Running rich?

[sjbsuperman1425]

ok, im just a little confused, and probably buzzed from some exhaust fumes since im running half an exhaust lol im still running full rich on my "narrowband" a/f ratio gauge when WOT, which is NOT a bad thing, rather have it to rich than to lean..cruising along at 2500rpm or below, its stoich, but towards the rich side of things

i have a walbro 255, NISMO FPR set at 36psi, and just changed the spark plugs to NGK BCPR6E-11 gaped at 1.0mm...what else could be causing me to run rich? maybe weak coils or ignitor or the O2 sensor going bad? thanks guys. im not uber worried about it, but its just bugging me lol

also, i have a basic "T" in between my turbo and the wastegate w/ a hole drilled in it. it will hit 11psi then drop to 7psi..is this because of the whole, and can i run a basic "T" w/o a hole drilled to boost 11psi? im just curious on this, its fun as hell with 7psi lol

[Ca_Silvia]

Before you mess around with boost, buy a real AF gauge. Those narrowband ones are garbage. Check out Zilvia advertiser section usually around 250 shipped.

[sjbsuperman1425]

Before you mess around with boost, buy a real AF gauge. Those narrowband ones are garbage. Check out Zilvia advertiser section usually around 250 shipped.

yea i know the narrowbands are not accurate but they are BETTER THAN NOTHING, and for being in college and still have an outstanding tool list to aquire, it'll do for now. all im asking with the boost is if it is fine to run a line straight to the wastegate from the turbo, since i cannot afford a boost controller.

[sjbsuperman1425]

anybody?

my engine is all stock, except for exhaust. i think im going to go get a new O2 sensor and go from there, as i unplugged all my coils and they are all working..

[zero_gripS13]

please dont pay attention to your light show...

get a jaw wideband if anyhting its like 150$ shiped.. after getting a sensor and s***..

that thing will not tell u anything important.... it could say rich but ur running stoich it could say stoich but ur running rich and what not... take it to a dyno and pay 100$ for 3 passes and they tell u what ur a/f are.

[sjbsuperman1425]

please dont pay attention to your light show...

get a jaw wideband if anyhting its like 150$ shiped.. after getting a sensor and s***..

that thing will not tell u anything important.... it could say rich but ur running stoich it could say stoich but ur running rich and what not... take it to a dyno and pay 100$ for 3 passes and they tell u what ur a/f are.

well its not a dancing light like the Faze gauges, but ok, and im not relying on it to tell me if im running rich.

to the point, im running rich. coils, ignitor, dropping resistor, new plugs, all good. walbro and nismo fpr set at 36psi, all stock motor. what else could it be besides the O2?

[zero_gripS13]

coolant temp sensoro2 sensordirty maf ensortps sensor

all have a impact on a/f ratio?

how do u know your running rich? what symtoms are u experiencing...

[sjbsuperman1425]

smell, backfire, bad gas mileage, and black smoke in exhaust.

would the temp sensor show any signs on the cluster? O2 sensor was ran on VERY rich conditions w/ walbro w/o a fpri think i have MAF cleaner somewherei'll look in FSM for TPS and also for coolant temp. sensor.

[sjbsuperman1425]

ok something new..i took off the downpipe to get it bend to put my catback on..i took it off and there is black carbon, but it also looks a little moist, like water is in there too..i can't tell if im "missing" any coolant or not..there is no coolant in the oil and no white smoke like there is coolant..if the turbo was leaking, it would burn correct?

could the "condensation" i see just be from running so rich also?

[Ca_Silvia]

Thats just condensation, and the soot is normal for rich conditions.

o2 could definatly be it, if you ran rich for a long period of time. ie DD for a year.

[sjbsuperman1425]

Thats just condensation, and the soot is normal for rich conditions.

o2 could definatly be it, if you ran rich for a long period of time. ie DD for a year.

the O2 on the car now is the one that came with the motor when i swapped it, plus i ran it without the adjustable FPR, so i think its toast, along with a set of spark plugs. i also adjusted the FPR to 36psi without the engine running. with the engine running its hovering around 25psi..is that correct? i'll replace the O2 and the plugs again and see how it is.

[sjbsuperman1425]

well heres whats going on..

replaced the O2 sensor, plugs, and put on a new coupler for the pipe-throttle body and it was running awesome. Didn't smell, was pulling 19"Hg., and boosted very well..but before coming on to boost, in like 2nd gear, it "bucked" a once then started boosting fine..it only did it once or twice..

but i also found my radiator hose was loose and leaking coolant, and my temp gauge NEVER goes over half anymore even if i leave the fan off the whole time i drive (aftermarket radiator and fan)..my air cleaner was also in a bad spot with low air flow, so i'll be moving that too as the FSM states that a clogged filter can cause a rich condition.

is the temp gauge a sign of the sensor going bad or am i just cooling it very efficiently? and could the air cleaning being in a bad spot cause a rich condition? im going to move the air cleaner and drive it for a bit, then check for codes and report back..might be a few days as i have to replace my calipers again..any ideas people? thanks.

[sjbsuperman1425]

sorry, ran this thread into my "idle hunt" thread.

Mode III pulled code 55 twice, O2 is new, plugs are newer, no vac/boost leaks, injector resistance are 3 ohms across the board. im thinking i need to possibly clean the MAF, or maybe adjust the idle mixture? Could my timing being off cause this as well? what about a bad ground? the ignitor and dropping resistor are both grounded. no exhaust leaks before the O2 sensor either.

[sjbsuperman1425]

another thing, the fuel pressure at idle should be at no more than 28psi correct? i have it set at that as thats what it says in the FSM. my other concern is the plugs. the exhaust says rich, and i think the plugs say rich and lean? here a link to the way my plugs look.

zer...13014

i feel like im close to figure this out..

[m_wolfenden]

those plugs are running mega-lean man

[sjbsuperman1425]

those plugs are running mega-lean man

its a crappy pic. it looks like its all white on top buts its only on the very tippy top of the "arc" that is whitish in color, the rest of it is the arc is the aluminum color, then the soot on the rest.

a few other things. im checking timing sometime this week. could the idle switch cause running rich and rough/hunting idle? these are the last two things i have it down too. once again fuel pressure is at 28psi at idle/ 36psi with engine off fuel pump always on. Thanks guys.

[alms24sebring]

what is code 55, pretty sure that hole in the intercooler pipe isnt helping, a coolant leak is ganna cause overheating, fuel pressure sounds low but might be right.. and finally no exhaust is ganna stink

[sjbsuperman1425]

unhooked the MAF and it idle perfect. removed sensor, cleaned it with MAF cleaner, reinstalled and had the "LIMP MODE" problem (ie wont rev past 2100rpm. im unhooking the battery and then connecting it again to see if it fixes it. MAF was pretty dirty though..

[busteds13]

Get rid of that T in the turbo line/wastegate actuator vaccum line, straight hose tops the turbo out at 7 psi also, according to other threads on the fuel pressure issues, you should have 36.6 psi with the pump on and the motor not running, and over 40 with the ignition on, cus turning on the ignition send vaccum to the fuel pressure regulator opening it up and allowing more fuel, put a guege on it, Before the rail , or before the regulator, i cant recall correctly but it might be about 44 or so ( psi at idle) dropping to 28 is odd? your setup might be a wee bit off, nismo FPR FTW!

[progman]

The static fuel pressure with no manifold reference should be 36.6 psi yes.

While the car is running the fuel pressure should be 36.6 + manifold pressure. This is so the vacuum or boost in the engine does not effect the fuel delivery.

36.6 psi of fuel at an injector that is injecting fuel into a intake port under 15 psi of boost (pressure) is the same as 36.6psi-15psi of fuel pressure. Now the computer is putting less fuel in than it thinks!!! Sure if the computer knew that there is 15 psi of pressure it could be possible recalculate the pulse width to get all the fuel in it needs but there is a limited amount of time to do the injection especially at high engine speed. But engineers back in day day had a good idea to reference the manifold pressure so at any time the amount of fuel the injectors inject would remain constant no matter what the pressure was at the manifold. plus if your fuel pressure is 36.6psi and your running 40 pounds of boost you would have a problem with the computer hackery. oh, and back in the day they didn't have computers...

If you have negative 10psi (psi used here just to simplify things) in your manifold when that injector valve opens it will suck with -10psi and the fuel will push with it's pressure at the same time and you will end up with more fuel. and as the manifold pressure changes the amount of fuel would change too. It would be a mess.

SO, at idle the fuel pressure regulator will LOWER the fuel pressure in the rail so the vacuum in the manifold can help suck in the right amount of fuel (36.6psi) vacuum + fuel rail pressure.

so 28psi in the rail at idle sounds correct. The fuel pressure regulator will only raise fuel pressure when your car is in boost.

your problem with the car running rich is really a pain in the a** with the old factory computer. It's really hard to tell if everything is working right with the ECU.

First if you have code 55 you can be mostly sure all the main sensors are connected properly. They can of course still be worn out, dirty or broken. To test the o2 sensor output you have to put your ECU is the special test o2 sensor mode and count the lights etc etc. see FSM

If all your sensors check out and the o2 sensor is working and getting it's signal to the car they are still be not working properly. for example, if the temp sensor is erroneously reading a low temperature your ECU will be stuck in cold start enrichment and it will run richer than is should. the FSM will guide you through testing most all the sensors. With the MAF the best thing to do it test with a know good one.

If your timing if off it could also cause your car to run rich/lean. Check this with a timing gun. You can also check your belt and count the teeth to make sure it is correct. It's good to check this anyways.

I would then next pressure test your intake from the filter back. Put about 5psi in and listen for leaks.

checking your grounds with a multimeter is a good idea too.

If you have the stock MAF and it's on the stock intake pipe in the stock location you should be good at this point. but if you have changed anything here you can really screw up the MAF readings. If your MAF is near a pipe bend higher velocity air could be sneaking around the other side of the MAF. Also things could be causing turbulence and you would get faulty readings as well.

That hole in the Tee for you waste gate signal would cause air to leak from the air system unbeknown to your computer. That would cause it to run more richly but probably not enough to cause any type of problem.

Also, narrow band o2 sensors are extremely accurate. but only at stoich. If you are cruising around at stoich then I would think your o2 sensor is working perfect. But when you cruising you should be in closed loop mode. in closed loop the computer is ignoring the sensors are just going off the o2 sensor. It does this for idle as well. during cold start it is normal for the car to run rich. Do you see black smoke at idle with the car warmed up fully?

Also, the thermostat should keep your temperature about the same no matter what radiator you have. If your coolant is a little cooler than before it may make a negligible impact on A/F ratio. and the temp gauge in you cluster is read from a separate sensor than the one your computer reads from. so it's not helpful for this issue. It's just there to alert you if you're over heating or still warming up.

How did you clean the MAF sensor? It should have worked after you reinstalled it. no reason for it not to. I have plugged and unplugged a MAF on a running CA many times before. Perhaps its was problematic and it finally died?

If you still can't fix it then the next thing you should be is commit murder-suicide cause this can be such a pain to track down.

[busteds13]

i stand corrected, mine is special and im not sure as to where i got 44 psi from my bad, but that t is prolly causing all sorts of issues.

[sjbsuperman1425]

i totally forgot about this when i encountered my MAF problem lol the car has been running fairly decent the past few weeks since i got my new MAF. i just pulled this thread up like 15 minutes ago and decided to go remove the "T" which was supposed to be a MBC that i messed up..

Results:-doesn't seem to hunt anymore, but will have to confirm over the next few days. -no more 11psi boost pike! the highest it goes is 9psi and then settles down at 7psi

I think that thing was the source of alot of problems lol. im going to have to get an oil catch can here pretty soon as im getting quite a bit of blow by. thanks again for everyone.

[sjbsuperman1425]

well its still rich..Code 55 in Mode IIINew stock MAFinjectors, ignitor, and Dropping Resistor tested goodcoil packs good.

i guess the only thing left is a boost/vac leak right?maybe a blown out gasket for the IACV?

[Ca_Silvia]

Time to make a tester!!

Quick question, do you zip tie all your vacuum connections? It helped me alot when i went through the whole boost leak issue.

[sjbsuperman1425]

no i dont but thats a good idea.

[Ca_Silvia]

Do it! I spent a week last fall boost leak testing and being real f***in anal about it. Changed out all those tension clamps(?) for worm gear clamps and zip tied every single vac hose connection. It helped me alot.

Also while im in a roll here, are you running all new vac hoses? If not replace with new s*** or cut of the ends so a "new end" is now sealing around whatever. Make sense?

[sjbsuperman1425]

well running rich is still a problem, but not a bad one. i did the zip tie thing and it made me feel better, but dont think it really did anything to help my situation. i also went out today and tested the TPS which is good.

i noticed the other day that my oil did smell like fuel (probably from when my MAF went out..) i still have good oil pressure at cold start, idle, hard pulls, but i think i may change it as its getting black..haven't checked the plugs yet but i should probably replace them. Its dumb because i get 19"Hg, but when shifting, i get blueish smoke, so i think im getting some blow by..but my car still runs like a champ and drives amazing..

also, whats a good way (besides pulling the fuel rail) to check for leaky injectors? the resistance in them was good a few months ago, but im just curious..i primed the lines and let it sit and am checking the pressure drop, but am unsure if this is an accurate way of testing..

Thanks..sorry for the LONG post lol

[sjbsuperman1425]

fuel pressure after about 10-20 minutes dropped ~8psi, but idk if this is an accurate way of testing fuel injector leakage.

these are basically the symtpoms im getting..http://www.youtube.com/watch?v=ZnvaQ3oa710

^^is that normal and im just being anal?

[sjbsuperman1425]

well i did the zip tie thing with the vacuum hoses and made sure they were all good and everything checked out..it did help a bit with the "dieseling" after shut down, but rich problem still persists..

im going to pull codes off the ecu again, just to be sure. but other than that im stumped? maybe one of the sensors is bad and just not registering on the ecu?

would an exhaust leak at the O2 housing/dump pipe cause a problem? i think i have one.

[sjbsuperman1425]

oh yea, and eventually i am going to get or make a new ground cable as i know grounding is a serious thing to do..where does the transmission ground too though? i didn't see a ground wire for it.