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How to check ECU pins?...

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Old 11-06-06, 02:12 PM
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How to check ECU pins?...

It seems that I can't get my DMM's probe to go into the ECU-side connectors... when I try to put it in, it just pops open the little flap that holds the pins in... and even if I take it off the ECU and try to put it in the other side, it seems that it's too big to really get in there good... are there any good ways to make a good connection with the ECU plugs? Because otherwise it's telling me there's no continuity when I know there almost certainly is.

I'm still confused to hell as why it would think the pressure sensor was bad, despite the fact that the voltage is correct for approximately 100 mmHg (if you get voltage from the ECU on the sensor side (from the sensor to the ground), how in Bob's name could it not have continuity?

It seems that I'm missing the orifice (I could have sworn I used to have one, maybe I replaced the hose and forgot about it...) so I tried zip-tying the hose a bit, and it seems to have restricted the air a bit, but probably not. But then again, if the voltage is correct, and theres continuity, why would the code still be there once I reset the ECU?... I would imagine if the actual sensor was bad it wouldn't flash the CEL until I ran the engine again (and hot the spot in the throttle that makes it light up). And I haven't run it yet...

But then again, if I've been missing the orifice for that long, why didn't the issue show up sooner? Maybe because of the weather? I can't really imagine that the orifice (restrictor pill) would just disintegrate or fall out on it's own?
Old 11-06-06, 02:23 PM
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Rotaries confuse me

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Paper clip.
Old 11-06-06, 02:39 PM
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I figured as much :p
Old 11-06-06, 02:42 PM
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Originally Posted by Valkyrie
I figured as much :p
I suppose a small piece of wire would be better, but I just use a paper clip.
Old 11-06-06, 08:22 PM
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Huzzah! I reset the ECU (after spending maybe an hour just confirming that ALL of the wiring was ok, as well as the pressure sensor) and the code finally went away! This makes it seem as though the culprit was definitely the lack of the restrictor pill.

I guess I'll go to the Mazda dealer as soon as possible and get the pill (get the pill...lol).

I think the reason the code never went away is because I had just disconnected the negative terminal and didn't try to put a drain on the battery (ie, by stepping on the brake pedal, which seems to work, although it sort of defies all electrical logic) in order to somehow drain the ECU's power...or something.

I'm sure it'll come back on as soon as I go past that throttle amount (which I figure is a combination of the lack of the restriction and the colder weather, this is my first winter driving the RX-7...), but at least now I don't have to....*shivvers in fear* repair the harness... or buy any parts...

Seeing as how the restrictor pill has about a .5 mm orifice in it, it's safe to assume my zipties will have little or no effect on it.

As always, code 30 still refuses to go away, despite the fact that it's got proper voltage (although the voltage doesn't go down in 5th gear like it should). The solenoid itself also works.

Last edited by Valkyrie; 11-06-06 at 08:28 PM.
Old 11-07-06, 12:28 AM
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hey, how do you check codes on your car?? all the auto parts stores around here say there is no way to check codes... what are you using to check the codes???
Old 11-07-06, 03:23 AM
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S4 error codes: http://www.teamfc3s.org/info/article...odes/main.html
S5 error codes: http://www.johnr.com/cpucodes.html
Old 11-07-06, 04:29 AM
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Originally Posted by NZConvertible
You've been full of helpful links lately.
Old 11-07-06, 01:09 PM
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I ordered the orifice...it'll be here tomorrow morning.

I think this might also fix my annoying exhaust popping as well?
Old 11-07-06, 03:05 PM
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So the restrictor pill....
Has anyone done back to back tests to see the difference?

I get a terrible hesitation at the injector switch and I've never ran the pill. I'm wondering if installing one would help reduce the bucking I'm getting from that(yes Imy tps is set correctly).
Old 11-07-06, 05:28 PM
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There are multiple causes for the hesitation...

One, the secondary injectors might not be running. if this is the case you'll probably see it in the ECU codes. Or they might just be bad if it's not a wiring problem.

Two, the grounding for the pressure sensor (only on S4s... it's not a problem on S5s).

Three, grounds in general... clean/repair the stock ones and then add some if the problem persists.

I think not having the pill gives me SOME hesitations but it's not the 3800 RPM hesitation (although I haven't even tried going to full acceleration, throttle AND RPM-wise while I've had this problem... so I could for all I know). It's more of an erratic jump of RPMs due to any sudden throttle movement.

I may yet have some vacuum leaks, although the fairly incompetent guys at the Mazda dealer said they couldn't detect any (although they don't even bother to use a compressor or a fog machine... there are places where a stethoscope would NEVER find vacuum leaks, like the lower intake manifold gasket...
Old 11-08-06, 02:13 PM
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Battlefrak Fraktactica.

I dropped the pill... immediately after it came out of the package. After concentrating SOOO hard on not dropping it.

I guess I shouldn't have opened it over the engine bay to begin with... well, that's 4.5 dollars down the drain (2 dollars extra to overnight it).

I made a ghetto version of it with the applicator of a thing of superglue (which is basically the perfect size) and the problem still didn't go away, so I think the vacuum leak might be the original cause of the problem all together.

I fiddled with the brake booster hose (the one I replaced) that I had been suspecting for weeks and suddenly the idle dropped again... I think I found my leak :p The hose I bought was a bit too short and the clamps were too big for this hose, so hopefully everything will be honky-dory after I get a longer hose and better clamps.

...hopefully there's not a worse leak after I fix this one (namely the LIM gasket I didn't replace)...
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