Spark plug diagnosis and lean condition

[YarisSedan]

The pcv hoses deterioate over time and collapse. I should have mentioned i had the same problem with my yaris. I took out my intake to clean the filter and then forgot to hook back up the pcv hose to the intake after the maf sensor. Was wondering why my gas milage was crappy and how come my acceleration was poor.

[LtNoogie]

Yah. I don't have room to put mine there because of the aFe intake. I may have to sell mine and fabricate a smaller one. I just read a thread where someone made a small one.

Thanks, Mike.

[neo3.142]

what is the best spark plugs to use? denso or accent? platinum or regular?

[LtNoogie]

For boosted Yaris, a few of us are using NGK Iridiums, heat range 7.

[largeorangefont]

Yes that color is from the additive. The plugs look ok. Are those the stock plugs?

Why are you running additive? If it is to reduce knock, stop running additive and run plugs one heat range colder.

Maybe you have a vacuum leak somewhere.

[largeorangefont]

Originally Posted by camelll

Yeah I thought the plugs looked good too, I was just curious about the color, never seen it before. Yes I am running lucas octane booster to stop the pre-ignition. Those are not the stock plugs they are ngk iridium ix 7 heat range. 2 ranges colder than stock. I am pretty sure put not positive that I don't have a vacuum leak but the car runs top notch while driving and under boost. I did not have this problem until I changed the air filter and emptied the oil catch can but this is the first time this year I tried the ac. So the only things that have changed is adding the lucas octane booster, changing the cai filter and emptying the oil catch can. The only hoses that were disconnected were the one going to and one going from the catch can. Again I am almost certain I don't have a leak. I am leaning towards the octane booster, bad 02 sensor, catalytic converter or bad maf but shit if I know what the problem is. LOL

Cean your MAF and reset your ECU and see if it keeps doing it. Do you use a oiled air filter?

[07WYarisRS]

Originally Posted by camelll

Yeah I thought the plugs looked good too, I was just curious about the color, never seen it before. Yes I am running lucas octane booster to stop the pre-ignition. Those are not the stock plugs they are ngk iridium ix 7 heat range. 2 ranges colder than stock. I am pretty sure put not positive that I don't have a vacuum leak but the car runs top notch while driving and under boost. I did not have this problem until I changed the air filter and emptied the oil catch can but this is the first time this year I tried the ac. So the only things that have changed is adding the lucas octane booster, changing the cai filter and emptying the oil catch can. The only hoses that were disconnected were the one going to and one going from the catch can. Again I am almost certain I don't have a leak. I am leaning towards the octane booster, bad 02 sensor, catalytic converter or bad maf but shit if I know what the problem is. LOL

Just reading this for the first time...
pre-ignition?
are you sure, do you know what pre-ignition is and what causes it?
I think you mean detonation?

pre-ignition is when the fuel ignites on its own because of a hot spot in the combustion chamber...
its caused by an air leak, too hot of spark plug heat range, poor cooling system circuilation/cavitation or carbon build up. if you enegine is suffereing from pre-ignition it will rev uncontrolably and try to continue to run after the key is shut off... Some people call this dieseling. When an engine sufferes from pre-ignition you can shut the key off, remove the sparkplug wires/coil wires and it will still run as long as its getting fuel.

higher compression engines or forced induction engines often suffer from detonation (KNOCK) because the compression rates are too high or the timming is too far advanced creating too much heat for the lower octane fuel

FWIW the plug color look ok but stop using Lucas in you fuel and oil
Switch to a better fuel and true synthetic oil

[kurokoma-kun]

Originally Posted by camelll

Only at idle, when the engine rpms go up and then when they go down (to about 600 rpm) is when I get the code, I confirm this with my wideband so I know I am seeing the condition.

I have had a similar wanting-to-stall/idle hunting issue (though no DTCs set) three times now: the first time right after installation, the second time after messing with the alternator connection, and the third time very recently, for no obvious reason.

The second time I had to disconnect the lower radiator hose and dropped some coolant. After adding coolant I "burped" the air from the lines... I had to repeat this twice, after which the idle hunting went away.

This most recent time I found my coolant reservoir cap slightly open and the tank nearly empty. After topping off the radiator and filling the reservoir half full, all seems well again. Not a "by the book" solution, just my experience, and easy to try.

I also tend to get low idle speed and fluctuating ignition timing, etc, every time after disconnecting the battery/resetting ECM. It just seems to take a few normal driving sessions for the system to settle.

[kurokoma-kun]

Originally Posted by camelll

I am gonna bypass the catch can and see if one of the lines is the problem. I did notice today that my vacuum line coming from the catch can going to the intake is sucking in. I know the car is in vacuum so I would expect this a little bit but the whole hose damn near sucks in. Like the hose is weak or something is plugged.

Did you replace the hoses that come with the catch tank kit with real heater hose? The one supplied with my kit is just plain weak I replaced the outflow portion and plan to replace the other as well.

[staypuft]

Originally Posted by camelll

I am gonna bypass the catch can and see if one of the lines is the problem. I did notice today that my vacuum line coming from the catch can going to the intake is sucking in. I know the car is in vacuum so I would expect this a little bit but the whole hose damn near sucks in. Like the hose is weak or something is plugged.

go to home depot and buy a 3/8 mip barbed fitting and maybe a 3/8s barb fitting. then go to autozone and get 2' 3/8s rubber hose and connect one hose to the catch can from the pcv valve going to the catch can then to the stock hose, the stock hose goes from 3/8s to 3/4 thats how i got rid of the sucked in hose effect. hope that helps

heres a pic of my old greddy catch can if you need reference

[kurokoma-kun]

Originally Posted by camelll

The car runs great while normal driving and during boosting, just at idle and it is not all the time. Only every once in awhile.

Annoying, isn't it?

Just FYI, I bought 11/32" heater hose plus a scrap of 19mm for where it hooks up to intake manifold

[kurokoma-kun]

Originally Posted by camelll

Well I just put the factory hose on and bypassed the catch can and I am still getting the lean condition. I am in the process of pulling the MAF again and try cleaning that one more time. If that don't work then the next time I get the oil changed and I will have them replace the pcv valve and then if that don't work then the only thing left to do is to start replacing 02 sensors which is probably gonna be expensive. What else can it be?

Well, based on the DTC seems about all it can be is the MAF, an air induction leak after the maf, faulty/clogged injector, ECT (coolant temp) or AF sensor issue, PCV problem, fuel pressure loss... EFI relay in fuse box is another one, seems unlikely?

I think the reason dealing with the air in the coolant lines solved my idle control problem is because the ECT is one of the things that tells the ECM to enrich fuel mixture after warmup. An air bubble screws with sensor reading and trouble is intermittant. I'm guessing my low coolant level also caused the similar problem later.

Another thought, before you go replacing sensors willy nilly, do you have any way to check their function first? Of course the dealer uses the "intelligent tester" thing, but I don't remember if Autozone or other places can also test such stuff for you

[kurokoma-kun]

Originally Posted by camelll

I don't know how toyota checks those...

I think they basically do what you did, except they spit on the finger before running it around inside the intake

dayam, $600 I hope it doesn't come to that. Dunno maybe you need some more good luck charms... anyway, you'll figger it

[kurokoma-kun]

well hot diggity dawg! good news at last

how the hell did you get a clamp on it down there? did you have to remove the TB? or do you mean you clamped the top end

[kurokoma-kun]

Originally Posted by camelll

I have a boost/vacuum gauge. The vacuum was not out of the ordinary, that is why I was so stumped.

lol, I got a boost/vac gauge from Garm ages ago Noogs, autometer ES series (same as yours?) looks like most of us went with autometer come install it for me why doncha, take your mind off your fuel injected fever dreams

congrats on tracking down that slight hissing camelll! it's interesting because I examined that same hose on my car tonight and found the stock tension clip dealie not tight at all... is it better to use the screw type clamps on vacuum hose?

[kurokoma-kun]

well thing is I suck at soldering, my hands shake for one thing cuz i'm scared of being burned, plus I tend to lose patience before the iron can hot up the wire enough to wick the solder. Thank goodness for splice clips! good enough for me