Need Help...SR running abnormaly rich....

[Rosco]

So my SR's running so rich to the point i can see loads of black smoke out of the exhaust. It acts like a boost leak(i have no boost leak) until after 4kRPMS and then revs normal....Things I have done: ECU code check: Code 55 all clear Changed Z32 MAFS Ran B12 Chemtool through one tank of gas seemed to only work for 5 days Changed T-25 wastegate Checked grounds all good Plugs are fouled with carbon buildup (due to running rich, duh!) I do have a small exhaust leak (definately not the prob tho) SAFC was readin only 30% Airflow at 100% throttle I have 2 MINE'S tuned ECU's which I inspected for burns and there where none..... BOV is re-circulated....I took an OEM FPR off of my spare SR and still no change I will be checking Voltages today on the TPS, MAFS and whatever else I can.

The car had been running good for 2+plus years and this is the first "major" trouble I've had.....Any ideas??? OOPS wrong SR20DET Forum.....meant for RWD one...

[Wretched]

First thing I always do is get rid of that safc junk. But it sounds like you have a fuel injector stuck open or got some trash in one of them causing it to hang up.

[godofspeed666]

Things that can cause any vehicle to run rich.

maf sensor out of adjustment or worn out or slow.

Fouled plugs.

Low battery voltage.

low alternator voltage for every 1volt your low at your coil primary circuit you will be low 1000v at you secondary.

bad grounds high resistance.

No ground.

An exhaust leek before your 02 sensors or bad o2 maybe slow or off.

a leaking injector at injector pintle

if there was a leek at in the intake ducting after the maf sensor at idle or slightly off ideal then it would run lean. once you built up boost then you would be running Reich that including the intake manifold.

also malfunction ecu or needs to be reprogrammed.

Also you need to know when this problem started if it started after some modifications were made them chances are it was what ever was recently replaced.

also if you upgraded your injectors you could have gone to large

hope this helps you out if I think of any thing else I will let you know.

[godofspeed666]

O yea check you vacuum lines especially the one to you fuel pressure regulator.

Check fuel pressure at ideal and see if it’s in spec

[Justin35ll]

check injectors for leaks

[Kalypso]

Things that can cause any vehicle to run rich.

maf sensor out of adjustment or worn out or slow.

Fouled plugs.

Low battery voltage.

low alternator voltage for every 1volt your low at your coil primary circuit you will be low 1000v at you secondary.

bad grounds high resistance.

No ground.

An exhaust leek before your 02 sensors or bad o2 maybe slow or off.

a leaking injector at injector pintle

if there was a leek at in the intake ducting after the maf sensor at idle or slightly off ideal then it would run lean. once you built up boost then you would be running Reich that including the intake manifold.

also malfunction ecu or needs to be reprogrammed.

Also you need to know when this problem started if it started after some modifications were made them chances are it was what ever was recently replaced.

also if you upgraded your injectors you could have gone to large

hope this helps you out if I think of any thing else I will let you know.

good insight

[godofspeed666]

Also check coolant temp sensor and intake temp sensor. Colder engine or colder intake air needs more fuel then if it’s hot.

Also the problem with running to rich that it fouls the plugs out or a misfires that it creates an incomplete combustion not burning all the hydrocarbons and air. when this happens you have raw gas and air exiting the cylinder the o2 only look at the amount of oxygen leaving the exhaust not fuel and tries to keep it at close stoichiometric as possible which is 14.68:1 if there is raw gas and air reaching the o2 it only sees the oxygen and thinks its running lean and tries to throw more fuel at the cylinder until it max out the injectors.

This creates quite a conundrum

all that is left is to Divided and conquer.

[Rosco]

Thanks for the help guys but I never figured it out.....I ended up blowing the motor....Probably due to running so rich that the fuel mixed with the oil and made its way down to the bearings causing some serious rod knock.....I have a spare motor, but I have no idea if its any good...I'm probably gonna sell everything and go to WRX-land. Just really tired of wrenching on the car for the past 2 months and not getting anywhere....keep a look out for it in the classifieds....I got a s***-ton of extra parts...