SAFC II problem, need help
 

my car starts then dies 2 seconds later. i gotta 89 TII and i finally came to the conclusion that it has to be the SAFC II, i if i unplug the safc from the ecu, it will idle but the injectors are wide open and they car is pretty much running with no fuel managment. any one know why the SAFC would do this? do you think it needs to be replaced? this problem is getting rediculous i cannont figure it out at all. but i know it has something to do with the SAFC. any advice would help ALOT, thanks

Sounds like... a vaccum leak... but then, it runs with it off? Perhaps you are not feeding it enough fuel and it just shuts off on it's own, when the SAFC is plugged in? Hmm, need the more knoledgeable people on this one.

How are you disconnecting it from the harness? I don't know how the S5s act but if you disconnect the SAFC from the harness without jumping the AFM IN and OUT wires in a S4, the engine will run stupidly rich and will just barely run.

Do you have the SAFC set up and wired right? Check in the SAFC section where this thread should be and you will find a thread where you will find a wiring manual I uploaded.

Flap, 06 06 TPS arrow up-right?

Did you just install the SAFC? It sounds like you didn't cut one of the wires to the harness like you're supposed to.

the thing is the safc was installed when i had bought the car. ive been driving it for over a year and one day i was just sittin at a red light and it stalled, never to start again. yeah, when i unplug the connector that connects the safc to the ecu, it will run really really bad, yeah, it runs super rich. the flap is 01 01 upper-right. but i believe its always been this way. but maybe it got changed? could that be the problem that its set to 01 01?, its at the shop right now cuz i coudlent figure it out at all, but i doubt there gonna be able to fix it if so happen it is the safc doing this. and another thing, i have an aftermarket ingniton and the main coil was also not firing, but when i bypassed the aftermarket ignition then the main coil started working. could this also be something with the safc? who ever installed the safc was a complete moron and spliced the wires really bad. should i put everything back to stock? or is that not worth it?

I would redo the wiring. Solder and heat shrink the connections.

The SAFC will not effect the ignition directly.

On my S4, I could have the AFM set to 01 01 or 09 09 and it would run OK for the most part. S5s may act a little different. The reason it acts like crap after unplugging the SAFC from the harness is because of the AFM output wire from the AFM to the input on ECU is not getting jumpered or connected back to the ECU so it has no signal at all and defaults. It should be 06 06, but this wouldn't cause your engine to die, or atleast, shouldn't.

Are you sure you don't have a large vacuum leak some where? Check your intercoolor piping. Having the engine die out when nothing was changed in the SAFC, and having the engine run with the SAFC unplugged having the engine run horribly rich, I could only assume that you have a very large vacuum or metered air leak some where.

Can you rev the engine at all when you have the SAFC unplugged? Mine I could not get past 1500 rpm.

With the SAFC hooked up, you can try adding a bunch of fuel in the correction map during LO throttle from 1000-1500 to see if it idles. If it does and does not idle "high" then it may be a leak after the AFM and before the TB. If it idles high, then it may be a leak AFTER the TB.

I can't help ya with the aftermarket ignition. You may want to find out what brand and model of the aftermarket ignition and look for a wiring diagram to see if its wired correctly. Possibly post the diagram up on the forum and someone could tell you which wire goes where. Shouldn't be to hard to tell. Following wiring diagrams are easy stuff.


Just in case you couldn't find the wiring manual, here is the one I uploaded.
http://midnightgray.net/docs/safcwiring.pdf

yeah, i cannot get the car to start at all with the safc connected. ill post the wiring diagram as soon as i can. i have checked every possible place there could be a vaccum leak, and found nothing. i really think im just gonna put the ecu back to stock. then go from there. this is really giving me a headache. i cant believe i cannot figure this out. do you think a messed up alam system could be the cause of all these problems? the guy at the shop told me that my alarm system what cutting the fuel before i found out that if i unplugged the safc that i could get it to idle crappy. and as far as reving it goes, it almost dies as soon as the rpms start to move, so nope, no good there

The only wire you need to disconnect from the SAFC is the Green AFM signal wire that is connected to the Yellow and White wires on the SAFC harness. You need to connect the two ends of the Green wire together. This will allow the engine to run without the SAFC input.

The rest of the wires are for monitoring and do no effect the engines performance unless the connections are horrible or wired incorrectly.

:wallbash: awesome, thanks alot for lettin me know i can just do that to bypass it. the safc has got me confused as hell. i kinda wish i would have installed it myself and learned how to operate it along the way. i wish i had someone to go through it with me once i get the car running again because ive read the instructions so many times, but yet it still seems to make no sense to me. i cant figure out why that with the safc connected it will not run, but if i unplug it, it will run horribly. i mean, how this problem started kinda makes no sense to me. i dont know how it could just be running and driving fine, and then i stop and idle, and then i touched the throttle and it lost rpm's and almost stalled, then i touched it again and it stalled never to start up again. i just dont see how the safc would have anything to do with that. i dont understand how anything would allow it to do that. when i was sick of trying to figure it out, i took it to the shop, and they first told me that my aftermarket alarm system was shutting off my fuel and that it should be removed. Next he told me the aftermarket ignition box was causing the main coil to not spark, then he told me it was all to do with the safc. the only place i know of in michigan that works on and installs aftermarket stuff was the Tuning Factory and i think they got busted for something. phone number dont work, i sent them an email on their page that says "under construction", and i got an email back with their phone number. so i call them, and it comes up "6th District" on the caller id, and they were asking me what i needed and stuff, once they found out that i just wanted my car worked on, the guy got all sketchy and was like, "OH, well we dont do that stuff" and hung up, so im assuming that was a cop on the phone considering the caller id name, they must have got busted for doing some crazy illegal shit for the 5-0's to be monitoring their phone calls. but anyways. this problem is killing me, i just wanna drive my baby before winter. what do you think the best thing to do at this point is? disconnect those wires and bypass the safc? take out the aftermarket Jacobs ignition. i know im gonna get someone who can take out alarms to take my viper alarm out that never worked for me. im sure thats not doing any good. id do it but ive heard to many stories of people messin with them and then their car not starting. i try to stay away from electrical stuff, becuse i definitly do not have the patience to mess with it. so where do you think i should go from here? im gonna keep the safc cuz you told me how to bypass it for now. but what do you think about the jacobs box, should i take it out? and then just reinstall everything after i get it running properly? because right now im just annoyed with the whole thing. im greatful for the info on how to bypass the safc, because i really dident wanna uninstall it. but as far as the af ignition goes, another thing that was previously installed before i got it, should i get a wire diagram and make sure its connected correctly, or just uninstalled it. damn! the thing is how could this stuff be the reason my car died and wont start, it was running perfectly before. i mean besides a ground wire or a short circuit somewhere. what do ya think i should do. sorry for me rambling on man, im just so tired of worrying about it. ive been driving a 2003 explorer, so im sure you can understand what i mean, haha. thanks for your help man, lemme know what you think i should do. your alot more knowledgable than anyone i know. so your advice is greatly appreciated. thanks alot man. ill be waitin to hear from ya. :Wconfused :Wconfused :Wconfused

Assuming it is hooked up correctly if the SAFC settings are all 0 on high and low then it is not doing anything. Try starting from there to get it to run. Do you have a wideband and is this a turbo? Thanks

89 T2, first post :)

How were you checking for spark?

Was the trailing coil firing when the leading coil wasn't? The engine should still start with only the trailing. I suppose this is depending on how the overall condition of the engine is. The combustion timing would be very retard if this was the case. Since the trailing fires late.

For the SAFC to gets its signals to operate correctly It needs the following

Ignition Power
Ground (2 grounding points for the SAFC)
RPM
Air Flow
Throttle Position

Since you have a T2 it should have knocking setup as well but its not needed for the engine to run.

Are the fuel injectors really NOT firing? You can hook up a LED from radio shack to each injector pin at the ECU. Use the manual I linked to on page 8 to find out which pin is which.

Pins;
3W - Primary Front Injector
3Y- Primary Rear Injector

You can hook the red wire from pre-assembled LEDs to one of the primary injector pins and it should blink if its working.

HAILERS gives a lot of good information about the working electronics of the engine and could possible help better then I could. Possibly try PM'ing him.

Here is thread with some good info from him about the ignition
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/only-one-spark-696458/

Is the CEL coming on at all?

Connect the 2 green halfs of the AFM output wire together and try to start the car and then gives us an update .

Have you figured out the problem?