Cylinder 1 Misfire
 

Compression test results:

#1 = 200 psi
#2 = 210 psi
#3 = 205 psi
#4 = 205 psi

This is perfectly within normal range right? I read 14 psi between the valves. lol now I'm even more confused. Could this be electrical?

Idles fine? Is it only when you accelerate? What if you cruise steady at 4K RPM?

No this problem occurs while both idling and driving, but it doesn't occur all the time. It will be driving fine for a bit, then all of the sudden it will drop a cylinder. When misfiring, it sputters when accelerating, and when idling the car almost lurches. I sometimes will put it in neutral to keep it from jumping while I'm stopped at a red light for example.

Further information: I went ahead and dropped a new fuel injector on the #1 last night. It seems to be driving fine at the moment, but I am very hesitant to say this fixed the problem. Seems like every time I mess with the engine my box will run great for a short bit, then it will start acting up again. I put a coil pack on the #1....one day good, then started again. I switched the #1 & #3 coil pack....two days good, then started again. I put 4 new plugs on it....about 5 days good, then started misfiring again. I put a new fuel injector on the #1...I'll let you know how it goes.

I have an 06 Xb 65k, having the same problem, please keep us posted if you figure it out

So far, 5 days no problems. I need more help though, can anybody tell me if its possible to test a single removed fuel injector to see if it has an issue with decreased flow? I have been told, and I've read that fuel injectors are built tough, and that they rarely go bad or break. If it does occur, then its more than likely a manufacturing issue and it would fail somewhat quickly. I'm also, much more likely to believe that some impurity in the fuel may have clogged the injector, and that's why the problem was on again off again. But I would like to make sure. I will also try to post a pic of the injector tomorrow just to get some reactions about whether it looks dirty or blocked up.

There are special stands that can test injector flow, leak down, spray pattern, but nobody wastes their time with it anymore. Cheaper to replace.

I thought I read that it was cheaper to replace injectors than to clean them. Only thing is $100 per injector is a pain, especially if you aren't sure what is causing the problem. I would just like to be certain that the fuel injector actually was the problem, instead of waiting for it to misfire again.

For those having the same issue with a misfiring cylinder here is what I suggest you do:

FIRST, check the plugs- check to see if one has blown. If its been a bit since they were gapped/changed then you might just want to replace them (Not that expensive, stock plugs cost about $10 for 4).

SECOND, if plugs are good and the cylinder is still misfiring, swap the Coil Pack on the misfiring cylinder for one on another cylinder. If the same cylinder misfires again move to the third step. If the suspected coil pack makes a different cylinder misfire, then replace the coil pack. It's more than likely bad. A new coil pack cost about $80-90, I think I paid $88.

THIRD, if plugs and coil packs are ok, then the injector is likely the issue. You have two options at this point. 1) Get the injectors cleaned by a mechanic (most people don't have the tools or know how to clean them properly). This, from what I understand is rather pricey. I never checked, sorry. 2) Replace the injector on the misfiring cylinder. (new injector cost me about $100).

**There is, from what I understand, the possiblitity that it could an electrical wiring issue. If you want to check for a bad connection, unplug/plug you wiring connectors that attach to the Coil Pack (this you will have to do to remove the coil pack). Also, you may want to check the wiring connectors that attach to the ECM. The ECM is located behind the glovebox within the dash, just above where the passengers feet rest.

If anyone reads this thread and solves their problem it would be really helpful to all if you would post a reply stating what solved your cylinder misfire. This would give us all a small sample of the number of issues and what was done.

I was lucky. I have an 05 xA with about 130K on it. Same problem. Went to AutoZone and had the code read with number 1 missfire. Found out that by leaving the valve cover (plastic cover) water had gotten into the engine bay and sit where the plugs are. Plug number one was all rusted. Change it and the car ran fine. Now the cover is back on.

I think you may want to chase an electrical problem with the wiring going to the #1 coil pack. I don't see how an injector would be good then bad then good again.

Check out ebay for injectors, I saw a 4-pack (refurbs) for $100- not sure of the brand or the quality. Also partsgeek.com is reasonable and easy to navigate. Had cyl 1 misfire also, fortunately it was just the coil, which you can also get much cheaper online if you can afford to let the car sit til it comes in.

Hello,
I had the same problem on my 06 yesterday. 301 error, running rough, lights on dash on and off like Christmas lights. I pulled the #1 plug and it was all rusted. The other 3 were fine. I replaced all 4, but noticed that #1 plug tube had a greasy gunk to it. After cleaning it the first time everything was fine. Today, I drove my 200 mile commute and it started again as I got into it to come home. I got home, pulled the coil, and there is water in the plug tunnel. I run the engine with the cover off, and it has been raining today, but I do not see any evidence of water on top of the engine. Is it possible my head gasket is leaking into the plug tunnel?
Help, I need to go to work tomorrow morning at 6!

I had the cover off when mine gad the issue. I only see water sitting where the plug/coil when the car was Park. As you drive the heat from the engine kinda evaporate the water so you won't see any water.

Not if you get them cleaned and flowed at RCEng., the cost is 24 $ per injector.

http://www.rceng.com/Fuel-Injector-Cleaning-P43C0.aspx

The only thing is you'll be out for a few days. Turn around is quick.

I can't see water getting into only #1. I am suspicious of the head gasket.

I drove 100 miles to work today and it ran fine.
I think as it sits, the water collects in the plug tunnel. This has to be a head gasket issue. I will see how it runs on the way home.

The way that our engine sit, it lean toward plug one. I notice this when I saw water sitting around plug one and not at the other three plug.

Drove home over 100 miles, and in traffic, and no problems.(?)

4 months later and my box hasn't done it again. The last thing I did was to change the fuel injector on the bad cylinder indicated. I still suggest following my earlier post about trying to diagnose the issue.

Good luck if you have the problem. If you want to ask me any questions you can message me directly. Not sure what help I'll be, but I'm willing to offer what I can.

I have not had the problem since I replaced the plugs and dried out the cylinder.
Going on about 3000 miles since then and just crossed over 320000.

I'm having the same issue on number 4! I can't seem to figure out why. Turns out the threading was messed up, burnt the spark plug and coil, replaced both, fixed threading with insert, and still misfiring. I then swapped injector 3 with 4 to see if misfire would change cylinders and it didn't. Still get misfire on 4. any ideas?

Same thing here, though no rust. Unless it's from the belt pulleys, aluminum doesn't rust. There is a rusty stripe under my hood above the belts, so that's where it'd be coming from if anywhere. Water happens to cyl 1 because it's the closest to the belts, which throw the water on top. I guess any could be exposed though.

Why are some of you saying it's a head-gasket issue? The head gasket wouldn't put water into the tube, since the gasket is BELOW the head (where the plug is). Even if the valve cover gasket (not the same thing) was leaking, show me where the "water" would be getting in? It's nothing but oil and cams in there. Here's mine:
http://imageshack.us/a/img94/4407/img0240hnv.jpg

Also, why are we talking about gap? The 1NZ-FE suggests pre-gapped Iridium plugs.

Thanks to this forum I fixed it. Thank you all.
 

Hello All,

I wanted to share with you that I had run into the running rough and low end power loss in my 2005 xB. Thanks to you all in this forum:wink: that contributed your solutions to my problem my scion is repaired and running ever so smoothly again. At first noticing the problem while driving in town I was worried at first large costly repair bills here we come.:no: Thanks to this forum I was able to troubleshoot the problem with codes from the computer code reader that Cylinder 1 was misfiring. At first I checked and changed plugs just for good measure and small indications on them needing too. I also changed the coil pack of cylinder 1 and bang that was it. I also ordered 3 other coil packs just to have on hand or should I replace all at once or maybe pairs or just leave it alone? Any recommendations?
Thank you all again for this great forum and the great folks contributing.

Cylinder 1 Misfire
 

My girl friend's XA had the same problem. As background I have 40+ years background in auto repair and a degree in the field. First it is not a head gasket issue, the water is clear or a little dirty but has no coolant smell. After cleaning the spark plug well and having the problem return a few days later, I looked at it in the day light. Rain water (home is Portland, OR) is getting past the opening in the engine cover around the oil cap, my guess is the seal from the cowl to hood is weak, I have sealed the cap to cover area with some clear packing tape to make a water tight tent "Over Troubled Waters". I will test for a couple of weeks and report back. 10 cent fix. Make sure to dry the plug well and not drive the car with the MIL flashing, the miss can hurt the Cat Converter or cause a coil to fail. Enjoy.

Plugs changed, coils good,# 3 still misfiring, next step is to change the injectors and send it for cleaning how do I take it out???

Thank,
Rick

I tried getting someone to clean the injector, until I figured out what a mess and headache it would be finding someone to clean it and how much it would cost. Save yourself a headache and go buy one. Replace the #3 injector and see if it does it again.

As far as how to remove the injector, it would take me forever to type. I used a scion repair Manuel to walk me through it.

Rubber boot
 

My xb was misfiring, turns out the rubber piece that fits on top of the plug had a tear in it. I replaced it ($7.50) and the problem has been completely eliminated.

cylinder 1 blew
 

i'm afraid to ask but my 05 xA made a loud noise while i was driving on the freeway, which made idle like it was going to stall. there was an obvious lost of power and idle was unstable like it was goin to stall. i was still able to drive but at the same was scared. i eventually made it home to discover that my valve cover was cracked. as i removed the cover, i noticed right away that the cyclinder boot blown off and out the spark plug well. my car was making this ticking noise before it blew, i wasnt sure what it was since it was the first time i heard it. as far as i can see, the well seems dry and i don't see oil or coolant. the tip of the spark plus is mangled from the explosion. i use NGK iridium plugs, and noticed the tip and medal flange is now touching but i'm assuming that was caused when it blew. i am lost for words and uncertain what to do next. please help, any advice will be useful. thx in advance.

Check the coil pack!

My 2006 box just had the 3 stooges pop up too, after weeks of telling my mechanic something was wrong. My a/c is out, been out for 2 months, mechanic doesn't know what's wrong, then the transmission has been funky for several weeks, now the lights. Took it to O'Rielly's and coded as cylinder 1 misfire. Bought spark plugs. Hoping this is all that's wrong with my beloved square mobile. Any idea what could be causing my a/c issues? I've replaced the serpentine belt twice. I'm at 140,000

Swap coil pack from another plug to check it. Cylinder 1 sometimes gets water in it from car washes, etc and shorts out. This has happened to me, especially if you have an aftermarket grill. It may be in a sort of limp mode if you have the stooges on. First thing you need is your own code reader so you can check it and more importantly to delete the codes. Buy a cheap 40 dollar one. Not specific on why you replaced the belt. If it broke due to squealing then your compressor is going out.