hooked my safc 2 up and got problems!

[riff22]

well i hooked my safc2 up to my car everything is still stock cuz im still waiting on my injectors, and some extra cash to get my regulator, but i set the th-points at 79 and 80 and i left all the ne points at 0 till i get all my stuff put on. well the car runs good till you hit higher rpms and it starts to cut out like miss or fuel cut, i dont know? so i unpluged it and it runs fine.. is there a reason or a fix? or am i just going to have to wait till i get everything installed before i plug it back in?
thanks

[spyderturbo007]

Set the low throttle to 30% and the hi throttle to 70%. Verify that you set the sensor to Karman. Make sure that you hooked it up properly. There are 2 major problems most people have with the install. Splicing the wrong wire for the MAS and hooking up the 2 grounds wrong. They must be hooked up according to the directions. One must be closer to the ECU than the other. You also don't want to do the "blue wire mod". What directions did you follow? These are just some general things to check.

[riff22]

umm.. its on karmen, i put the brown ground closer to the ecu, i used the karmen sensor hook up directions. its on 4cyl. with the arrow pointing up. ive read alot about tunning and install im still not fully understanding it.

[riff22]

what is the high and low do? there are so many diffent answers as what to set them too.. maybe i need to check the high ne's i didnt do them cuz when i went through the low ne's they were all set to 0 already, so i figured that it came factory set to 0

[spyderturbo007]

The high and low are the throttle points that determine what airflow map the SAFC uses. For example. If you set the low to 30% and the high to 70%, the AFC will use your low throttle tables at anything below 30% throttle and your high throttle tables at anything above 70%. In between (31% - 69%) the AFC will extrapolate the value. It is actually a weighted extrapolation, but that's for another discussion.

The Ne points are the rpm values assigned by you, the user. You can choose different rpm values based on where you want to be able to modify the airflow signal the ECU sees. Within these Ne points there are the two tables explained above. This allows the distinction between regular cruising and WOT.

Go here for tuning advice:

http://www.racingknowledge.org/topic.asp?TOPIC_ID=1011

Here for install instructions:

http://www.prostreetonline.com/pso/p...p?articleid=25

Let me know if you have any other questions

[riff22]

thanks, i have read both of those before.. i double checked last night all the wires are right, (pink and orange are together, and brown is ecu side) and the high and low ne points are set at 0, set on karmen, 4cyl. up arrow, what about the deca air?and the car still hesitates around 3,500-5,000 rpm, when its unpluged its fine. i dont get it??

[riff22]

i think i may have figured it out, i havent drove it yet cuz im at work, but the airflow wire on the ecu gets the pink and orange wire, well all the other wires you just t in but this one the pink gets one end and the orange gets the other end. get what im sayin? the airflow wire doesnt connect back to its self the wire is seperated to the pink and orange(with the pink closest to the ecu) i will post later on if this is a fix.
thanks for all the help!

[spyderturbo007]

Originally Posted by riff22

i think i may have figured it out, i havent drove it yet cuz im at work, but the airflow wire on the ecu gets the pink and orange wire, well all the other wires you just t in but this one the pink gets one end and the orange gets the other end. get what im sayin? the airflow wire doesnt connect back to its self the wire is seperated to the pink and orange(with the pink closest to the ecu) i will post later on if this is a fix.
thanks for all the help!

That would be the problem. You actually need to cut the airflow wire going to the ECU. One side is attached to one wire on the AFC and the other side is attached to another wire on the AFC.

In a nutshell, what you are doing is "grabbing" the airflow signal before it hits the ECU and sending it to the AFC. The AFC is then used to modify this signal and send it along to the ECU. If you just spliced into the wire you will definately have problems.

Good thing we had you check the wiring again!

[riff22]

yea, thanks spyderturbo, i will let you know if its a fix. oh and how do you the faces in the post? and post a pic?

[gthompson97]

faces are emoticons. when you're typing a message, click "go advanced" and you'll see them.

you post a picture in your signature in the "user cp" tab at the top of the page. there should be a little mountain looking button on the signature page, that's how you insert a picture. you'll probably have to host the picture first though through www.imageshack.us/

[riff22]

ok, thanks

[riff22]

finally, fixed the problem it was that wire, car doesnt cut out with the computer one! thanks guys!

[spyderturbo007]

Originally Posted by riff22

finally, fixed the problem it was that wire, car doesnt cut out with the computer one! thanks guys!

Now you just have to get it tuned.

[riff22]

yea, i leave it at 0 for stock right? i just ordered that regulator in that other post so i will be ready for the pump, reg, injectors, and turbo install soon! from what i understand this is how it works correct me if im wrong. when you turn the safc to a positive number at a certain rpm its tricking the computer, making it think more air so it adds fuel. and if you go neg. number it makes it think its getting less air so it takes fuel away?? so when i put my pump injectos and turbo on i will have to go neg number so it takes fuel away to compensate for the bigger pump and injectors, right?

[spyderturbo007]

Basically you are modifying the airflow that the ECU sees. So using a negative value will show the ECU a lower airflow so it won't open the injectors as long as it normally would. On the other hand, a positive value will show the ECU more airflow and the ECU will open the injectors longer to correspond with the increase in airflow. This is how you compensate for larger injectors. The ECU has no idea that you have changed injectors. It looks at airflow and then opens injectors for a specified amount of time based on that airflow (and other things). So when you get install bigger injectors the ECU will still open those injectors for the same amount of time as it would for 450cc injectors. This will cause more fuel to be injected and result in a rich condition. You will need to adjust the SAFC to compensate for the increased fuel. Standard correction for 550's is -18%. That is just a starting point, you will need to look at FT's, timing, etc and tweak that value.

Calculation (old injector size/new injector size) - 1

= (450/550)-1 = -18