Missfire cyl 5 and 2

[Jackthewack]

Got my injectors rebuilt by witchhunter performance. And the leakdown test can tell if your valve could be leaking and the compression check is inital copresion and may not tell all. Idk im just thinking about other things to try

 

[Jackthewack]

I did a leak down test on the 2 bad cylinders and it seems i might have some leaking intske valves. I could hear it leaking when i opened the throttle body. The tested showed like 20% leak but it was in the green part of the gauge so i guess that means it should be in the ok but i dont like that i can hear it in the intake

 

[Jackthewack]

Update. I ran top engine cleaner. And then had to take a trip a few days latter. The drive was about 3 hours one way. About an hour in the Truck had a strange almost hickup i guess and the check eng light turned off and truck ran great the whole way there and back! But the next day didnt want to start and when it did it smelled really bad and ran like shit. Now its back to the normal random miss and check engine light same codes.

 

[Jackthewack]

Changed my maf to the 99+ style and am going to clean the conector for the ecm and put some electric greese on it

 

[Jackthewack]

Update. It started missing hard on me constantly now. That actually really helped diagnose it. I put a noid light on the injector and found 5 was not getting any pulse. It had power but the injector is controled using ground from the ecm. I checked at the ecm and found that it was not sending the pulse. I ordered another ecm and should get it next week so i will update if it fixed my issue of not.

 

[Jackthewack]

ecm did not fix it. ran new wire from ecm to injector. still no pulse. do i have another bad ecu? what am i missing here? are there any other signals i need to be checking?

 

[4Reak Show]

ecm did not fix it. ran new wire from ecm to injector. still no pulse. do i have another bad ecu? what am i missing here? are there any other signals i need to be checking?

I'm just grasping at straws here for you, but have you looked into the igniter? It's the little black box near the air cleaner. I forget exactly if it controls spark or fuel or just sends a signal to ECM when to fire stuff. But I know it's important and can do weird stuff. You ruled out ECM, wiring, and injector. Time to keep looking

Edit: just checked in information system and it doesn't say anything about igniter relating to fuel. That device seems solely responsible for ignition. Any chance that when the ECM confirms a misfire it shuts down the injector?

Only other thought would be something weird like the cam sensor tone ring missing a tooth for #5 but I would think that would set a different code. Pulling upper timing cover and looking at passenger camshaft sprocket would confirm that idea.

 

[Jackthewack]

i actually did swap the igniter with another one thinking maybe it would help didnt help. i will try and see if its missing any teeth. but it is strange that the issue was only sometimes and now its all the time. i did change the cam sensor about 2 weeks ago but no fix there either. im starting to get to the point i might just get rid of the truck

 

[tomtundra]

Did the misfire start after you changed the plug wires, or is that why you changed them?

 

[Jackthewack]

i changed them for maintance and the misfire started one day out of no where i have pulled the plugs and swaped plugs and the wires are in the corect location. im getting desperate why is my runner a pos and my wifes is perfrect never has an issue

 

[tomtundra]

Understand your frustration, hope you're able to isolate and fix. Have you check the new wires, swapped them or just tried new ones? Seems strange your issue began after you changed them, maybe you have faulty wire.

 

[krenaud33]

All injectors are good? My misfire was an injector. Took me awhile to figure out it was truely the injector

Sent from my SM-S765C using Tapatalk

 

[waheednasir]

Change the fuel injectors! I had the same problem and after I changed the injectors now everything is good.

 

[Jackthewack]

i got some injectors and had them rebuilt by witchhunter like 4 months ago. i finally got some of it fixed. got another ecm and now i have injector pulse! but found that the injector had 8 ohms the others all had 13.4-14.8 ohms. i threw in an old injector that i knew was ok. truck runs good now but i have a flashing check light at highway speeds code is for #5 AND 2 same as befor. i had this happen a while back and it went away but i never found what it was. i checked all the vacuum hoses and everthing i removed idk. the missfire is not felt no lack of power idk why my truck hates me.

 

[Jackthewack]

Finally fixed it guys.my crank sprocket was f**kd up! Crank bolt was loose i guess last guy in there didnt tighten it enough. The sprocket was able to move and it ate it up. So new timing belt kit crank sproket and crank key way.now she runs awesome way more power starts right up no rich smell from exhaust! I finally found it! Thanks for all your help guys.

 

[LittleCaesar]

Good to hear.

There are reasons not to deviate from 217ftlbs of torque.

 

[Jackthewack]

Yeah thats no joke. I found alot of loose bolts in there and it makes me want to go over every bolt on the truck now! I already checked all the suspension bolts when i did my ball joins and lift. But i want to go over it all now