I just installed my engine last week and everything is the same as the previous engine, but when i started it up for the first time, it threw a code saying: random misfire, misfire on cylinder 1, and misfire on cylinder 6. I checked all sensors that i knew of and all looked ok, all the injector harnesses look to be tight, i changed the ignitor and coil and that did not change the problem, i put the car on a scope and the plugs and wires were showing fine, and put a screwdriver to the injector base to listen to the pulse and they seem to be fine, and last of all the car seems to run fine with no signs of having a misfire. Any suggestions of what this might be, or is there anything that i might need to check? I have a e-manage, and 500cc injectors in the stock fuel rail. Like i said before, nothing has changed between motors and the other one never threw a code. Please help.

-Jason

 

reset the ecu, and drive the car around to see if the cel comes on again.

 

i did and it does

 

what injectors are u running? do you have an accompanying resistor setup if necessary? there is a possibility that you are getting misfires from the injectors overheating and not opening...i've dealt with a problem like that before. if you could give us more info on your setup to help us help you. good luck

 

i am running precision 500cc injectors that do not require a resistor, just a pigtail to go into the original wiring. i have a greddy emanage, sc400 maf, msd sci, and turbo setup. Everything else is stock. i listened to the pulse and it sounded fine, but i don't know. anything else vipsoarer?

 

check your plugs, make sure they are gapped right!

 

hey aliga- i have ngk 3330's i thought they are not supposed to be gapped.

 

always check the gapping. some arent gapped correctly from the factory along with that different motors/altitude/setup is different and its own gapping is needed. so check and adjust to fit your car.

 

other than gapping issues, i have a double stacked 2jz-gte head gasket which makes my compression really low and i have retarded my timing by 4 degrees, would this retardation of timing maybe be a cause of my misfire.

 

How dose it detect misfire? This may be more important than the code it's self. As you have already said.

Try advancing you timing back to stock, just don't boost the crap out it. Might not be a bad idea to also add some high octane as a safety measure, while you advance timing.

Good luck

 

check the knock sensor for correct ohms and such to make sure its not just a coincidental error from a bad sensor. if your base timing is set back 4 degrees i would take it back to stock and just make sure you use the gas you usually run in it to see if you still get the knock. just dont beat on it constantly while your checking things out. if all checks out i would take it to the tuner for a re-tune so that they can read out your a/f along with timing under full boost and such

 

ok, well i fixed the problem. i had told my mechanic to retard my timing, instead he had advanced it 4 degrees, well it is at base 10 and runs perfect. thanks for the help anyway.