The title mainly is the question.

 

I didn't know you could start an ECU, let alone restart one. Could you eleborate on what you are trying to do?

 

I just wanted to know if you can restart it. Ummm i'm testing everything today so i can get all my sensors out of the way.

 

yes the ecu normally restarts when you disconnect the battery for like 45 seconds and then reconnect it when you reconnect it it goes through a sort of reprogramming to everything the engine is running like more air flow so it adjusts your air to fuel and such and such

 

What do you mean by restart? That makes no sense when talking about the ECU.

 

No you can't. Not on an RX-7 stock computer.

 

OH ok then thanks ummmm just wanted to know. Since we just mentioned air to fuel how can i adjust that. I think half the time i am running way to rich.

 

I think what rotaries for life said is true of much newer cars, but not for rx-7's.
You probably are running rich, but thats how they are programmed from the factory. The only way to adjust the a/f ratio is to get a piggyback fuel computer like the SAFC-II or to get a standalone like a megasquirt or haltech.
There could also be something thats wrong with the car. What are the symptoms that make you think its running rich?

 

I added a fuel pressure regulator and gauge. Just did it this AM, adjusted the pressure which changed the A/F, you need to this on a dyno though. . Very similar to this setup: http://www.flatout-motorsports.com/c...roducts_id/147

 

as with any electronic component it CAN BE RE-SET. unplug the battery overnight and it should reset itself. ( it's supposed to work after 15 minutes but do it overnight anyways)

in order to mess with the A/F ratio you will need either a piggy-back or replacement ECU ( SAFCI/II $200-$1200 standalone) and a wideband Oxygen sensor ($200-$600)


NZ can you mess with A/F ratios on a stock car?? i was under the impression that the BAC screw was the rich/lean mixuture at idle but i'm sure it's not the same as TUNING anything.

 

you guys are thinking about a modern ECU which has fuel trim levels and stored error codes. an FC has neither, so disconnecting the battery probably doesn't do a whole lot

 

Reset my royal ***. BS

 

Ah, RESET the ECU. Very different to restart. It always helps to use the right terminology. Avoids confusion...

The BAC valve screw changes the idle speed by changing the amount of air entering the engine, and that air has been metered so there's no effect on AFR. The variable resistor on S4's can adjust idle mixture.

 

I'm assuming this would get rid of the stored codes on an S5, correct?

 

It's a series four *Dumb as a rock...never could learn......don't wanna learn* ECU.

The thread should have asked/stated what the engine problem is/was in my humble opinion.

 

Ok, S4 ECU is a red-headed stepchild, check.

S5 does store codes (which can be removed by unhooking the battery for a while)?

 

correct me if im wrong ( i usually am ), but doesnt the s4 ECU only learn per drive cycle? meaning it adjusts itself as your driving but when you shut it off it resets?

 

The S4 ECU doesn't learn.

 

Nope, S4 ECUs dont LEARN, they dont RESET, and they dont do stupid pet tricks. You unplug your ECU for 24 hours, and the one you plug back in is the SAME one you just unplugged.. Even with the same map!

 

Don't misunderstand us. We understand what your talking about, BUT, the 1987 series four ECU is *Dumb as a rock, ain't a gonna learn, don't wanna learn nothing*.

Your talking about MODERN computers that learn from a driving cycle. You'll have to ask the Rodent about those old series four computers and how life was waaaay back then. humor

 

Somebody answer my S5 question. I know it's an inferior model and I don't own one, but I'm just curious for some reason.

 

Inferior SUUUURE lol. Yes it does store codes which can be deleted via disconnecting the battery.

 

Thanks. And yes, they're inferior.

 

Did you read the section on the Self-Diagnonsis function in the FSM fuel Systems chapter? (Does anybody?)

"After-repair procedure: Cancel the memory of malfunction code numbers by disconnecting the negative battery cable for at least 5 seconds, then reconnect the negative battery cable."

A tool-free method of achieving the same result is to pull out the BTN fuse, which provides the ECU's constant power.

 

even then, I don't think the s5 ECU builds fuel trim (longer term corrective factors to the mixture that a modern ECU uses)