injector not firing
Thread Starter
Teching In
Joined: Mar 2018
Posts: 2
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injector not firing Hello i am having a problem with my ls swap in my 67c10, I have had the swap for a few years now and just noticed this problem. I felt a miss while cruising after swaping to some new fuel rails, once i hooked up my laptop and started looking i noticed my fuel trims were around 12% normally they are 2-3% . so with the laptop i started to disable injectors every injector, except #3, would make the fuel trims go up to around 20% , #3 had no change. so then i checked the power to that connector and had 12v and then checked the signal wire resistance to ground and was getting a pulse on my multimeter so i think that is good. I bought a new injector and put it in but still no change, when i plugged in the spare injector i could definatly feel it pulsing. i swapped injectors with a different cylinder and problem stayed with #3. so to check mechanical i took the valve cover off just to make sure the valves were opening and they were. Is it possible that the injetor driver in the ecm is not working correctly even though it feels like it is pulsing?
Thread Starter
Teching In
Joined: Mar 2018
Posts: 2
Likes: 0
Well after more troubleshooting i am still having this problem, but now it is injector #1 that is having the problem and injector #3 is working. I have tried new ground wires on the PCM and grounded all the grounds directly to battery, i ran new injector wires to the injectors, put on different injector connectors. removed all engine grounds cleaned them and put them back on. and still having the problem. i can plug a test light into the injector connector and the light does start blinking, so it is getting power and signal from the PCM , i just cannot tell if it is getting it at the right time, or if it is getting the signal everytime it is supposed to fire. I am going to replace the cam and crank sensor as i am thinking that these sensors will be what tells the injecor to fire. does anyone else have any other suggestions on what to check. I do have another PCM but dont want to spend the credits to reflash it until that is the last possiblity. Is there a way to check the injector driver in the ecm to see if it is faulty?
