JCPBlackBox

2006 Scion xB - stock, no mods, 50K miles, daily commuter vehicle, no problems for 4 yrs...

so three weeks ago, my box starts shuddering and bucking all of the sudden. 25% loss in power, and it sounds like a go-cart when I accelerate. The "three stooges" came on, and it coded a "cylinder 1 misfire". I jumped online to see if I can get ideas on how to go about fixing the problem because I refuse to take it to the dealer. The main solutions I keep reading about are the 1)plugs and 2)coil packs.

As of now I have changed the plugs (all the old ones looked fine but I changed them anyway), and swapped the #1 and the #4 coil pack to see if I could get it to code for a different cylinder.... And it continues to code for #1 cylinder.

I also read that it could possibly be a fuel injector, and I might try putting a new one on the #1 just to cover all the bases. Compression test results hopefully will be updated soon (going to try to do it tonight).

This problem seems to be seriously frustrating for a bunch of people, and I rarely see a resolution to the forum posts on this topic. So I'm not the most mechanically inclined person, and I love my box, but the problem comes and goes. It will be fine one second and sputtering the next, and it will be great for a day or two and then start up again. Just when I think I've solved the problem it starts again. This is the family Box and I want to fix it before my wife decides she wants to trade it in. ;^) I could use any suggestions or advise.

Help me Scion family....your my only hope.

JCPBlackBox

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?

Reactor

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

JCPBlackBox

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.

boilermakertommy

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

JCPBlackBox

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.

Reactor

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

JCPBlackBox

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.

JCPBlackBox

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.

jpn6438

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.

RichBinAZ

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.

Daguy

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.

torranosaurus

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!

jpn6438

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.

mdtjr

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.

torranosaurus

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

torranosaurus

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.

jpn6438

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.

torranosaurus

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

JCPBlackBox

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.