3sgte Running Reallly rich!, any suggestions? Options

[eggman40]

I have a second Gen 3sgte, still running the top mount, stock injectors, 3in dp and 3in mandrel exhaust.

the car will backfire on occasion, you could sometimes smell the unburnt fuel and my air fuel gauge reads well into the rich area. Any suggestions? thanks

[BBoYRuGGeD]

u have a wideband o2 sensor w/ gauge? cuz the 1v a/f gauges dont really tell you crap...i dont even pay attention to mine. backfire as in spitting out some flames?

bboy

[WannabeGT4]

bad coolant temp sensor/bad coolant temp sensor for cold start injector, sticking/leaking injectors, bad throttle position sensor, bad AFM, bad fuel pressure regulator, return line from FPR to tank blocked, timing/ignition.

I'm sure I'm missing something but I'd check the cheap/free stuff on that list first.

Has it always run like this or is this a new problem.
Does this happen at idle or all the time?
Besides running rich how does the car run?

[presure2]

the factory ECU on the 3s is made to run rich especially in the higher rpms from the factory, its totally normal.
bboy is right about the a/f gauge, if its not a wideband, its just a light show.

[WannabeGT4]

Running rich to the point of backfire though? I didn't think it ran THAT rich. However, I guess if you're not running any cats it's quite possible that it would backfire and the smell of gas would definately be more apparent.

Oh yeah eggman, did you ever fix your high idle problem? If not I'm leaning towards coolant temp sensor.

[Chanh55]

Hey Egg,

I can refer you to a Dynotuner in my area, all he does is swaps and Dynotunes on JDM motors including Skyline motors.

You got my number, hit me up anytime.

Chanh

[eggman40]

u have a wideband o2 sensor w/ gauge? cuz the 1v a/f gauges dont really tell you crap...i dont even pay attention to mine. backfire as in spitting out some flames?

bboy

wow thanks for the resposes everyone. I guess ill start with, no im not running a wideband sensor, so i guess all i have is a lightshow, second there are no flames, just the occasional pop when i let off the gas. This is sort of a new problem. When i first got the motor running, the gauge said i was barely running rich but now it shows more gas going in. I never really fixed the idle problem, i did mess with the valve on the throttle body which helped just a little..... Is there a way to check the coolant light? AFM is good becuase we used it for Chan's motor and his ran perfectly with it. But i guess ill go down the list and see what turns up. thanks again guys for the help. i appriciate it.

[lagos]

that gauge is good for one thing.. telling you if your o2 sensor is working correctly. at warm idle, or at a cruise, it should bounce around from lean to ritch. if it dosnt do this, and just reads ritch or lean then your problem is with the o2 sensor. replacing it with a new one would fix it.

[burneeed]

that gauge is really just another pretty light...

[eggman40]

that gauge is good for one thing.. telling you if your o2 sensor is working correctly. at warm idle, or at a cruise, it should bounce around from lean to ritch. if it dosnt do this, and just reads ritch or lean then your problem is with the o2 sensor. replacing it with a new one would fix it.

thats good to know, the gauge does bouce around at idle and at a cruise so the sensor is fine

[jgreening]

The ST185 engines did not come from the factory with a BPV. Yours doesn't have an aftermarket BOV installed does it? Running these vented to the atmosphere will routinely cause backfires.

[Defgeph]

Do you have your fuel pump relay wired in ? If not that will cause the car to back fire. Your most likely getting 100% of fuel all the time.

I have a turbo back 3 inch with no restrictions. I only get small pops that I can barely hear.

[WannabeGT4]

You mean ST185 fuel pump resistor and relay right?

[Defgeph]

You mean ST185 fuel pump resistor and relay right?

Right, I didnt know I had to specifiy it. But thats the reason, for all the fuel.

Also make sure the O2 sensor is hooked up properly.

[DG_Performance]

Egg, why did you not tell people what you did to cause the rich condition. You did cause your own problem... you messed with the screw on the maf sensor and that is what is messing you up! Put it back to where it was and your problem will go away. You got more problems than any other swapper i have ever read about. HAHA

[lagos]

Egg, why did you not tell people what you did to cause the rich condition. You did cause your own problem... you messed with the screw on the maf sensor and that is what is messing you up! Put it back to where it was and your problem will go away. You got more problems than any other swapper i have ever read about. HAHA

BUSTED!

[WannabeGT4]

Egghead... I thought you said your AFM was fine. What's the deal man?

[bufferdan]

3sgte will run very rich in stock form. With aftermarket exhaust and downpipes you will get a back fire every now and then...with a BOV it will happen even more often. Its pretty normal and nothing to really worry about.

[scothaniel]

The 1v a/f gauges are not all that bad. Sure your not getting the full spectrum and they are not nearly as accurate for tuning a piggyback / standalone system. But if your running the factory ECU, then you are seeing the exact same signal the ECU is getting.

[eggman40]

3sgte will run very rich in stock form. With aftermarket exhaust and downpipes you will get a back fire every now and then...with a BOV it will happen even more often. Its pretty normal and nothing to really worry about.

thanks man thats useful info. i appricieate it .