Cylinder 1 misfire

Thank you so much.

 

Nothing worked, a mechanic told me to try something called JB 80 injector cleaner.

 

Is it a cold start misfire or does it do it when it gets hot?
Are you losing any coolant?

 

check alternator output, check battery cables and grounds for loose or corrosion (on frame and engine). If the cables are good, a failing alternator is suspect.

Sounds like the battery might be marginal, don't be surprised if it tanks soon. If it's old, might be a good place to start

A shorted battery may still start the engine but it will cause funky symptoms like random trouble codes and weird electrical behavior. the alternator will also get stressed trying to constantly charge an infinite "hole" of voltage in the battery. And vice versa, a weak alternator will stress the battery..

Remember, these vehicles run on electricity. Every computer module in the truck (inc the pcm) needs a steady supply of power to do its job. That low battery code is the computers way of saying "hey, where'd my 12 volts go?"

 

Thank you for advice. The coolant level has not moved in a while, it started, ran fine after I changed plug and coil but next morning after warming up it began misfiring. I had battery tested twice and came back ok. Will try to have alternator tested in next few days. A friend suggested a pressure clean of injectors to see if that is problem. Would appreciate any help offered, thank you to all of you.

 

Hope someone can help, I have to disconnect fuel line from fuel rail to try an injector pressure clean. I see 2 orange (what I think are clips) connecting line to rail. Don't want to break them so how do I do this? 2006 taco 2.7 liter

 

Also, I should remove the fuel pump fuse but fuse box lid under hood does not say which one it is. Any help would be greatly appreciated. If this injector clean works I will post the YouTube site for anyone interested. Thank you.

 

Picture of said connection?

There is no fuel pump fuse, remove the C OPN Relay or FUEL PMP Relay to prevent the fuel pump from running (be aware this may set a code in the PCM).

 

I can’t find a good picture.
But you need to pull the “checker” up.
Once it’s up, you should see 2 pinch points.
Pinch the clip, and pull out on the line.

Sometimes, it helps if you press the line in first, then pull out.

 

Thank you both very much, hope to resolve this tomorrow.

 

Was that sparkplug wet?

You don't need to pull the injector to see if fuel is causing a missfire. I assume you threw the old sparkplug away... Next time, learn to "read" the old sparkplugs. What color/smell, etc.

You have a 2006 4.0. that makes it very likely
To be a heas gasket leak. I put a bottle of k-seal in my truck and it actually worked.


If you want an injector to stay open, just unplug it from the system and give it 12v directly from the battery.

Obviously, do this NOT while the engine is running.

 

Yes, true lol. I have the 2.7 L and we checked the cylinder and it was wet. My mechanic says we can get a wiring harness at local yard and he can splice in new cylinder 1 wires. We switched coils, plugs with cylinder 2 and still got cylinder 1 misfire so I THINK we have eliminated the other possibilities. Any advice, help or info would be greatly appreciated, lost my beloved dog last week. This truck does not come close to him but I do kinda love it because of driving my son around with his head hanging out the window

 

Was the cylinder wet with fuel or coolant?
Have you confirmed that you do or don’t have spark?
I don’t think I’d go to cutting and splicing on the harness until I know the harness is the issue.

 

Went thru exact same thing with my 6 cylinder 2005 in Sept. Mechanic did exact same things as you have up to now. He also said my injectors were starting to clog. He recommended 2 cans of seafoam into a tank of gas, run it to almost empty and repeat 2-3 times. Seems to have worked.

 

Thank you, it looked like fuel not coolant. I am going to have someone else look at it as well before doing anything with wiring harness. I was told to lift the coil out a bit to see if it's sparking but that's hard to do with the air box on top. Is there another way to check for spark? Thank you all so much for the help, you've all given me great info and I really appreciate it

 

No, you need the coil and plug out to see if it’s getting spark. Coil out and plug in the coil. Then rest the plug on the engine to give it a ground. Crank and look for spark.

 

I have new gas and container of Techron going through system now, don't believe injector is problem but am stumped. Any advice is greatly appreciated.

 

Thank you, will try that.

 

How often does the misfire happen? Is it constant whenever the engine is running? Intermittent?

 

You still haven't said when the misfire occurs or if you did I missed it.
If it's consistent under certain conditions (cold startup, hot driving, under load, idle, etc) that can go a long way in helping to determine the type of misfire.