I am going to swap a coil around today and see if I get a misfire on another cylinder. Any other ideas

 

Swapped a coil out for a good one I had laying around. Same issue. Misfire on cyl 1 code was pretty brief and went away without me clearing it and has not come back.

 

Do you think we are on the right track suspecting an engine performance problem causing the jerking you feel when driving ?

Why don't you change that spark plug for that cyl ? Many times when tightening a spark plug we manage to crack one and it only shows up under load.

You are getting signals that there may be a problem involving #1 cyl.and changing the plug is the easiest thing to start with.

If no change, then we check the coil and don't forget to look for the black arcing marks inside the coil boot.

 

I thought it's engine related since I got that temporary misfire code. My stupid scanner used to always ask me if I wanted to scan engine codes or all systems modules, now it doesn't and I can't figure out how to scan more then just the engine, to see if there's any transmission codes. I swapped out a coil, no change, I'll try inspecting the plug sometime or just swap it out. My other thought was that maybe there's a sticky injector or something, but wouldn't that affect my fuel trims? I don't know, I'll look into the EGR more sometime but like I said before I didn't really think that would cause a misfire, do you?

 

On a side note you got any fixes for the coil hold down bolt threaded insert in the valve cover breaking loose in the valve cover and spinning. Is there an updated part that bites into the cover better. I jb welded one that spun and I think it's the same one that spun again.

 

To try to ans your question,
If some normal passages to each cyl are blocked with carbon, the ones that are open will get too much exhaust and be eligible to misfire.


You might consider, obtaining an extra new coil and use that for swapping if you choose.

A defective coil or shorted coil can cause assorted electronic problems like destroy a driver in the PCM and then when you switch that coil it will destroy another driver in the PCM and now you have 2 missing cyls,, not recommended.

If your coil mounting has metal in the mounting and it uses that for it's ground , that coil will be capable to not work all the time .

 

So I asked chat gpt... I know, I know... I told it I have good fuel trims, I pressed on the brake pedal lightly while driving to try to get the TC to unlock while giving it throttle and symptoms remained and that I had basically no misfire codes (because it was a really brief pending code) and that I really can't figure out what is was and it said one thing to check is the ac voltage ripple at the battery which was .27 which is a sign of a failing diode and it said anything above .2-.25 is enough to disrupt electrical signals in the PCM such as ignition and fuel injection. Then it said to check dc voltage at the battery with every electrical thing turned on(headlights, blower on high, rear defrost, etc) and I read 13.1 volts at idle and that's with a brand new battery. I don't know anything about ac ripple but it does make sense to me that it should be charging more then 13.1 volts with everything turned on. What are your thoughts, sound right, kinda right, bunch of bull****?

 

Checking voltage coming out of the alt is not a reliable test. A better test is to leave headlamps on for 30 seconds to pull battery power down. Then when you start the engine the alt should put out all it can, then you will know if it can produce if necessary.That output is measured in AMPS not volts.

If your vehicle's alt is rated at 60 Amps , that is what it should show when the engine is started. Most folks don't have the correct meter to measure that many amps.

Vehicle voltages vary by vehicle and some use 15 volts as correct , while some use 13+. Some systems will put the charging lamp out if charging only 1 amp and the system can be pulling 15 amps, so that allows the battery to become depleted. Don't be misled by using just voltages for checking charging systems.

It is cheaper to install a voltmeter than an ammeter .
One thing a voltmeter does is : tells you the (SOC) , state of charge of the battery. Depending on the regulator within the alt, it will usually try to maintain the regulated state of charge.

 

It was the EGR pressure sensor. Drives good now.

 

Thank You for the update !