ok, i can't seem to get away from this car misfiring. sometimes will get po301 (#1 misfire) sometimes po300 (all misfire) now getting warnings from the enamage of incorrect ignition input signal sometimes on ch6 then other times ch6 and ch1. doesn't matter if the car is cold or hot. sometimes it will run fine for an hour then for no reason start to misfire.
intake leaks have been checked, 4 new coils, wiring is good, spark plugs not fouled, sensors cleaned, codes cleared, parameters set correctly on emanage. i either need an occiliscope now or just take it to nissan and have them run their scanner on it. hopefully it should be very apparent when they hook it up what is causing this problem. i know alot of people have had similar issues, was there something that was done to fix it or did it just mysteriously go away. any help or suggestions would be greatly appreciated.

 

I'm going to guess that you have a bad e-manage.. Sorry if you posted in another thread that you tried another one..

 

My buddy & I were talking about your motor. We came up with a new assumption. Don't take this the wrong way, I don't mean to rain on your parade at all. Just a guess,that's all.
If there are any metal fragments magnetically attaching to the sensors, then something was put together wrong. The majority of the motor consists of aluminum. Aluminum can't be positively charged & isn't attracted to any magnetic metals. The part that is shearing is not aluminum because aluminum can't cling on to another metal(sensors). The only metal parts in the motor that will magnetically cling to another metal are the sleeves,crank,cams,& valves. So it seems that one of the above are slightly shearing away causing metal(non aluminum) fragments to float in your oil. Since the sensors have an electrical current running through them, they are positively charged(magnets) & will attract most metals except aluminum.
There should be no metal fragments in your motor
period.

Check to see if there is any more metal on your sensors.
Hopefully it's just your brake in period but it seems kinda odd.
Good luck

 

I had horrible misfires... but thats because I wired my injectors backwards.

56
34
12

vs

65
43
21

I'm a bone head so once I found this, all my problems went away. The car drove, and the misfires wern't consistent... It even had TONS of power. I was surprised it started with such an oversight.


If you're using the EU I have a brand new one sitting in a box... A guy @ work has a full scanner I may able to bum.

spdkils

BTW I pmed my #.

 

You can bypass the timing harness and rule out the emanage. Just run a jumper from the 12 input/output wires.

 

ok, i hate to say to say it as all these are good ideas, but already ckecked all ofg the above.

 

no more metal has formed on the sensors. after other motor break ins if you look at the oil being poured out after intial break in it can look like a metalic paint. i put new cams in it and they come with a kinda rough surface to break in. i'm sure that is what it was. nothing big mind you, just kind of a metal slurry. the motor runs perfect when it doesn't misfire. no knocks no nothing. have put a mechanics stethoscope (sp?) on it also and heard nothing.

 

i have gone over the wiring many times now. nothing is wired incorrect. i thought i had it cornered tonight with a bad connection in the emanage ignition harness, but it ran good a couple times, then started to misfire again. makes me feel i am looking in the right direction, then it goes back to being fuked up. got your pm too. ya, i need a drink now. the car almost got a hammer through the hood tonight. been about 3-4 weeks trying to find this problem now. nissan dealer doesn't even want to look at it because they seem scared. been to torque freaks and they couldn't find it either. looks like i am the only one to figure it out. so when i do, i'm puttin a bunch of gold stars on the fridge for myself!!!!! hahaha

 

already did that. car ran the same. actually i bypassed the whole emanage and put the stock injectors in too. still misfired. then i thought to look at the sensors for debris. pulled the cam sensors and found some. wiped it off, and the car ran perfect for an hour with the stock ecu and injectors. hooked up the 660"s again and the emanage and ran good for awhile then went back to misfire. i figured out tonight the only reference for the stock ecu to set a PO300-po306 code is from the crank pos. sensor and rpm. it doesn't reference the sensors for this code. the sensors have their own code for random outputs. which is pointing me back to a mechanical prob. most of my coils are new, and have switched them around. still getting the same codes from the ecu and emanage. but tonight i did eliminate the incorrect #1 signal on the emanage. now it is down to #6. the stock ecu is still saying po300 (random misfire) but can tell it is just one cylinder and not others. it will actually , about 50% of the time, not misfire right on start up but will start about 20 secs into run time. but the emanage will catch it right when it starts to happen and blink red with a "incorrect ch6 input signal" but the stock ecu will not even see it.
again, i have gone through all my wiring and it is correct. put a volt meter on the input and output of all ignition signals and found them to have the same output across the board. the volt meter will not read wave forms (cause it doesn't react fast enough) but since it doesn't read that fast it gives a solid reading out, and all were the same. i need a ossiliscope to look for the bad one. still thinking it might be a bad connnection in the emanage harness. as it did run good when i started to mess with it and test it. but went back to crap. the dealer i bought the car from will not call me back now to even look at it with the consult2, but that might show a little more. about to go midevil on them for being morons and not letting me see what it says.
well now you know abit more of what i am dealing with. i'm sure it will be simple when it is found, it just needs to be found. i went through alot of care putting everything together, and it runs like a raped ape when not misfiring, but don't want to drive with this prob going on.
and to top it off, i went out in my vette the other night with built motor (550hp +150 shot) and that ***** through up the misfire code toooo.!!!!
my luck will change!!!!

 

It can be a real pain to find a problem that is intermittent. I am sure that you will figure it out. Be patient and good luck.

 

My Infiniti dealer just replaced my crank angle sensor in response to a TSB. I never had overt symptoms of trouble, like mis-fires, but they replaced it even so. Could your CAS be tormenting you...?

 

Are you running 660cc injectors? High or low impedence?

 

What year is your car?

 

i need to test it with an occiliscope, but i don't think it is the problem. i just got a bunch of shielded wire and plan to wire the cas and both the cam signals. i have already had mine replaced also from the dealer. had the cas comletely fail out of town about a year ago.

 

siemens 660's high impedance.

 

03 touring #42, lol.

 

bump

 

Does your car run rich at idle or during part throttle? Does the A/F ratio wander at idle or stay pegged at a particular value? Does it ever seem to hesitate slightly at lower RPMs (i.e. boost level still at vacuuum)?

--Steve

 

Is it possible something is wrong w/ your ECU?

 

the a/f will wander slightly at idle, but i havn't done a reflash yet and it is trying to idle at 650. so i am guessing the ecu is just trying to figure it out. when running good it doesn't have hardly any hesitation. one thing is though, if i keep my foot at constant throttle when the car is driving, say like keeping 55 or so, the a/f will either go full rich, 9-1, or full lean, 19-1. seems to be right around 2v on the maf. if i give it a little throttle it will go right to an acceptable a/f and run good. now if the car is running but not driving, and i hold the throttle in the same position, it will start to mis abit and through up the po300 random misfire code.
i checked all my ignition wiring today for breaks or bad connections and came up with nothing. tested it through the eu also, with power on and off. then car running also. it seems as though i might not be recieving an output signal on #1 from the emanage ultimate. i am checking with a multimeter and not a oscilliscope though but the output on #1 did not match the others while the inputs were all the same.
here is another point, i can rev the motor up and down and will not get a po300 code, just when i hold the throttle steady, but only when the car is not in motion. i could sit there and rev the motor all day it seems and have no problems at all and no codes from the ecu. but will still get an incorrect ignition input on ch6 and ch1 from the emanage.
hoping this makes sence to someone cause it is really tapping me for resources here. nissan dealer doesn't even want to put it on their consult 2 either to see if i can find something happening on that.