Idling AFR's 10.0-.8; No Boost Leaks
 

Ok so I have a 03 Evo 8 with ONLY 23k on it. Has NOT seen a road in two years. ALso my mods in my signature besides the intake manifold. I went back to stock just to see if it would fic my problem.

I cant figure it out i did multiple boost leak tests no leaks at all.

Yet my car will idle but in like 10's for a afr. And when i give it gas just in nuetral i get this like surging sound and its just very hestitant. Cant put it under a load to drive it at all.

Im not sure what it could be. I am using a jdm map sensor but its reading correctly it seems in evo scan and mitsulogger. Also Im getting no fuel trims at all.

I am also not pulling any codes from scan tech or evo scan.

Anyone have any ideas or any other questions that they might have to check or what ever let me know please.

Thanks Jeremy

injectors / o2 sensor....how stock did you go?

I still have cams, injectors, fuel rail, intake, boost controller. Thats about it. I am working with 4ws to tune it. But I am having problems figuring out the problem.

check the maf sensor wiring?

Maf/wiring/Map/TPS/ICS - are you getting a strong Spark at the plugs?? have seen this problem happen due to bad coilpack earthing, car would barely run, and rich AFR's symptons similar to a boost leak.

I got the same thing it's want to stay between 10.5 to 11. If I put on the A/C it will go to mid 13.

Running the FPR still? Make sure idle fuel pressure matches stock. I think its like 33psi at idle and 43psi with the vacuum hose removed (and the hose is plugged). Also make sure the Front O2 sensor is cycling in closed loop when the engine is warm and at idle. Should cycle up and down from around .2 to .7 volts at least. If a coolant temp sensor is bad, the car will stay in open loop which can cause this.

Well for your power level a FPR is pointless I would rip that off and not even worry about it. How long have you had the cams in? Who did the install? Do you know if the CAS was installed correctly after you took it off. Thats shouldn't correlate to the rich AFR I wouldn't think but it can make your car not drive.

If my coolant temp sensor was bad then it wouldnt be showing me the temp right ? plus on evo scan im getting a reading from it.

My fuel pressure is also right on dot.

The only thing i have been contemplating was the o2 sensor. But im getting a reading from both front and back. Ill have to check and see what voltage though.

So front should read between .2-.7 ?

where is the cas located exactly ? Ive never checked it but wouldnt it throw a code ?

Yeah, it should look like this on the front O2 sensor graph:

http://www.picotech.com/auto/graphics/zirconia.png

If its pegged reallly low (in the .9 volt range) that might be fine since its just telling the ECU that you're running WAY too rich because you are. That would mean your fuel trims are maxed out and the ECU just can't lean it out enough which points us to the injector scaling and MAF scaling usually. This usually means there is a big ol' boost leak but you said you are CERTAIN there isn't any. Have you messed with ECUFlash at all? The open loop tables might be set wrong too, causing you to be in open loop at idle.

I got rid of all the patchs and stuff. I took out the mod'd xml and brought it the original plain xml.

Then flashed my car back to its rom that was tuned by 4WS. We are still in the process but cant figure out why its doing this were down to it being the front o2 sensor.

I remember earlier today the front o2 sensor reading being low on evo scan and mitsulogger. I just got to check the logs real quick.

looking at the logs in mitsulogger its shows it starting at .9 then going to a .7 while idling warmed up.

Then in Evo Scan it shows it in the .3 going to a .8 while idling warmed up.

Also again no fuel trims showing in either of them Mitsulogger reads 0.

While Evo Scan reads 100. But at one point i did get a reading but it was at a later date but then it stopped showing them again.

Is the car driveable? You live like 20 minutes from me if you wanted to swing by with it sometime.

The first thing I noticed is you scaled your PTE 680cc injectors to 680cc's which usually wouldn't be the case and would cause a lean condition (most would start in the 625 range). Second, your idle timing is 15 degrees which is crazy high in my opinion. You might not be getting full combustion and raw fuel is goign out of the exhaust. Try bringing the timing down to around 10 degrees and see if the AFR's go down at all. I normally don't like seeing timing over 10 degree's at idle with the majority of cams.