CHRRRIS

So lately (last two weeks) my Z28 has had the weird VATS issue twice, I waited for the security light to go off then it started fine. It happened on two separate occasions and has worked fine in between and since then. The last time I drove it was two days ago, just a small ride got gas then parked it at my house.

Today I get in to start it up and it starts to turn then stops itself, appearing to be a VATS issue. The light never came on though so I went to start it again and the motor immediately shoots to 2000rpm's, I quickly think for a second then shut it off.

Upon inspection, there is a small puddle under the passenger side header collector, smells like gasoline.

Under the hood nothing jumps out at me other than some liquid around the second injector back on the passenger side. It is only a very small amount. It doesn't smell like anything though... ? I wouldn't know if it wasn't just water.

The puddle under the car is much further back than where the injector is so I do not know if they are related, plus only the liquid under the car smells like gas.

I am thinking the puddle under the car might be sneaking through a pipe's weld connected to the collector... but is the liquid that comes out of your exhaust on cold start up smell like gas? I've never thought about it until now.

Also since I did a vague search just now, I saw something about an IAC valve on the throttle body. I went back out and do see a metal nipple-like pipe coming off my TB with nothing connected to it. I couldn't find anything that appeared to be disconnected from it though, does anyone have any ideas about this?

Please help me out guys, I am away at school and any mechanics I've ever used so I don't want to tow it directly to some random shop. I am also worried to start it up again until I get an idea of what to look for.

Thanks in advance

LS-1Z28

iTrader: (6)

well good news... you're engine isn't going to blow up.

However, you will want to find out where the tube from the throttle body has gone. If it's the one on the passenger side it should have a tube running to the passenger valve cover.

Also, the liquid around the injector is probably only water. When it rains water can pass through the wiper shroud and fall onto the intake and make its way to the injectors. It shouldn't hurt anything though since everything is sealed off (o-rings, gaskets... etc).

As for the leak under the car. You might want to get under there and find out where exactly it is leaking.

osuhog

iTrader: (16)

I don't know about the puddle & everything, but the really high/sticky idle could definitely be the IAC valve. I had that problem once & it was just the valve sticking. It is very easy to remove & clean, so if I were you I'd go ahead & do it just to mark one more thing off the list.

The IAC valve is on the drivers side of the throttle body. I have it labeled in the pic below & arrows pointing to the screws you need to remove to get it out. I believe they are T20 torx heads. Also, you will have to unplug the wiring plug which isn't shown in this pic, but is very self explainatory.

After you unscrew the screws, be careful removing the IAC. You might have to tug on it a bit to get it out, & make sure to not drop the o-ring. It's kind of a plunger type deal. So, get it out & shoot the rubber like end off real good with some MAF cleaner or carb cleaner & wipe it good & let it dry & reinstall it. That black plunger tip gets really sticky, so that was my problem. Probably wouldn't hurt to spray inside the hole before you reinstall the IAC valve & make sure it's good & clean too.

CHRRRIS

Ok went out and checked everything out again.

1. The little puddle by the injector appears to just be rain water, it's raining now actually and I could see how it trickles down to that area.

2. AIR and EGR were both removed from the car when I got it. I could not find anything that could connect to the metal tube coming out of the passenger side of the throttle body. I am guessing it is due to the AIR and EGR being gone.

3. After a bit more research, I am self diagnosing my problem as a sticky IAC valve. I think the VATS issue may be due to a bad battery or terminals, as it is an older battery and my security system has been acting funny lately too. When I go to lock it it only beeps once then 30 seconds later will set off the panic until I hit lock again.

The puddle under my passenger collector still has me dumbfounded. I need to know if the liquid that comes out of your exhaust when you start it should smell like gas or not. I recently had my bullets dumped directly off my collectors, and I'm thinking since then they may have slipped off a bit or there may be a bad weld leaking some of that liquid through and when my car started turning 2000RPM's on cold start up it forced a good amount through creating the puddle.

Anyone know?

I will attempt to take off and clean the IAC valve this weekend. Is it a bad idea to try starting my car again before I figure out where the possible gas puddle under the header is from?

joecar

The puddle under the collector is condensation that accumulates in the exhaust as engine cool down... run your fingers thru the puddle, it's water, it might have some gasoline in it due to startup enrichment.

osuhog

iTrader: (16)

I just went out & snapped a quick cell pic of the passenger side of my TB. Is the place where I marked 1 or 2 where you have a pipe coming off with nothing connected? If it's #1, you need something there. If it's #2, don't worry, that's just a throttle body bypass.

CHRRRIS

joecar - thanks for the info, might just be a bad weld in my exhaust then.

osuhog - #1

NHRAFORMULA00

iTrader: (2)

if its number 1,that will cause a high idle.

CHRRRIS

Well I don't have AIR or EGR, would that be the reason?

I honestly don't see anything where a tube would connect it to. I have no idea what would have happened to the tube even since the car hasn't moved since I drove it last, and it drove fine then.

osuhog

iTrader: (16)

Yikes, you have a huge vacuum leak! There should be a big hose that connects straight from there to the valve cover, as shown in this pic I attached. I don't have air or EGR either. That hose isn't either.

Someone correct me if I'm wrong, but I don't know how the heck you're car has even been drivable without this hose??? The only thing I can think is maybe it just disinigrated (sp?). As you can see, I had to rig up the pcv hose on my car as it basically did just that, although it was still in the engine compartment at least.

CHRRRIS

Well that's pretty scary. I wonder where the heck the hose went since it was last driving perfectly fine. Gonna look into it tomorrow, no garage and it's dark outside.

armyboyatc

iTrader: (29)

Well the hose could've just fallen off, worst case scenario you just go get a piece of hose from your local auto parts store and replace it.

CHRRRIS

Ok so I don't think I ever had a hose that connects those two tubes. I snapped some pics and will upload them now.

There was a rubber cover over the tube on the passenger valve cover, but nothing covering the tube on the TB. The rubber cover on the valve cover tube was all torn up and had cracks in it.

I removed it but now my question is, should I get another cover just like it for only the valve cover tube, or should I get a long hose to connect the two? Like I said my car ran fine before yesterday, so my guess is that there never was the hose, only a rubber cover on the valve cover tube.

What do you guys think?

*Uploading pics now.

CHRRRIS

bene

iTrader: (16)

You need to buy two caps, one for the deteriorated cap at the valve cover and one for your TB.

osuhog

iTrader: (16)

I bet the cap that was on there just ended up deteriorating & falling off on the ground somewhere. I believe the hose that was there from the factory is a crankcase ventilation deal. Obviously the way you have it was working before, but I'm not sure what kind of trouble you might have in the long run by running it capped. Anybody else?

CHRRRIS

So I got some new caps, put 'em on and it seems to be running like normal.

There was a ton of condensation / some clear liquid that came out of the passenger side muffler though, and only the passenger side, not the driver side. Weird, but I let it run for a few minutes and it stopped spewing any liquid.

osuhog - thanks a ton for the pictures. and thanks everyone for all the advice, LS1tech is awesome because of people like you.

LS-1Z28

iTrader: (6)

it looks like the previous owner has replaced the pcv system for a breather.. he should be ok but if it were me I'd run the stock pcv with a catch can.

osuhog

iTrader: (16)

I have used so much info from this site & had so much help from various members, glad to finally be on the other side for once.

Good luck man!