Multiple Codes, Need Help! + DTC says I have a bad MAF?

[Black420RS]

Hi

just wondering if someone could have any idea of what is happening in my car...


some good day he started to hesitate really weird... and trow the CEL on so I put the code reader and it said that i had Injector #3 open

so checking the injector harness I found the ground wire for that injector touching a hot spot so it was peeled/melted and producing the fault...

everything went normal, that was 3 weeks ago... yesterday driving back home had the CEL on again so I put again the code reader and now i have 3 codes...

P0300 Random/Multiple Cylinder Misfire Detected

P0203 Cylinder 3 Injector Circuit Malfunction

P0103 Mass Air Flow (MAF) Circuit High Input

so... I changed the spark plug in injector #3, swapped injectors 3 and 4, changed the coil pack, swapped cylinder 2 and 3 spark plug cables, deleted the codes and after a 10 minutes drive I have the same codes again...

compression test shows my cylinders in 175-185 ish

I am running since 2 months ago (or so) a new crank position sensor because the old one died

my mods that could be related to this are are AFX ECU, crane 12's, 60 mm TB, P&P IM, Adjustable cam gears, BRK5EIX all those been there for about 2 years or so

any help would be really appreciated... and if I made a mistake sorry about my English but this is not my native language


EDIT: BTW the car runs fine, my dyno butt doesn't feel any loss in power when driving it but sometimes he idles a little rough...

 

[jayson427]

does your car ever die and not want to start after it starts acting really weird? im pretty sure i know what your talking about when you say weird since i had this problem last summer. i have an afx ecu too with a built motor but last year when it started to warm up my car did not want to run good. seemed like when it ran hard and it was around 90+ degrees i would start to misfire down the road for no reason, loss of power when this happens too. a few times it would die and it wouldnt start till it cooled down a little bit. i changed my plugs coil and wires but it still did it, i let my car sit for a month put a new coil on it and it never happend again.

have you tried a new injector harness? you might have some damaged wires around the throttle body to the injectors since they get a lot of heat and sometimes fry up. i would get a volt meter and test for good power around your problem area. and to get a maf code is weird since we dont have one i know it says circuit so that can mean anywhere between the ecu to the sensor. i would check out your map sensor wires.

 

[Black420RS]

no, the car never dies, no problems with starting, no loss of power

I checked the injector harness and it looks good,

UPDATE:

ok, I plugged a USB-OBDII interface in my car and the readings at idle on my IM where around 50 kpa... I don't know if that is good or bad... well, the thing is that I changed the MAP sensor for a spare that i had stored and the reading are now around 40-42 kpa... also don't know is that is good or bad but is lower than before...

could that be the problem related with the MAF code??? hopefully it is...

tomorrow I will remove the IM and the injectors to make a deep check on the harness (and change it to a port matched OBX IM) so I will let you know if i found something there...

any other ideas are more than welcome because I am running out of them..

 

[bullettdsm]

Yeah, change your maf. Maybe put a 1g on there instead

Lol, I think you did the right thing in trying a known good map. I wonder if that code has something to do with what Dave does with the ECU. I believe p0107 (or 8) is our map code.

As Jayson was saying, suspect the wiring (especially when you already had a bad wire within the harness. AND moving the injector didn't move the misfire). An injector harness is an easy start because its very simple to switch out.

 

[talontorque]

your random miss probably has to do with your injector code. Also try cleaning your maf to see if it helps.

sry I didnt see your non turbo never mind cleaning a maf that isn't there