Cylinder 6 Misfire...

I have a 1999 Tacoma 3.4 v6 and I've recently noticed I have a cylinder 6 misfire with an OBDII code. Hard starting, terrible gas mileage, almost no power, and a flashing check engine light when I full throttle. I got a new fuel and air filter as soon as I got the truck. It gets spark on all 6 cylinders, It gets adequate air, the only two things I haven't checked is the fuel pressure and compression, but I am pretty sure it's just injectors as the fuel has been contaminated from sitting for a few years, hence replacing the fuel filter, and there was definitely water in the filter and lines, and the fuel is now fresh and clean. The reason I believe it's fuel injectors is one: I don't want to believe I have low compression, two: I run very lean, and as far as I know is not a symptom of low compression, and three: the fuel was contaminated, previously stated. Can anyone confirm what's going on?

 

Nope. Only you can.

Replacing the injectors is pretty easy. Pick up the upgraded Denso set from Motorwest, watch the timmy video, and send it. I suggest using the supplied super lube on the o rings rather than the gas in the timmy video.

Check your compression, and follow up with a leak down test if you have low compression. It's really the only way to diagnose things. We can't do that stuff via the internet.

 

Swap the wires with another cylinder to see if the misfire changes location? How old are the coils/plugs/wires? When my 3.4's coil/wires/plugs had a lot of miles the truck would run fine but misfire when I pushed the pedal heavily.

 

You didn't mention anything about plugs, wires, or coil-packs.
Had a cyl 6 misfire on my 3.4, and changed out the plugs, coils & wires, and POOF! Went away and much better mileage.

 

I agree with the plugs and wires- but not the coil. If it were the coil, there would be a misfire on two cylinders.

 

Whats the CEL codes?

 

I replaced all of my coils along with wires & plugs because I had 166,000 miles, and they were original; sure didn't hurt.

 

That's not wrong. But parts cannons can be a bad thing in troubleshooting. You don't learn what the actual cause of the issue was- just that a list of new parts fixed it.

 

Depends……
Is it “parts cannons” or PM’ing? (Preventative maintenance)?
I see OEM on an ignition system with 166,000 miles, I am pretty sure it’s a good bet to replace it!

 

Misfire cylinder 6. no other CEL's atm

 

I'm gonna replace the injectors here in a few days. spark plugs are new but wires aren't. Although I checked to see and all 6 cylinders have spark.

 

I threw a misfire code last year, and the truck started back firing right away. Ran like shit all the way home. Swapped a plug wire around and the misfire code went to the new cylinder. Installed new plugs and wires, and problem solved. Truck ran so much better and my gas milage improved quite a bit. Went from 15 just driving around back to 17-18 if I keep my foot out of the peddle. Now getting 23.4-24 mpg on the highway running 2250 rpm or 73 mph. This information is according to my Scan Gauge readout.