Water in intake... throttle body or intake gasket?

[a_young240]

I have a 96' Limited 3.4L V6 auto that I replaced the head gasket on and a bunch of other things. After the head gasket was completed and we started it up, it still has white smoke coming out the exhaust.

We took out the plugs and cranked it - it has water getting into cylinders 3 and 4 (I think it's 3 & 4 - the two middle cylinders... one on each side). We thought maybe we missed a crack in the head or something, but the oil is not contaminated with coolant and milkshake-like. Taking off the intake, we're noticing that the middle two intake passages are wet all the way up to the throttle body.

I found on the other forum an old thread that has the exact issue, but they never really answer the question...

Could this be caused by an issue with an intake gasket or could it be the throttle body itself?

Thanks,

A

 

[koulee]

Water in the intake... There are coolant lines running to a section on the throttle body that could leak coolant into the intake. My first guess would be to check those lines to see if there is damage to the lines. Other than that, I don't see how water could be getting into the intake except if you were trying to cross a river, or went swimming.

 

[a_young240]

Thanks for your reply. No river crossings over here.

I saw in the other thread someone mentioned the same thing - check the lines. I will definitely check that out, but how could a damaged line to the throttle body leak coolant into the intake? Wouldn't it drip to the exterior of the engine or something along those lines?

If it was a cracked head, would there always be coolant in the oil? I drained the oil and there is definitely no coolant in there. But it was puking out white smoke still when we started the thing up... I really don't want to tear the heads off again.

 

[BrianSD_42]

Did you resurface the head?

Were there any cracks?


A good deal of head gasket issues are actually cracked head issues. Mine was.

 

[a_young240]

Thanks. Yeah, we helped it out with a thick steel block and some sandpaper over top - checked it all along with a machined straight edge and feeler gauge... looked fine. Didn't see any cracks (but they're not always visible).

But if it was a cracked head, it would have to be cracked on both sides as there is coolant getting into 1 cylinder on each side (3 & 4). Plus the oil is drained and looks fine. Strange.

 

[awpsome]

To provide more insight for a quick check on that possibility of water/coolant getting in the throttle body it's not the lines that matter, as you stated those lines are all external hoses and if they were cracked it would leak out on the engine bay and not inside the throttle body.

What you want to do is take off the throttle body and then remove the IAC module. It is held on by a few Phillips screws and take your time taking those off. Stripping them would not be fun and can make this 5 minute check into a mess

But what I am getting at is when you take off the IAC from the throttle body you will notice there is a gasket in there that separates the coolant lines from actually air coming through the IAC to the intake.

VERY IMPORTANT: buy that gasket before taking your throttle body apart from the IAC unit.
It's a gasket that looks like three irregular squares and I say this because when I took mines off to clean my IAC it was so heat warped it "grew" and oversized itself so I could not put the original one back in. So my truck was down for a day because I didn't want to "chance" it by squeezing in the gasket and having coolant leak into my intake and potentially hydro lock my truck.

But I'd check there as that's where coolant can be sucked into the intake through the throttle body. It's be the first and only place to check to get water in from there.

Your gasket may have been warped or cracked and may have a slow leak going through.

Ill see if I can find a part number and picture to show you.

 

[awpsome]

THESE are photos I took from another member on this board when he was cleaning his IAC as well.

this picture shows the IAC when removed as you can see the gasket I am talking about in the picture above the IAC unit. that gasket sits in the grooves in the IAC on the throttle body side and will prevent the coolant from entering the air line side.

this is where the IAC is mounted on the throttle body, you will need to remove the throttle body completely as it is located on the bottom.

PART NUMBER for IAC GASKET: 22215-62180
*I think, you might want to cross confirm with your Toyota dealer and make sure its the IAC to throttle body gasket

 

[a_young240]

Thanks for your insight! I actually took that apart today and looked at that exact gasket. It didn't look too cracked or worn. We even did a bit of a pressure test while it was off to 13-15lbs with a tiny bit of coolant in there - no coolant came out. Could a small leak such as this cause white exhaust?

I guess now that I opened it up I should shove a new one in there?

 

[shootmymime]

when you started it how long did you run it for? could you have just been burning off what ever was left around the cyl walls or top of the pistons. or maybe left over coolant that made its way into the exhaust and was being burned in the CAT?

oh now i remember you saying you had found traces of water up the intake to the TB.
well just a thought if you hadnt run it long enough to burn all existing spilled coolant out. good luck.

 

[a_young240]

That's exactly what I was hoping. I put insurance on the thing and drove it around for 2 days keeping a close eye on fluid levels.

In the end it was still shootin' out white smoke and coolant levels were dropping.

 

[Kurtis]

That's exactly what I was hoping. I put insurance on the thing and drove it around for 2 days keeping a close eye on fluid levels.

In the end it was still shootin' out white smoke and coolant levels were dropping.

I don't think the gasket is a likely culprit. If it was faulty, I would think it would make more cylinders wet with water than just number 2 and 3. I would start considering a crack in the head or the head gasket. It's more likely since they are right next to each other. It could be cracked in a way that does not contaminate your oil with coolant. Maybe the coolant is being burnt off before that happens. Sorry about the truck though. I hope you get it figured out with minimal ass pain.