First off I am one of the people who uses the search option alot more than posting problems. I currently just installed the 330cc injectors,sfmu, aem wideband, symtech fcd. The problem I am having is that my cars a/f while idling is around 15.2. I set the idle pressure to 20 psi on the sfmu w/ largest disk & dark spring. I checked the voltage on the fcd and it was at 4.50v. While the idle is at 15.2 and the car sputters, it is still drivable to some degree at least.

The other problem is that since I installed the injectors and other things. My turbo timer now likes to count up by itself when my car is just idling. Then when I go to turn the car off the car won't stay running while the turbo timer counts down. I just can't come up with a good reason with why my car is acting like this. The idle fp is set like it should be, but I don't get the a/f readings I should get and the idle is horrible(sputters, backfires when reving, and bogs when throttle is applied).

I checked the sfmu diaphram, all vaccum lines, all electrical connections and it all is good. The problems are just the idle & a/f readings and the turbo timer acting stupid. Could I have somehow got the wideband hooked up to a bad 12v switched source? But that wouldn't explain the bad idle with the injectors. I did have a safc hooked up but the unit is shot so I had to disconnect the wires I had soldered to the harness. Maybe that is my problem, hell I don't know. I know its alot of info but I tried to give as much info as I could so you all would have a better grasp of the situation. Any help would be great and like I said I used the search option and read through all the pages but nothing really helped. So any advice?

anyone????

is the stock ecu using a simulated signal from the wideband? or are you using the stock o2 sensor?

Because ive heard that our ecu's dont like the simulated narrowband signal

I have the stock o2 sensor still hooked up to the ecu. I just have the wideband o2 hooked up to the gauge.

What are your safc settings? I ask because you really dont need any correction at idle if you have the fuel pressure set correctly. Actually my idle on my car bounces between 14.7 and 15.2 and it runs fine, so your car sputtering at 15.2 is kinda confusing to me.

I had the safc hooked up, but it doesn't work at all so I took it out. I've tried my idle fuel pressure anywhere from 18-23psi and get the same a/f readings and same shitty idle. I even turned the fuel pressure up to the stock level of 48 psi and it still idled the same and the a/f readings were still right around 15.0. When the car first starts to idle the a/f readings are in the low 13's but slowly go up to around 15.0, and then even jumps back and forth from 15.0 to 17.0. I've looked at the fcd connections and they are good. I unplug the map sensor to see if it was bad and it was good, so I don't know. The car ran great up till I installed the 32lb injectors, sfmu, fcd, and wideband. I might put the stock injectors back in, but don't want to go through all the trouble if it isn't the problem. I know the sfmu isn't damaged b/c I have used it with dsm 450's before, and They idled fine below 20psi before. I checked all the connections where the safc was wired into and the connections seem to be fine. No vacuum leaks and my egt at idle are right between 800-900 degrees.

I had one of my O2 sensors go bad when i was running C16 and it caused my car to run lean. I dont really think that is your problem though if it was running fine up until you changed the injectors. Also when you say that the voltage on the fcd is 4.5 what do you mean exactly. Is it reading 4.5 when the car is not running or when it is at idle? It should only read read 4.5 when the car is on but not running. IF your fcd is working like i just said then i would try unplugging the front O2 sensor and see if it runs better.

Yeah it shows 4.5v when the key is on but not running. It might be the o2 sensor since I had to take it out to get the other bung welded on. To my knowledge it hasn't been changed in about 3 years/30,000+ miles and probably for alot longer than that. I got the injectors from another member on here and they were supposed to have been in great condition. I will go try to see if it runs any worse when I unplug the o2 sensor and post the results asap.

Just checked the front o2 sensor and I think that might be the culprit. I went out and cranked the car and when it first starts the idle is right around 13.2 or so and then leans out to around 15.1. When I would unhook the stock front o2 sensor the car would idle the exact same(no change). I checked to see if it was just not connected good and so I checked it again and the idle doesn't change. Before I buy another one though, do you think that's the problem also Travis? And where would the best place to get one from? I've read that the bosch from like autozone is not the best and to go with the mopar. If that is the problem then I need to get one asap, preferably from somewhere local.

The reason for the richer idling at startup is the fuel enrichment bacically the same thing as using a choke on a carberator(dont know the spelling). It sounds like your sensor isnt working right. But before you buy one, check a few more things. I dont know about Aem widebands but i know on my Innovative wideband i have to calibrate it regularly. If so, is your calibrated. Also do you have any CEL codes, before you unplugged the sensor. If so i would get the car to autozone and see what your ecu is saying before i spent 75 on a sensor.

I don't think the aem widebands have to be calibrated. I think the only thing you can calibrate on them is the switch on the back that either shows the lambda readings or the a/f readings. All the aem has is 2 harnesses the 1st one is hooked up to a switched 12v source and ground, and the second harness just connects to the end of the bosch uego sensor that comes with the aem wideband kit. I just have the aem showing me more precise a/f ratio's and the stock o2 is still running to the ecu as it always has been.

Got my friend to come over with a obd2 scanner and the one and only code it was throwing was for the map sensor; and that it wasn't working properly. Would the fcd being connected to the map sensor make it throw a code? Also my harness on the ecu has been molested several times from an safc being wired in and taking out. I will check those connections again to make sure if they are soldered good and also the fcd connections.

So this morning after searching and reading through some posts on here, I decided to take the fcd out. Once I got in out I tried letting it idle and it seemed like it wanted to idle back down around the low 13's, which is where it should be. But unless I get that code for the map sensor cleared the car won't run correctly right? I know its a dumb question but figured i would ask any ways.

Originally posted by BoostedEclipse
around the low 13's, which is where it should be.

Bear with me guys, cause I don't play with them there snaily engee-ins that much. But shouldn't that be right around stoich at idle (14.7ish)? Is there a reason that you want her in the low 13's?

Yeah, that is correct. I was going by what the guy I got the injectors from had it at with a rough tune. Which I know every car is different but it cycles from about 14.8 to over 18.0 and almost dies. Usually staying around low 15's to low 16's. The throttle response is shitty, all it does is stutters & backfires and the idle is really rough. The only code it was throwing was for the map sensor not functioning correctly. But it was working fine when I installed all that crap and still whenever I unplug the map sensor while idling the engine almost stalls. So idk????

If you unplug your map sensor the car should die. Also it shouldnt idle low 13's. Thats pretty rich at idle. 14.7 is what you should be aiming for.

Well I decided to just go ahead and put the stock injectors back in to see if it would idle better, and surprisingly it idles just like stock around 14.7-15.3 . I guess the stock feed line for the fuel just couldn't handle the lower pressure(which I know I should have upgraded first) that good or either one or more of the 32lb injectors was clogged or a pos. I'm leaning more towards the stock fuel feed line is the problem, since I knew I should have replaced that before installing larger injectors. Either way at least its drivable now.

Are you talking about the feed side of the fuel system or the return side. Actually i dont see why it would matter about the fuel line. If you have a given pressure on the high pressure side of the regulator changing the size of the line shouldnt matter. I would send the injectors to RC engineering and get them worked. Cost like 120 shipped when i did it and you get to see exactly what each injector is doing.

Yeah I probably going to do that, or just try my 450's on there again.

Originally posted by BoostedEclipse
Yeah I probably going to do that, or just try my 450's on there again.

Sounds more like a bad MAP causing fueling issues, and you're chasing your tail because you don't know if its the map affecting the fuel, or the fuel system, or the injectors you added, or the SFMU settings.

if you were getting a code for the map, verify the MAP sensor is doing what it's supposed to be doing. I've seen stock ECU controlled 2GNT's idle upwards of 17:1 and they feel stock - no sputter, stock-like throttle response, everything. I doubt your problem is the injectors, or *just* the injectors.

Your the man dino.

Hey BoostedEclipse,

Did you remove the wiring for the SAFC from the actual wiring harness to the ECU and reconnect the wires appropriately? Be sure to remove the SAFC wiring and reconnect the wires appropriately. A couple of those wires splice into a wire and loops through the SAFC unit. If the unit is off, the connection is broken and your car wont run right at all.

Yes, unfortunately im talking from experience. I have a 95 and was getting the CEL 14 - I decided to ditch the SAFC but didnt remove the wiring. The car didnt run right at all, and once I removed the SAFC wiring it ran great