars, well mine now, runs really rich at idle...you're pulling air via vacuum.

So, with that being said, it seems as if when I have my vac line off, it's sucking in the needed air to match the fuel flow and smooths the idle out.

So, I've got tomorrow off, granted it's not raining I'm going to go out to a old deserted parking lot and adjust all my settings tomorrow with the vacuum line ON so I can take away fuel at idle if need-be via SAFCII and mess around with that.

- Tech

NZConvertible

You can get it from the dealer for a few bucks, or make your own. Anything that fits snugly inside a 4mm vac line and has a 0.5mm hole drilled through it will work exactly the same as the factory part.

Most AFM-equipped cars also have a MAP sensor. The AFM is the primary load sensor used for fuelling and ignition. The MAP sensor is also used for further trimming of fuelling and timing, as well as other tasks like emission controls, the S5 NA's 6PI sand VDI and the Turbo's overboost fuel cut and boost gauge and the S5 Turbo's boost control.

RX7FROMCAL

im also dealing with a load issue , when i turn on my lites the tack drops wayyyyyyy down , but it doesnt stall it. ive checked all the ground hook ups . they all look good , the alts new, but that doesnt mean anything , my last one from the auto zone was bad to who knows. the volts dont seem to drop when the lite come on , but theres something going on causing this prob, any thoughts. thanks

HAILERS

The BAC adjusts the idle when there is a load put on the engine at idle, like turning the lights on or the heater or the air conditioner or the rear defroster.

The BAC does not sound like it's up to snuff OR the idle is not set right and is putting toooooo much of a demand on the BAC and the BAC can't keep up with the load.

So, I'd check the idle with the initial set coupler installed with the timing spot on per the FREE ONLINE, FSM. They won't charge you much when you download it.

If when you get the engine warmed up, and install the initial set coupler, and the engine then dies or almost dies...............then the idle is not set right. The BAC IS NOT meant to idle the engine all by itself. It's a helper NOT the sole item that maintains a idle.