I need to pick yall's brains about a problem with my box. I have an 06 xb, and I have had very little issues with it, ever. Two years ago the infamous VSC TRAC and CK ENG lights came on. Code scans were throwing out random codes for cylinder misfires that were different every couple of days. After a huge ordeal I replaced the Evap Charcoal canister, lights went off, all was well.
But, just in time for a February inspection, the lights came back on at the end of December. This time the only code that is coming up is 303 and P303, cylinder 3 misfire. I checked and replaced the plugs with NGK (what I had in before), no dice. Swapped the coil packs around to see if the cylinder number changed, but still a 303, so packs are fine. Wiring is good. Thought maybe the system was running to lean since the old plugs were opened a smidge more than the gap should have been.... replace the upstream o2 sensor, still the same code. I have checked the gas cap, put in some Lucas in case I have a clogged fuel injector, and to the best of my knowledge I've tried all of the other things I could feasibly do myself. Surely the Evap canister shouldn't be out again already, right? I lean against that because it is giving me one solid code..... not several different ones like it did last time it was out.
Anyone have any ideas? The guys at the local auto parts store talk to me like I'm 5 because I'm a woman, so I'm hoping to get someone to just tell me what I'm up against here. I'm afraid at this point it may be an issue with the valve spring or something similar.... Don't really want to replace the engine right now, till I know that's what I have to do. Any suggestions of some tips to try would be great. Thanks guys!

FYI: Car runs great still, a little slow to start sometimes, which makes me think maybe a fuel issue somewhere? Also, MPG went from 32-34 down to 20-22. No engine mods done on this one, this is my daily driver.

 

Manifold vacuum check, then cylinder compression test. If nothing gives any clues then do cylinder leakdown test and power balance.

 

I am pretty inexperienced with engine testing. Are these things I am going to need to have done, or can I do them myself without ridiculously expensive equipment? I don't like to take my cars to shops, I tend to get ripped off if it is something I know little about... thanks-

 

I recommend taking it to the shop with good reputation. About the only thing you can do without investing into some sort of tools is spraying carb cleaner around intake manifold to check for a vacuum leak.

 

Gotcha. I'll see if those tests yield any results... Thanks!

 

Compression test:
cylinder 1:100
cylinder 2:125
cylinder 3:60
cylinder 4:200

Looks like a new motor or a new scion. Sucks-I really love my car. Also love not having car payments.

 

Is the car bucking under power? Overheating issues? Were the spark plugs white or slimy?

With a horrid compression test like that, and without those symptoms it couldnt be a leaky/blown headgasket...

If the car is burning oil, then you would have weak/bad/broken rings

Check the oil/coolant and see if they are mixing together...

If none of those check out, then you probably have a valve issue, either weak lifter or bent/broken valve... if its the latter I would suggest complete engine replacement, as you dont know where parts of what went...

Throwing these out there so that you might be able to save yourself a little on the repair...

 

No bucking, in fact the car runs as normal with the exception of the mpg going down about 10.No overheating, spark plugs still look fine, normal darkening, very slight gap increase, otherwise normal. Oil still full from last change @2500 miles ago. Doesn't appear to be burning any oil. I am leaning towards valve problems as well. So the plan is to pull the engine out and have it rebuilt. I have found a local place that will rebuild it for $1500, this sounds reasonable to me. Is that about the cost I should expect?

 

Are they going to do any machine work to the block? Wouldnt hurt to make sure the calendars are honed nicely and to deck the block to make sure everything is how it is supposed to be?

 

Could have wrong valve clearances too. May be have that inspected before taking the motor apart.

 

Yeah. not sure where you are but the company is called JIS. All they do is rebuild japanese motors. Guaranteed work etc. Seems pretty legit.

 

how many miles did you say you had on your Box Mellybiscuit?

 

Box has 80,000 miles, just shy actually. Picking up another daily to use while I pull the motor out. I've done transmissions etc on the mini trucks, never done any major messing with the box until now. Anyone done this that may know how hard this will be? I mean, I've heard the engine is really light, and should be maybe a few hours to pull, seems like it should be more extensive than that. Anyone know? I'm pretty good with mechanics, and figuring stuff out with the help of a chilton book....lol

 

Easiest way to pull the motor is to drop the K member, detach the steering linkage, remove the 4 bolts at the top of the struts, remove front bumper, remove radiator, remove bumper support... disconnect all the wiring to the engine... then jack up the car and roll the entire drivetrain forward... the engine itself weighs the better part of 200 lbs IIRC (been a while since I pulled one) but two people can easily pick one up

 

Awesome! That makes me feel a bit better about doing this. Thanks!

 

ok. Bought a new toy/daily yesterday. Ready to start pulling the engine out of the box. But low and behold.....no Chilton's or Hayne's ?!?!?! This puts a whole new spin on things. I need a full repair manual, I was hoping to find a Chilton's cuz they make everything so dang easy. Anybody have a link to a printable manual, engine replacement guide, or a walkthrough of what the hell I'm doing? I can wing it, that's how I get most stuff done, but never anything this big. I have a feeling a missed step could really screw me up....

 

http://scionlife.org/Scion_Docs/2004...pair%20Manual/

There isnt a full service manual yet, thats about as close as youll get... and with all the times that I had an engine in and out of mine I should have done a DIY...

 

wanna do it again and post the DIY? Lol- Kidding... thanks man- that should help me out. If I come up on any snags or anything weird I know where to come ask since you have done this a couple of times. Thanks a million!

 

If I still had my xB I prob would since I got it down to a science. Feel free to ask anything if needed

 

I tell ya what concerns me most. I can pretty much figure out how to pull bolts and disconnect hoses/wires. The two major concerns for me are fuel lines and the transmission. I havent really gotten into the scion yet to see how it is really put together, but I have never really messed with the fuel line at all before. I would guess I need to release fuel pressure before disconnecting the lines? And how much support is the transmission going to need without the motor? See, I'm going to use some of your knowledge before I even get to the point of really needing it.