Just cleaned my MAF and Throttle body, I4, no fun, now I need parts!

[HotRod53]

My I4 has 93K, so I figured that it was time to clean the MAF and throttle body, it had been idling rough at a light, that and mileage sucks. I went out and bought MAF cleaner and TB cleaner both from CRC.

I started to disassemble, kind of a PITA, removed the air cleaner lid, it has 2-3 connectors and a retainer strap plus a hose to take off. I took the screws out of the MAF and cleaned it while in my hand, can't really do it while in the tube because you can't get to the other side. Now is when the fun started!

Remove the plastic tube looking thing on top, no big deal. You can't get to the clamp for the snorkel connected to the TB without first removing the intake resonator. NOTICE .... never twist the intake resonator, it has a vacuum tube connected to it that you can't see, the plastic tit SNAPS RIGHT OFF! Yes that's right, I broke it right off and no one has one in stock!

Looking down in the TB, yep, it needs cleaned. The butterfly isn't bad, but there is a brass looking honeycomb on the upper part of the throat that is just black and covered in oily looking crap. I sprayed away and even toothbrushed what I could reach. Access if difficult, it is a foot below the head between the firewall and the motor.

I had a rubber handled pair of pliers that I stuck in the throat to keep the butterfly open while cleaning, not an easy job being way down in the back like that.

Currently I'm waiting for the JB weld to dry so I can reassemble. I ordered a new resonator but being Saturday, I won't have it until Tuesday! I hope this was all worth it!

[HotRod53]

UPDATE: so the JB Weld appears to have done the temporary trick, new part due on Tuesday. I got it together and started it up, it was difficult to start as you can imagine after all that spray going in the TB. It choked and spuddered and eventually smoother out normally.

I took it for a ride and here are the differences; my in Drive stopped at a light idle before was 750 RPM, it is now 1100 RPM. My put it in Park idle is now about 1700 RPM.

It seems to be as if it is now idling too fast, maybe the computer had to adjust to clean MAF and TB??

[fatngs]

Originally Posted by HotRod53

I took it for a ride and here are the differences; my in Drive stopped at a light idle before was 750 RPM, it is now 1100 RPM. My put it in Park idle is now about 1700 RPM.

It seems to be as if it is now idling too fast, maybe the computer had to adjust to clean MAF and TB??

probly..... personally i would disconnect the battery for about an hour or so so the computer can relearn how to idle correctly after cleaning the MAF & TB

[HotRod53]

My battery terminals neeed cleaned anyway, going to pull them, clean them, install those red and green pads. reinstall, and seal with spray.

I've driven about 20 miles and it's still not reset, I can see a marked degradation in fuel mileage becasue of the fast idle. The I4 mileage sucks anyway, none to waste.

[hardtopte72]

When you cleaned the throttle body with the pliers was the vehicle in the ON position? If so you may have damaged the inside of the throttle body. Usually the car relearning does exactly what you say but should go away after around 10-20 mins.

I never remove the resonator. The way I do it (For all 02-09 Camrys with DBW throttle)

1. Loosen 2 10mm bolts holding air box cover.
2. Remove the 2 10mm bolts holding the coil cover (I don't remember doing this on all but I think some 2AZFE like tC's need this)
3. Remove the MAF sensor connector.
4. Remove the one evap hose that connects all the way to the nipple on the throttle body (pull straight down) and remove the hose that connects to the PCV valve.
5. With a long pair of needle nose pliers compress the spring clamp and lock the two pieces together (may take a few tries)
6. Remove the entire air intake hose assembly and set it to the side
7. With a gloved hand and the vehicle completely OFF open the throttle plate with your hand and spray throttle cleaner.
8. Using a toothbrush clean all the carbon from around the throttle body and from the top and bottom of the plate. Clean as far down into the intake as the toothbrush will reach. Alternate between spraying the toothbrush to clean the carbon from the bristles and spraying a small amount of throttle cleaner down the throttle body to wash away the carbon.
9. Remove your hand and let the throttle close
10. Reinstalll the intake hose on the throttle body and position it correctly to line up the airbox.
11. Reinstall all hoses in their respective locations.
12. Unlock the spring clamp and make sure it is not uneven or out of place
13. Tighten the airbox bolts and reinstall the engine cover.
14. Now I remove and clean the MAF sensor.

[HotRod53]

My key was not ON when I held the TB open with the handle of the pliers. I used these pliers because they had a really thick rubber padded handle, I used the handle part to hold the butterfly open. This kept anything from having a metal to metal contact.

I was unable to get to the snorkle clamp with the resonator in there, maybe I could now that I know what everything looks like down there. The resonator having never been removed for 93K was stuck in the rubber. Had I known it needed pulled straight out, I may not have broken it. I tried to twist it to get it loose in the rubber snorkle, therefore snapping that 1/4" tit that goes in the fitting.

After removing the battery for 10 minutes, and the terminals needed to be cleaned anyway, my idle went back to normal. My idle is somewhat smoother, yet not as smooth as I think that it should be. It could just be a characteristic of a 4 banger, this is my first one.

I can however say that yesterday I did a 130 mile trip and received 3 MPG better than my recent 250 mile trip! 28.1 MPG vs 31.0 MPG according to the dash, which I know is not accurate. Any way you look at it, its almost a 3 MPG gain in comparrison. I know that my mileage would have continued to increase had I kept driving.

[jbrnigan]

With all the advice, instructions etc, given on this thread, the ONE piece of advice I will share is: DISCONNECT THE BATTERY - BEFORE - doing any work on anything connected with the vehicle electronics.

[hardtopte72]

To be honest on something like this simply having the vehicle off will suffice. I have done 100's of induction services of Camry's and never removed the battery or had an issue (removing the battery would mean redoing the clock and presets and I am too lazy for that )

[jbrnigan]

Originally Posted by hardtopte72

To be honest on something like this simply having the vehicle off will suffice. I have done 100's of induction services of Camry's and never removed the battery or had an issue (removing the battery would mean redoing the clock and presets and I am too lazy for that )

You are right (I didn't say REMOVE the battery), just disconnect it! Yep, your radio presets and clock will be lost. I will just say that a disconnected battery will ELIMINATE even the remote possibility of an errant electrical transient, on purpose or by accident. Anyone that has spent any time in the vehicle maintenance arena has probably experienced the cascade of problems that can be caused by a "spark". (From a blown fuse to a major component failure). But, you don't NEED to.

[HotRod53]

They make a cheapie plug in device that you put in your cigarette lighter or accessory plug for those of us who hate to re-do the radio stations.

[leakyseals]

Its a DBW throttle body, so its not that easy to clean. No throttle cable, all electronic, the best way is removal. The way I clean the DBW TB is key on, have somebody step on the accelerator. Or pin the accelerator with wood. Jamming the plates open manually has been known to strip the electric motor requiring a TB replacement. Hope you see this message before something bad happens.

[hardtopte72]

Originally Posted by leakyseals

Its a DBW throttle body, so its not that easy to clean. No throttle cable, all electronic, the best way is removal. The way I clean the DBW TB is key on, have somebody step on the accelerator. Or pin the accelerator with wood. Jamming the plates open manually has been known to strip the electric motor requiring a TB replacement. Hope you see this message before something bad happens.

This is if you jam it open with KEY on. Which is why I asked that in the first place. If you took the throttle body completely off you would still need to manually open it to clean it properly.

And yea I knew I would take heat for the battery (I didn't literally mean remove the whole battery just the negative) but I am going off my 100% no issue track record ( I just can't imagine how with key off and cleaning the throttle body you could get any sort of spark) with my way of doing it.

[jbrnigan]

Originally Posted by hardtopte72

This is if you jam it open with KEY on. Which is why I asked that in the first place. If you took the throttle body completely off you would still need to manually open it to clean it properly.

And yea I knew I would take heat for the battery (I didn't literally mean remove the whole battery just the negative) but I am going off my 100% no issue track record ( I just can't imagine how with key off and cleaning the throttle body you could get any sort of spark) with my way of doing it.

Again I say - "Yer Right" - "No Heat" intended. If HotRod53 knew what you know, this post would have never happened. Since most posts to this forum looking for a "now what" solution come from folks that don't know what you or I know, I error on the side "basics". Your 100% track record didn't come (or maybe it did) by accident, multiple, similar repairs is called experience. A lot of the folks asking for repair advice on this forum don't have that experience and could be better served by responding to them at their level of understanding. "A wise man knows everything that he doesn"t know".