removed Throttle Body for IAC replacement then re-installed, now questions

[fenixus]

So today finally had time to unbolt the Throttle Body from wife's 5s-fe and replace the sticky IAC valve with a brand new one ... boy, that thing was dirty as hell! I'm glad I went with a new one, made the job a lot easier and faster. some pics below.

Also I almost broke 1 of the IAC screws (got away with success later) and stripped the other one almost instantly (both on firewall side of IAC), you know that feeling when you try to loosen a screw and it just slowly turns with very strong resistance not giving any sound? well I sprayed more PB Blaster and tightened it back on and then it broke free from rust ... phew ... was able to get it out normally without breaking off the head (had this bad luck on EGR valve some time ago) ... those 2 problematic screws were totally rusted!!! the other pair (valve cover side) were not that bad.

I used Home Depot hex head bolts and washers on the new IAC, screw the screws!

Now some pics.

TB removed with cables attached, there is enough slack to leave them on. Just the coolant hoses need to be unplugged of course (those are tight over there).


This is how engine and intake looked like without the TB attached:


General pic of things how I placed them for further work:


This is a close up on the TB and old IAC (separated now):


nasty isn't it? I really wonder if this thing was installed on the intake side on engine and not maybe the exhaust one? surely looks like ti was doing the EGR valve job or so


These are the old IAC screws! almost broke the rusty ones (stripped one head instantly, needed to use vice grips for removal):


This pic shows old screws compared to new Home Depot bolts and washers (M5 washers, bolts were metric M5x0.8x16mm).


Now how the things looked like after cleaning (best as I could in a parking lot with limited tools and such):


I wasn't able to fully clean the soot off the TB passage for IAC, so it still looks black after numerous deep creep spraying and brushing, there is no clogs or any kind of blockage in passageways though:


Intake manifold somewhat cleaned up inside:


New IAC valve installed on the TB:


And then I put everything back together, adjusted the stopper on kick down cable (to 0mm protrusion) and reset the ECU. it blew HUGE gigantic clouds of white smoke (carbon and deep creep burning off) and then started running great

Took it already for a test drive with both a/c off and then on, marked all internal testing complete (including Misfire test!) and everything is green COMPLETE except for EVAP which takes longer and requires a cold soak over night to get passed.

And now some questions.

1. I liberally sprayed the open intake manifold with lots of Sea Foam Deep Creep and scrubbed what I could (varnish was hard to remove) to make it look better. Could that have caused a pending P0300 in ECU?

2. I also did my best on cleaning the back of throttle plate and vacuum port openings to make sure all is smooth, some varnish stayed, but it was much better after cleaning than before. I doubt any problem comes from here, does it?

3. Used new IAC gasket and new TB gasket on re-installation.
I used some thread sealant (didn't have any locktite handy) on the 3 TB bolts as I noticed the original ones used some white stuff to lock them up, had to use a wire brush to clean them off before installing. thread sealant leaked on gasket surface and causing it to leak vacuum now? then why the code is not confirmed and only pending?

Torqued them down all to 14ft-lbs, but since I used some crap on threads they keep turning bit by bit after 14ft-lbs, so I am not sure if I should tighten them more (e.g. to 15ft-lbs) or leave them as they are.
Torque wrench clicks on 14ft-lbs, but when I keep the force applied I can still turn it a little more and so on. tried tightening many times, but I don't want to shear the heads off!

Car runs much better (idle speed is super!), but the ECU shows me a pending P0300 code.

Now am stumped if maybe I didn't tighten the TB enough? or maybe that sea foam caused random misfires (likely hehe, there was a huge cloud of white smoke on restart) ... should I wait and ignore it for now since it is only pending?

i was also thinking that maybe now since IAC is new and ECU has a better control over idle, maybe it started detecting something it couldn't tell with a sticky/faulty IAC before?

It's not the first time I see a pending P0300 on that 5s-fe, I used to see it some times, especially in hot & humid Summer like now. it never got triggered, just pending some times ...

also I stripped the bolt's thread in air hose clamp on air box side (it's almost new! replaced both of them a year ago) and cannot make it super tight anymore, could it be a problem?


Thank you for your time and invaluable opinions!

[projektvertx]

I was anxiously reading for the part where you had to remove the IAC screws. I wanted to see how much you would complain about that part Good writeup man!

[fenixus]

Thanks

geeez, man I have a serious Deja Vu now! it freaks me out. haven't you posted those words before below on of my threads in past?

Yeah, those screws are terrible, just by looking at them one can imagine how fragile they were, I was scared to shit and was using PB Blaster on them every 5 minutes and every 1/4 turn to loosen them easier

HD hex head bolts should make it easier for future

Originally Posted by projektvertx

I was anxiously reading for the part where you had to remove the IAC screws. I wanted to see how much you would complain about that part Good writeup man!

[pmesfun]

Great right up, I may clean the iacv and tb on my aunt's Solara this week. Definitely using HD bolts upon installation on both the Solara and my car when I get a new one. For cleaning I used an old toothbrush and alot of scrubbing, cleaned out the stuck carbon buildup. On the stripped hose clamp, the same thing happen to me on my Avalon, it was the clamp that secured the hose around the throttle body. My guess is all the un-screwing and re-screwing caused the bolt to bend a little and stripped the threads, mine actually broke into pieces when I tried to loosen it again, haha.

[fenixus]

yeah, use the HD bolts I described (took their sizing from some other thread), they work perfect! they are actually about 1mm shorter than original ones, so no risk of bottoming the bolt out before it holds the valve down properly. 1 washer per bolt was just enough to get things going right.

you know those air hose clamps suck big times!

I stripped bolt threads on both of them a year ago and back then replaced with new OEM ones. soon after I stripped the new one on air box side (TB side somehow is still holding up well), it's just ridiculous how fragile and soft those crap clamp bolts are... couldn't they make them of a harder metal? those are super soft aluminum bolts ... totally useless... I could bend them with my teeth easily LOL

Originally Posted by pmesfun

Great right up, I may clean the iacv and tb on my aunt's Solara this week. Definitely using HD bolts upon installation on both the Solara and my car when I get a new one. For cleaning I used an old toothbrush and alot of scrubbing, cleaned out the stuck carbon buildup. On the stripped hose clamp, the same thing happen to me on my Avalon, it was the clamp that secured the hose around the throttle body. My guess is all the un-screwing and re-screwing caused the bolt to bend a little and stripped the threads, mine actually broke into pieces when I tried to loosen it again, haha.

[pmesfun]

Kinda off-topic, but I guess its related to this thread. Last time I seafoamed the avalon was 2 years ago at 117k, but my dad made a mistake and started the car shortly after after I finished sucking the fluid through the booster hose after it stalled out and I reconnected the house. Not much smoke came out then so I think I should do it again bc I need to do an oil change next week. Does seafoam shorten the life of the spark plugs or anything else? Cause oil leaks(rear main)?

[pmesfun]

Originally Posted by fenixus

yeah, use the HD bolts I described (took their sizing from some other thread), they work perfect! they are actually about 1mm shorter than original ones, so no risk of bottoming the bolt out before it holds the valve down properly. 1 washer per bolt was just enough to get things going right.

you know those air hose clamps suck big times!

I stripped bolt threads on both of them a year ago and back then replaced with new OEM ones. soon after I stripped the new one on air box side (TB side somehow is still holding up well), it's just ridiculous how fragile and soft those crap clamp bolts are... couldn't they make them of a harder metal? those are super soft aluminum bolts ... totally useless... I could bend them with my teeth easily LOL

Good to know, always like working with hex bolts, much better grip than screws. On the clamps I think the best thing to do is make sure the bolt is straight before loosening or tightening, seems like it gets bent by from turning the ratchet and catches new threads and strips.

[envy]

Good info and clear pics. Thanks for sharing.

[hill8570]

RE the P0300...plugs are probably kinda fouled from all the deep creep and the stuff it cleaned off. Drive it like you stole it for a bit, should clear up.

[fenixus]

never heard or read of the sea foam causing a rear main seal leak ... don't scare me.

I read it can shorten the plugs life, but honestly I sea foamed both cars with both old plugs and new ones in and can't tell anything different at all. I even removed new plugs from 5s-fe (after sea foaming) and they were looking good. I think some opinions are exaggerated seriously.

Make the car sit for at least 15mins after sucking 1/3rd of a can into the intake (via brake booster port), it *should* give you tons of white smoke on re-start and actually be hard to start at first (choking). change the oil no more than 250 miles later, I usually change no more than 100 miles later and I do it the same day (yes I drive around highways for 100 miles without destination and change the oil again in the evening).

Originally Posted by pmesfun

Kinda off-topic, but I guess its related to this thread. Last time I seafoamed the avalon was 2 years ago at 117k, but my dad made a mistake and started the car shortly after after I finished sucking the fluid through the booster hose after it stalled out and I reconnected the house. Not much smoke came out then so I think I should do it again bc I need to do an oil change next week. Does seafoam shorten the life of the spark plugs or anything else? Cause oil leaks(rear main)?

[fenixus]

no probs, hope it helps!

Originally Posted by envy

Good info and clear pics. Thanks for sharing.

you think so? it's been a while since I checked on the plugs on this car. can drive like a car jacker, no probs, reminds me when I was young and stupid and drove like that all the time haha

good to know it will clear off by itself if driven hard. always wondered.

I still need to re-calibrate the throttle plate position as it was set to compensate for bad IACV in past and now I get around 950rpm in parking gear (all other settings correct when ECU plays its role, was not possible to achieve in past with a bad IAC valve), need to lower the throttle adjustment screw setting, so in Parking gear I get pretty much about same as in any driving gear (750 preferably).

Originally Posted by hill8570

RE the P0300...plugs are probably kinda fouled from all the deep creep and the stuff it cleaned off. Drive it like you stole it for a bit, should clear up.

[pmesfun]

Originally Posted by fenixus

never heard or read of the sea foam causing a rear main seal leak ... don't scare me.

I read it can shorten the plugs life, but honestly I sea foamed both cars with both old plugs and new ones in and can't tell anything different at all. I even removed new plugs from 5s-fe (after sea foaming) and they were looking good. I think some opinions are exaggerated seriously.

Make the car sit for at least 15mins after sucking 1/3rd of a can into the intake (via brake booster port), it *should* give you tons of white smoke on re-start and actually be hard to start at first (choking). change the oil no more than 250 miles later, I usually change no more than 100 miles later and I do it the same day (yes I drive around highways for 100 miles without destination and change the oil again in the evening).

Yeah me either, just wondering, my bad if I scared you. I have seafoamed my brother's truck, and the van with good results. They both run smooth. I remember the truck smoked FOREVER. I'm actually driving 95 miles on the highway and like 10 in the city next saturday so that will be a perfect time to do the seafoaming then oil change. I need to get some Mobil 1 from Walmart

[fenixus]

^hehe, no probs

good luck!

[BamZipPow]

Just as a note...the IAC gasket is swollen from solvent. If you didn't replace it...it has a chance of gitting pinched and getting coolant sucked into the intake. You might want to replace it as soon as possible.

You can see where it's not close to the groove anymore. It's about $5 from the dealership and most likely not in stock.

[BamZipPow]

Here are the part numbers...

IAC valve gasket...
22215
GASKET, THROTTLE BODY COVER
22215‑20010
CALIFORNIA SPEC
1
$4.55

Federal
22215‑74400
1
$4.31

Throttle body gasket...
22271GASKET, THROTTLE BODY22271‑74070
1$5.65