STUMPED...rough idle and hesitation
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STUMPED...rough idle and hesitation
So here's the deal...I just bought a 84 Z28 high output not too long ago. It has an electric fan that's hooked to a toggle. I ride with the fan on....that's what the seller told me to do.
Well, all isn't too swell. The coolant reservoir was pretty much dry as a bone, with barely any fluid at the bottom of it. The car started smoking so bad today....put coolant in and it boiled out of the reservior.
Got the car to my buddy's house...we took the radiator cap off and there was no fluid inside...and it is a brownish color, as well as in the reservoir. Which I am assuming is rust/scale.
Put some coolant into the radiator...all the way to the neck and turned the car on. The coolant got sucked up. Idle is very low....500rpm. The battery gauge was right at 13v when it was previously up probably about 15/16. I drive the car a bit....idle goes back to normal and the battery is up. THEN the car goes back to low idle and if the gas isn't pressed, the engine dies. Can't restart it unless I push the gas at the same time. Can this be caused by overheating??
I drive the car back to his house....have to start the car up at every stoplight or any time I have to stop.
Well...now 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.
The vacuum hoses from the air cleaner to the engine (right in front of the carb) were all cut and plugged by SCREWS. I changed the hoses out and connected them. There were two metal nipples in front of the carb and one plastic one a bit farther forward....plugged the plastic one into one of the metal ones and the air cleaner into the metal one. I was thinking maybe that causes it to idle weird and hesitate, but I'm not sure....since the fact that it ran completely fine earlier in the day yesterday and then started acting weird.
I really don't know what's up with it...my thought was the coolant, since it overheated and then would die when it was just idling. But today, after flushing the system and everything, it died one or two times. I'm thrown for a loop....maybe one of you will be able to help me out more.
Well, all isn't too swell. The coolant reservoir was pretty much dry as a bone, with barely any fluid at the bottom of it. The car started smoking so bad today....put coolant in and it boiled out of the reservior.
Got the car to my buddy's house...we took the radiator cap off and there was no fluid inside...and it is a brownish color, as well as in the reservoir. Which I am assuming is rust/scale.
Put some coolant into the radiator...all the way to the neck and turned the car on. The coolant got sucked up. Idle is very low....500rpm. The battery gauge was right at 13v when it was previously up probably about 15/16. I drive the car a bit....idle goes back to normal and the battery is up. THEN the car goes back to low idle and if the gas isn't pressed, the engine dies. Can't restart it unless I push the gas at the same time. Can this be caused by overheating??
I drive the car back to his house....have to start the car up at every stoplight or any time I have to stop.
Well...now 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.
The vacuum hoses from the air cleaner to the engine (right in front of the carb) were all cut and plugged by SCREWS. I changed the hoses out and connected them. There were two metal nipples in front of the carb and one plastic one a bit farther forward....plugged the plastic one into one of the metal ones and the air cleaner into the metal one. I was thinking maybe that causes it to idle weird and hesitate, but I'm not sure....since the fact that it ran completely fine earlier in the day yesterday and then started acting weird.
I really don't know what's up with it...my thought was the coolant, since it overheated and then would die when it was just idling. But today, after flushing the system and everything, it died one or two times. I'm thrown for a loop....maybe one of you will be able to help me out more.
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