Idle Quality - Low To High When During Cold Temperatures

dom

04 Corolla CE 5spd
No need to disconnect any coolant hose, even on the TB which can be cleaned and set aside on top of tranny with the two coolant hoses still attached... I would probably use a blunt flexible scraper. Whatever you use, have it at a very low angle, without digging into the aluminum. Carefully slide on it at nearly the same angle as the surface you're cleaning. Finish with a green scrubbing pad used for dishes, along with warm water and dish cleaning detergent, or similar, then wipe it off.

If you have time and before you even try scrapping it, let it soak submerged in scolding hot water with dish detergent for a while, then use only the green scrubbing pad. Rinse out under running water, then wipe dry.

After removing manifold and before cleaning the head seating surface, carefully wipe out intake port inlets and stick a clean rag or paper towel tightly in each opening to keep any debris out... Remove just before reinstalling clean manifold with new gasket.

 
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autotech2612

New member
Found that ground point on the body (last photo). In the photo, it seems near impossible to get it out of there without draining the coolant and moving the radiator hose out of the way. I've taken photos of bolts I assume I have to remove, include the two down at the throttle body? Gasket comes in tomorrow, not today as the woman at AAP stated.











 

dom

04 Corolla CE 5spd
Yes, that's right about the bolts. You also need to disconnect vacuum and PCV hoses and sensors from the throttle body and unbolt it from manifold. You can also unbolt throttle cable holder from throttle body. End of throttle cable can be unhooked in wide open throttle position... It'll be more obvious as you go.

I see that body ground. You just need to remove the airbox to access it.

 
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autotech2612

New member
I figured it'd be more obvious. Tomorrow is the big day.

So, do you recommend I just drain the coolant and pull that upper coolant hose back to make it easier?

Update on another ECT sensor (same brand installed today): Now the needle on the gauge moves as it should -- quicker -- and in 42-degree weather.

However, with this sensor, the needle is a little above the halfway point.

Just shows each sensor usually yields either a slightly different result or a major difference.

Idle issue is still rather high when starting out (back up 2000 RPM).

Both sensors were installed after the ground point wires on the engine were cleaned using the wire brush.

Yes, I will have to take the air box off. Pretty easy.

Really looking forward to the Toyota sensor. I'd be surprised if nothing changes.

 

dom

04 Corolla CE 5spd
I would not bother with the coolant hose or with any coolant draining... I see now that it's hard to look behind 8th gen manifold flange to witness any signs of leaking.

 

autotech2612

New member
Intake gasket looked great, looked just as good as the new one. Someone may have replaced it before I bought the car. Replaced it anyway. Did have to remove the upper coolant hose; there's no way to fully move the intake away unless the hose is gone. Reclaimed the coolant. Found another ground wire under the air filter box. Cleaned. Oh, and I noticed the VSV at the air filter box may have been disconnected for awhile. Perhaps this past summer? Maybe this caused the erratic and unusually high idle when cold out. I re-inserted it.

Did my best to clean the intake, but it's pretty bad. There is sand, oil and sludge. Not sure what in the hell the previous owner did. With all that sand, it's as if the car didn't have an air filter installed for awhile. I'm very surprised I am not burning more than 1/3 quart of oil every 3,000 miles, and surprised I don't have any lifter noise.

















 
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autotech2612

New member
Update: no change in idle quality with VSV re-attached to air filter housing. With this ECT sensor, the idle is always at least 1100 RPM, even when gauge is mid-point at 53 degrees Fahrenheit. At a stop light, it does resort to 800 RPM within 20 seconds.

As originally stated, each ECT sensor yields different results.

The finger re-points to the ECT sensor.

 
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dom

04 Corolla CE 5spd
I can see evidence of leaking at your old intake manifold gasket... How is it running now that the ECM had a chance to relearn the operating conditions?

 

autotech2612

New member
No change at all.

However, as of two days ago, I hear a foghorn or like the sound of a smoke alarm beep (the tone) coming from the LF of the top of the valve cover. I thought it might be injector-related, so I unplugged the connector, but the noise remained.

All I did was take the old gasket off and put a new one on. Was I supposed to use a sealant? I'm wondering if there is a leak.

I paid on 11/07 for the ECT. However, they didn't ship it out until last Wednesday and I'm not expected to receive it until mid to late next week. They did give a 15-percent discount for the inconvenience.

Temps have been between 20 and 35 degrees. Doesn't idle wildly in the garage like it was, but still idles very high when I get to the stop sign after leaving home.

Just need to focus on this noise in the meantime. . .

 

dom

04 Corolla CE 5spd
No sealant was required. Intake manifold is torqued to 23 ft-lbs on my 2004.

Make sure you hooked up all hoses back on, including the elusive brake booster vacuum hose on the rear of intake manifold near throttle body... Are you now hearing the VSV operating now that it's hooked up?

 
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autotech2612

New member
No, I'm hearing it from the right-hand side of the valve cover.

I am going to take the entire thing off and use a pad to get any other remaining gasket material off. However, this gasket is metal. So, there really shouldn't be any real material there, right?

Brake booster hose? Going to the garage to check it out now.

 

autotech2612

New member
Also, how do I get the cable throttle cable off from the throttle body? Just remove the bolt in the center of that wheel?

 
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dom

04 Corolla CE 5spd
Right hand side when you're looking at it (driver's side) ? Is that where your PCV valve is?

Is the gasket not rubber coated metal? Did you not clean the sealing surface on manifold and engine head before installing new gasket?

The throttle cable end barrel can be slipped out sideways while rotating the throttle cam by hand to full throttle position to have cable slack.

 
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autotech2612

New member
Thanks for the reply, dom.

The PCV on mine is on the left-side (driver's side). But, if you're looking at the engine in front, that would be the right side.

I don't believe the gasket is rubber-coated metal. I did not clean the sealing surface. That's my mistake.

It will be best to take it off again and fully clean. I can take it all out with the throttle body still attached I assume. Just have to disconnect some wiring and hoses and you previously stated.

 

dom

04 Corolla CE 5spd
It should simply have been done properly the first time. I thought I had sufficiently stressed the importance of cleanliness upon reassembly... The metal gasket is black because it has a rubber coating. It's visibly not bare metal. At any rate, it may now possibly be compromised, and a new gasket would be advisable to replace it again successfully.

 
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autotech2612

New member
I think the gasket will be fine. I am taking it apart after work today. Will update and post photos.

What do you think I should do about all the sand, sludge, oil in the intake manifold and the area where it enters the engine? An acetone or mineral spirits soak?

I plan on using plastic grocery bags to stuff into the ports while I use a scouring pad to clean any miniscule gasket material off. Really, there is very miniscule residue.

 
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fishexpo101

I know Karate, Kung Fu, and 47 other dangerous wor
Not sure if acetone will do anything with that stuff. Mineral spirit soaking might be better. Berryman B-12 Chemtool has some pretty strong solvents in it - works great on cleaning parts. But will eat aluminum parts, if left to soak for an extended period of time. But scrubbing with a parts brush / old toothbrush - should be fine.

But those deposits did look pretty gnarly - might have to mechanically scrub them out - fiber cross-buffs or similar might be needed.

 

autotech2612

New member
Coolant temperature sensor -- which according to FedEx was supposed to arrive on 11/21 -- arrived today.



 
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