AFR's driving me nutzzz!!

[Josho]

I'm in serious need of help! I can't figure out why my afr gauge is constantly reading 10.0!! Details- s13 blacktop, redtop wiring harness, all redtop sensors, cams, gt2871, 850cc inj., Nismo fpr, z32 mafs, fmic, I.H.E., enthalpy ecu. At fire up the afr(AEM wideband) starts around 14.5, it'll slide over to about 16ish and then slowly fall to 10.0. Regaurdless of where the fuel pressure is set, if I adjust the fp ithe afr will go up a little but falls right back down. My plugs are blackbut not soaked in fuel. blowing out black smoke of course. Some things I've also noticed.; AFR 10.0 idleing @900rpms, vac reading btween 6.5-6.9. Also, my temp hand NEVER reaches normal
Op temp. It'll get just above C and sit there.
Anyway, I can take offand my afr will bounce around 12ish but will fall right back to 10.0 after a few seconds. When I pull it out of gear after cruising, it will try to shut off on me until I rev it up a few Times.

[waxball88]

Pull your injectors i bet they are leaking.

[hardparkd]

Pull your injectors i bet they are leaking.

i got my money on the o-rings too. make sure you lube them up good so they dont tear. mine did the same thing but on my ka, had a nasty tear in the o-ring's. changed the orings, lubed them up really good. havent had a problem since

[Josho]

I've had this problem before. But it was leaking so bad that it was filling up the cylinder. Ill pull the rail off and check them out.

[Josho]

I pulledf the rail off, sure enough they're ALL leaking! Crazy thing is, I just reeplaced them 1000 miles ago(3 months ago). I have a pic that I'm going to upload to make sure the orings and plastic rings are in the proper spots.

[Josho]

http://i526.photobucket.com/albums/cc347/STM_Josho/Mobile%20Uploads/20120312183110-1.jpg

I have a feeling that the oring is suppose to go inbetween the plastic rings, but I'm not positive. Also, the rubber cap that goes over the injector covers, is the metal side suppose to touch the top of the injector or the bottom of the cover?

[Josho]

Any input?

[di-devol]

Are those the sard 850's? You have the collars on them right?

[Josho]

Jecs 850's

[Josho]

Well, I replaced all the injector orings. Still running aweful! I unplugged the maf and it ran the same but had a 2500rpm revlimiter and as soon as I plugged the maf back in, the car shut off. Plugs are black once again.

[di-devol]

Did you check for boost/vac leaks?

[Josho]

I have. Maybe not well enough though. I've just kinda searched around making sure everything was tight and without holes.

[steve shadows]

I'm in serious need of help! I can't figure out why my afr gauge is constantly reading 10.0!! Details- s13 blacktop, redtop wiring harness, all redtop sensors, cams, gt2871, 850cc inj., Nismo fpr, z32 mafs, fmic, I.H.E., enthalpy ecu. At fire up the afr(AEM wideband) starts around 14.5, it'll slide over to about 16ish and then slowly fall to 10.0. Regaurdless of where the fuel pressure is set, if I adjust the fp ithe afr will go up a little but falls right back down. My plugs are blackbut not soaked in fuel. blowing out black smoke of course. Some things I've also noticed.; AFR 10.0 idleing @900rpms, vac reading btween 6.5-6.9. Also, my temp hand NEVER reaches normal
Op temp. It'll get just above C and sit there.
Anyway, I can take offand my afr will bounce around 12ish but will fall right back to 10.0 after a few seconds. When I pull it out of gear after cruising, it will try to shut off on me until I rev it up a few Times.


Has it ever run this rich before? 850 cc injectors are bit large to run off the stock ECU. I always tell peeps that if they really need to be running more than 740cc injectors in the first place then they should be working with a more professional shop and a Haltech and real dyno tuning. Or at the very least build their own knowledge base to make the car run right themselves.

740CC injectors should be enough for 400-435 WHP no problem if tuned right.

But in the case that it is mechanical what is your fuel pressure?

If your base fuel pressure is jacked up then the mapping from Scott/Enthalpy will not be right. He usually sets it up for stock fuel pressure or around 38 PSI with the vacuum hooked up at idle max.

[Josho]

I have moved the fp all over. No matter where its at, it acts the same. The condition might ge a little more severe or a little less, but it doesn't stop smoking or reading in the 10's on the afr gauge.

[Josho]

Just pulled the fuel rail off, injectors are not leaking. I adjusted the TPS to .45v & cleaned off the spark plugs. Fired it up, afr gauges started at 14.5 but slowly fell to 10.0. At idle it bounces between 10.0-10.4. Pulled plugs, they're black again and the pistons are wet.

[Josho]

Ecu flashes once slow and 2 times fast.

[702s13]

did you check for boost leaks? is your bov getting stuck open maybe?

[Josho]

I do know that when I'm driving the car the bov isn't near as loud as it use to be.

[waste_of_space]

Bad MAF. Your code 12 confirms it.
Or double check your wiring.

[Josho]

Well I reground my maf and I did have a ic pipe that had popped out of a coupler. Got the ic pipe back in place And tightened it up real good and now my bov is going off again.... but now I have another problem. First, I can't get the afr where its suppose to be @ idle. The best I could get was 11.0-11.3.I decided to try and take it around the block and as soon as I'm fully off the clutch and moving, the afr shoots way over to lean. It starts at 17 and bounces between 15 and 16.5. So I pulled it in the garage and walked in the house. It sucks not having much time to work on this thing.

[Josho]

Well I reground my maf and I did have a ic pipe that had popped out of a coupler. Got the ic pipe back in place And tightened it up real good and now my bov is going off again.... but now I have another problem. First, I can't get the afr where its suppose to be @ idle. The best I could get was 11.0-11.3.I decided to try and take it around the block and as soon as I'm fully off the clutch and moving, the afr shoots way over to lean. It starts at 17 and bounces between 15 and 16.5. So I pulled it in the garage and walked in the house. It sucks not having much time to work on this thing.

Does anybody know what could be cause of my current problem?

[kouki_drifter]

hey man im having the same issue i got a 97 kouki with an s14 sr20det i just rebuilt
here is a link to my rebuild post

http://zilvia.net/f/chat/415523-s14-sr20det-rebuild.html

every thing was working fine, it currantly has 1300 mi and i installed the split fire coil pack set up, an aem tru boost gauge and a aem wide band eugo a/f ratio gauge
about a week and a 1/2 ago and about 5 days ago my car started doing the same shit yours is. out of no where it started running rich as hell bogging, smoking, dying the same shit at idle while driving it it was at about 12-13 but i would park it for about an hr and when i would start it it started going lean as hell out of no where 15-16 wtf! and it would change back and forth rich then to lean and now its just staying lean as hell 15-17. i checked! no vac leaks, no boost leaks, no exhaust leaks, and no fuel leaks! wtf i just checked compression today all cylinders are at close to 120 which is low i know but it idles fine and runs fine except for the a/f ratio issue. i checked the fuel pressure its at 42psi when the system is charged at the key on position, 42psi at idle, and 52psi at the highest i seen under a load "driving" at about 60-70mph in 4th gear i couldnt find any thing wrong that would cause this. i also put back my oem coil packs did the same shit! turned off the tru boost so it runs on waste gate spring pressure and still no change i dont know what else to check???

here is a link to my a/f ratio post : http://zilvia.net/f/s-chassis/442896-s14-sr20det-f-ratios-bipolar-help.html

[kouki_drifter]

you find a solution to your issue man?

[Josho]

Haven't had time to mess with it yet. I will later today. Mine us just like yours, started out of nowhere and nothing looks out of place. This sr has been the best one I've ever had, never had any problems even after the head was built. Until now.I'm wanting to take it on my vacation in 2 days, I'm not sure if that's going to happen or not. Pm me man, we can exchange numbers and try to figure this out.

[Jybfan04]

I would contact Scott and try to work with him to get an opinion of whats causing you run rich.

[Josho]

I got in touch with them. Seems they will be able to help. Ill keep this thread updated.

[kouki_drifter]

Just put the new engine harness no differance still hmmm, I was thinking if it could possibly be the coolant temp sensor? Is it used to give the ecu a temp reading so it can change the a/f ratio? Or could it be the mafs? And since there is gas in my oil could it possibly be that I have a leaky injector and it's leaking down into the crank case and the fumes are recirculating up top to the head through the Pcv valve or other hoses and making the o2 think it's running rich and that's why it's leaning? Does your oil smell like gas? Mine even burns a little bit when I put a lighter to the dip stick

[di-devol]

^swing and a miss.

[kouki_drifter]

^^^So your saying that none of theses things could be the reason for this issue?

[Josho]

I replaced the coolant temp sender and now my car is reaching full operating temp. Seems to be running a little better. At idle its still running rich. If I hit the trottle it will still stay around the rich side but as soon as the rpms start to drop down it goes all the way lean the back to rich once idle settles back.

[c-los13]

My car was running stupid rich and it was the bov sticking open. do a boost leak tezt and check for any exhaust leaks before the wideband that could cause to read wrong.

[di-devol]

^^^So your saying that none of theses things could be the reason for this issue?

Sorry, it looked like you posted something different than the op. Had nothing to do with your diagnostics.

[JKTUNING]

Do you have access to a consult cable so you can at least check over all of the sensor data that the ECU is seeing?

Just shooting in the dark like this can be a painful process without seeing any other relevant data on what the car is actually doing.

[Josho]

I sure don't. Will that work with a factory ecu?

[JKTUNING]

I sure don't. Will that work with a factory ecu?

Absolutely.

I have the ECUtalk USB consult cables on my site, PM me if this is something you might be interested in.

It will give you access to all of the main engine sensors to see if anything is out of range.

[s14k]

check to make sure your maf is working properly sounds like there is a weak or intermittent signal from your ecu. check to make sure u are recieving voltage to the maf.

[Kingtal0n]

I would do two things first before anything:

#1: Fill the intercooler plumbing with air by making a "boost leak check device" to verify without doubt that the plumbing is secure.

#2: Plump a mechanical fuel pressure gauge into the fuel rail. let the fuel system prime, then watch the gauge. When the fuel pump shuts off, the gauge should maintain fuel pressure for a while. If you notice it bleeds of quickly, then there is a fuel leak somewhere, probably still an O-ring.

Once you have that sorted- you can investigate situations with the tune, i.e. the maf and it's parabolic voltage, various sensors etc...

[titangts]

I'll throw in my .2c...

what again is your Vac at during idle (ex. -21)...you said in the OP, 6.5??? if so thats DEFF your issue. which is a hardcore boost leak somewhere.

Also, your temp sensor has NOTHING to do with allowing your car to reach full operating temps. All the sensor does is tell the ecu whats going on/move the needle on the cluster. Your cooling system is 100% mechanical (beside and E-fan).. nothing electrical about it.

Boost leak test, boost leak test.

and 100% FOR SURE. if you are running a NISMO AFPR you should always, always always run a fuel gauge with it. the adjustable regulator is completely useless without a gauge. Just like people who install a SAFC without a wide band..

fuel test, boost leak test. next on the list.

[Croustibat]

I'll throw in my .2c...

what again is your Vac at during idle (ex. -21)...you said in the OP, 6.5??? if so thats DEFF your issue. which is a hardcore boost leak somewhere.

Also, your temp sensor has NOTHING to do with allowing your car to reach full operating temps. All the sensor does is tell the ecu whats going on/move the needle on the cluster. Your cooling system is 100% mechanical (beside and E-fan).. nothing electrical about it.

Boost leak test, boost leak test.

and 100% FOR SURE. if you are running a NISMO AFPR you should always, always always run a fuel gauge with it. the adjustable regulator is completely useless without a gauge. Just like people who install a SAFC without a wide band..

fuel test, boost leak test. next on the list.

Please, do not post when you dont know what you are talking about.

The ecu uses a coolant sensor to enrich mixture and pull timing. Come again.

[rps_jrdn]

your 100% sure maf is good?

[matts13vert]

Its your ecu. I had the same issue at the track. Called Enthalpy and they fixed my ecu havent had a problem since.

Does it go lean under moderate to wot?

Not my car or video but the EXACT same symptoms my tune was causing.
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