84z28h.o.

Well today was a total waste of 11 hours. I flushed the radiator, took the thermostat housing off....upon doing so, one of the bolts was so rusted that the head broke straight off of it.

I could not get it out for the life of me. Tried everything in the book...except for drilling it out completely and re-threading the hole. Vice grips didn't work, used a hell of a lot of PB Blaster...

Changed the thermostat out though, hooked up a new temp gauge and I caked on some RTV compound around the thermostat housing...leaked a bit, but nothing major.

Car smoked, which I am assuming the oil has gone bad since it overheated yesterday....going to change the oil tomorrow. The idle is off....it was up at 2000 - 2250 and I found that the throttle was sticking a bit near the carb, so I got that taken care of. Then the car wants to idle around 750, which I thought was damn perfect....it'll shoot up to 1500 or so, and stay for a while. The car has hesitations when driving, and a few second "delay" when at full throttle.

The temp was around 180 and then would climb to about 200....at one point it got up to 230 and I pulled over and shut the car off for a bit, and it went down to 190 and I went on my way. Got the car to my house and it was at 200...parked it and haven't started it up since.

It leaked a bit of antifreeze when I parked it....I am assuming it lost a good amount while driving.

Now, I am sure that once I get that bolt out of the head (at the thermostat housing) and replace it, the leak will go away....because that is the only place it is leaking from. I checked all the hoses, the radiator, etc. and there are no leaks. The coolant will run to the back of the engine and down, as well as to the front and down. But it is only leaking at the thermostat housing.

What I'm not sure about is the idle....I was thinking, maybe since the seal isn't good at all at the thermostat housing, the engine was losing pressure inside...or vacuum...or something. Which is very plausible. I've adjusted the idle screw, and it was idling between 750 and 1000 when I first did the flush and fill, etc.

I also cleaned the carb up and used seafoam in the carb....which I used seafoam on my other (now wrecked) car and it worked great...same white smoke came out of the exhaust, but that went away after a few minutes.

But any input would be appreciated. I'm just not sure if the leak at the thermostat housing would cause that hesitation and weird idle.

RITTER

iTrader: (5)

The cooling system will not affect your vaccuum or any type of pressure inside your engine. The pressure inside the cooling system stays in the cooling system. The cooling system could lose a lot of pressure by not having one of the thermostat housing bolt.

84z28h.o.

Hmmm...I was thinking maybe it could affect the pressure since the coolant flows through the engine and whatnot.

When I bought the car, the vacuum hoses going from the air cleaner to the engine were cut and they plugged them up with SCREWS. I put new hoses on the air cleaner and connected it to the engine where there are nipples in front of the carb. There was another nipple - plastic - and an extra nipple near the carb (the two near the carb are actually joined together...kind of an L shape) so I connected those two together.

It idled fine when I got the car...the hoses were plugged and whatnot. Then last night it started taking a huge crap on me. Engine kept dieing so I had to start it back up at every light or stop I made....if I gave it gas, it would stay running. Push the clutch in, I'd have to be quick to get on the gas again...if I was braking it was a pain in the ***.

So I am not sure what is up with it.

RITTER

iTrader: (5)

Well all the cooling pressure stays in the engine water jackets and radiator and whatnot.

You might want to find a vucuum routing diagram and make sure that all your vacuum lines are running correctly.

It also sounds like you hae some more serious carb issues. What type of carb are you running?

84z28h.o.

It is a 4 barrel carb...I believe it is stock.

cheppibear

The SES (check engine) light should have come on if the CTS sensor plug was disconnected. Make sure this is hooked up.

If the vacuum hose for the EFE is not plugged into the port in the theromstat housing you should not have driveability and idle problems, but you should check the operation of your EFE valve. If the EFE valve in the exhaust manifold collector is stuck in the slightly closed position where it would be on initial start up to help warm the car up, it could be causing you the idle, driveability, and potentially overheating problems. THe exhaust simply can't get out of the manifold on the one side and that could be choking the motor causing it not to breath.

84z28h.o.

Check engine light does not come on immediately. It came on earlier when I went down the street...the temp gauge shot up to 240 and it came on. I'm going to plug that sensor back in tomorrow.

Where is the EFE in the exhaust manifold?

Jproz1167

iTrader: (3)

with no vacumn the efe valve just stays open, however I guess it could have stuck closed maybe.

sounds to be like the choke is staying closed and thats whats causing that high of an idle. I would think it woiuld take a hell of a vacumn leak to cause the motor to idle at 2,000rpm.

naf

iTrader: (7)

What sensor? Fix your thermostat housing first. Your Coolant Temp Sensor plugs in there and a leak could be causing an erratic temp reading telling the ecm to go in and out of closed loop. Fix what's broke first. Then check your codes.

Don't worry about the EFE. Even if stuck closed, which is unlikely, it shouldn't affect idle although it could cause a problem at higher rpm.

86NiteRider

iTrader: (10)

I did the same thing to my thermo housing two years ago. I sucked at drilling it out (ruined the intake) and I even tried like you to run the car with one housing bolt. Not good as the temp still shot up and the car leaked right where the bolt broke and I had tried to drill. That meant I had a pressure leak because I had a water leak. Finally I gave up and put a new intake on and then a new housing for the thermo and everything went back to operating the way it was suspose to. There just was no way around it and I came to this conclusion after playing with it for a week. I am scared to death next time I have to take that thermo housing off but every now and then I give those two bolts a shot of PB Blast just in case.

Fix the thermo housing problem first because if you don't you will always have a leak and a problem. There is no getting around it.