Misfire on cylinder 5 p0305

[camma83]

Misfire on cylinder 5 p0305 (problem solved)

Ok i have an issue, I have an 2004 4.0l and i have two codes that just showed up today. p0305 and p0316 since then I have replace the coil-pack, plug wires and plugs. I currently don't have access to get cylinder pressures or preform a leak down test. I am debating to replace that #5 injector to see if that is the problem. But what are some other ideas what might be wrong..... I am kinda stumped at the moment.

 

[TheTopher]

Instead of just replacing it and calling it good, pull that plug and actually verify the spark. Also run the engine a bit before you pull it. If it's wet you know your injector is working. Make sure you let the fuel evaporate before you do the spark test, of course.

 

[adsm08]

Did you get the code cleared? Later Ford's have a strategy to protect the converters. They shut down fuel injectors when bad misfires are detected. If it's an ignition related miss that can keep making it misfire even after the problem is fixed, until the code is clear.

Try getting the code cleared out and see if it starts running any better. I've seen it before.

 

[camma83]

I have cleared out the code after each thing i do to it to try to solve the problem, That's a good idea to see if the plug is wet with fuel to see if the injector is firing

thanks for the replys, I will check that tonight.

 

[adsm08]

Yup. If you are clearing the codes and it's not helping run it for a minute and then pull the plug to see if you are getting any fuel.

If not, go get a noid light to check the circuit. Those are cheaper than an injector.

 

[camma83]

well here's the deal, I ran the compression on all cylinders and they are very close to each other. problem still exists and i didn't have a lot of time to work on the truck this weekend. The problem seems to come and go at times, so i am thinking it might be an electrical fitting somewhere not making a great contact somewhere.

 

[camma83]

this problem is driving me up the wall

 

[camma83]

ok, a misfire is still detected. I changed out the injector. The injector is getting voltage. I don't know what to do next. I don't know how to check the return power for the injector that could be bad
what i replace has been plugs, plug wires, coil pack, inject

 

[adsm08]

Get me your VIN. I'll see if there are any known issues with that year and code combo.

 

[camma83]

pm sent thanks

 

[adsm08]

I ran it, but no TSBs came back.

P0316 is a misfire in the first 1000 revs.

I looked through the PC/ED and this is what I've come up with.

Pull your cam syncro out and see if it is damaged.

Then test the ground side of the injector circuit. The coils and injectors are always supplied voltage in key on. They are fired by the PCM breaking the ground side of the circuit.

 

[camma83]

well i recheck the compression and i have 30 psi while running and i did some research that its less then half what it needs to be, I am going to pull the head off after christmas and investigate further.

 

[camma83]

ok I finally had time to check it out and fix the issue, The problem was a broken valve spring. couldn't see it a first look but once it got cleaned up you could see it, it broke just after the first coil around. i ended up spending about a thousand dollars to track down a 6 dollar part..