i hope the bang you heard wasnt hydro lock.
HELP! Engine turns over --won't start?
Thread Starter
Burning Brakes
Joined: Nov 2002
Posts: 896
Likes: 3
From: Washington MO
HELP! Engine turns over --won't start?
O.K. Here's my problem with my 94 LT1 . Get in the car to go to work and as soon as I turn the key, I hear a loud "pop" or "bang" and the car won't start. Jump in the beater car, off to work I go.
After work I try again and heres what I get;
1. Engine turns over but won't start
2. If I hold the gasp pedal down while trying to start the car, it will start but run really poor.
3. If I continue to feather the gas it will stay running but I get alot of white smoke out the exhaust. I also get a lot of moisture out the exhaust. This seems to be mainly (90%) out the left side.
4. As soon as I let off the gas, the car will sputter then die and we start the whole process all over again.
The car ran fine the nite before. And I'm not sure what the "pop"/"bang" was this morning. It sounds like the timing is way off. Is it possible for an opti to go out "just like that". The current GM opti only has about 35K miles on it. And would a bad opti cause this condition? The white smoke kind of reminds me of those times when you run Sea Foam thru the engine, same type of smoke show. Smells bad to.
Any help greatly appreciated,
Zane
After work I try again and heres what I get;
1. Engine turns over but won't start
2. If I hold the gasp pedal down while trying to start the car, it will start but run really poor.
3. If I continue to feather the gas it will stay running but I get alot of white smoke out the exhaust. I also get a lot of moisture out the exhaust. This seems to be mainly (90%) out the left side.
4. As soon as I let off the gas, the car will sputter then die and we start the whole process all over again.
The car ran fine the nite before. And I'm not sure what the "pop"/"bang" was this morning. It sounds like the timing is way off. Is it possible for an opti to go out "just like that". The current GM opti only has about 35K miles on it. And would a bad opti cause this condition? The white smoke kind of reminds me of those times when you run Sea Foam thru the engine, same type of smoke show. Smells bad to.
Any help greatly appreciated,
Zane
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
My vote is for a head gasket leak putting coolant into one or more cylinders. It is common for the leak to occur on cylinder 6 and 8 first. Pull the plugs on the left side and see if the insulators have a greenish cast, or whatever the color of your coolant is.
Thread Starter
Burning Brakes
Joined: Nov 2002
Posts: 896
Likes: 3
From: Washington MO
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Sure could. Over the 14 hours coolant leaks into a cylinder and you crank it and during compression the cylinder with coolant stops the starter with a bang. Pull some plugs and find out.
Thread Starter
Burning Brakes
Joined: Nov 2002
Posts: 896
Likes: 3
From: Washington MO
What other damage can I except form a Hydo-lock condition? Dropped valve? Bent Rod? ???
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Id be guessing at a failed head gasket too. If it was running fine when you put it away, that doesnt mean a thing. It had 14 hrs for the pressure in the cooling system to push the coolant into the cylinder if indeed this is the issue.
If you dropped a valve id think youd have alot of noise while it turns over.
Do you have any DTCs to go with?
If you suspect it may have been coolant in 1 or more cylinders, pull all the plugs, unplug the coil and unplug the injectors, it should turn over very smooth and easy then (it should be a very consistant electric motor sound due to no compression with the plugs out). If it sounds good and smooth, put all the plugs back in, reconnect the coil and injectors, remove the radiator cap from your coolant surge tank, and see if it will start. By turning it over with the plugs out, any water in the cylinders will be pushed out through the plug holes, and with no pressure on the cooling system, very little if any can get back in. If it does start, look in the surge tank for bubbles, and if you have access to a coolant CO tester then do a CO test on the coolant while its running.
If you dropped a valve id think youd have alot of noise while it turns over.
Do you have any DTCs to go with?
If you suspect it may have been coolant in 1 or more cylinders, pull all the plugs, unplug the coil and unplug the injectors, it should turn over very smooth and easy then (it should be a very consistant electric motor sound due to no compression with the plugs out). If it sounds good and smooth, put all the plugs back in, reconnect the coil and injectors, remove the radiator cap from your coolant surge tank, and see if it will start. By turning it over with the plugs out, any water in the cylinders will be pushed out through the plug holes, and with no pressure on the cooling system, very little if any can get back in. If it does start, look in the surge tank for bubbles, and if you have access to a coolant CO tester then do a CO test on the coolant while its running.
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Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
The starter motor isn't powerfull enough to break anything in hydrolock, so I doubt you have any engine parts damaged. If you do have a leaking head gasket, then you can empty the cylinder/s of coolant when you take the heads off. Buy Fel-Pro teflon coated head gaskets, they last a long time. Conventional gaskets don't!
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
The starter motor isn't powerfull enough to break anything in hydrolock, so I doubt you have any engine parts damaged. If you do have a leaking head gasket, then you can empty the cylinder/s of coolant when you take the heads off. Buy Fel-Pro teflon coated head gaskets, they last a long time. Conventional gaskets don't!
Thread Starter
Burning Brakes
Joined: Nov 2002
Posts: 896
Likes: 3
From: Washington MO
Cylinders number 1-3-5 were at 145 lbs
Cylinder number 7 was 135 lbs
Cylinder number 5 would get to 145 lbs but wouldn't hold it. Slow leak down.
The plugs in cylinders 3 & 5 were wet and had a slight coolant smell to them.
So I'm going to start taking everything apart after work Monday and replace both head gaskets.
Any tips on what to do or not do whle I'm in there?
I'm thinking headers and a set of roller rockers!
Later Zane
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Wait til youre in there and see what its like inside first before you plan mods, and if you go with 1.6:1 RRs youll be needing new springs of a better standard. Let us know how ya go
Thread Starter
Burning Brakes
Joined: Nov 2002
Posts: 896
Likes: 3
From: Washington MO
Well. the heads are off, along with just about everything else under the hood! What a job! Number 3and 5 cylinders were full of coolant. The head gaskets on both sides were pretty much shot. Both were badly deteriorated, and by the looks of them, had been leaking slightly for some time. Their at the machine shop now being checked and I should have them back next week. In the mean time, I'll clean the engine compartment up real nice. I'll go ahead and change all the hoses, belt etc. when I reassemble everything. It'll be like driving a brand new car around the Texas Motor Speedway track next month.
I'm still looking into a set of headers and 1.6 roller rockers. Depends on if I have to have any major head rework done.
Later Zane
I'm still looking into a set of headers and 1.6 roller rockers. Depends on if I have to have any major head rework done.
Later Zane
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Well. the heads are off, along with just about everything else under the hood! What a job! Number 3and 5 cylinders were full of coolant. The head gaskets on both sides were pretty much shot. Both were badly deteriorated, and by the looks of them, had been leaking slightly for some time. Their at the machine shop now being checked and I should have them back next week. In the mean time, I'll clean the engine compartment up real nice. I'll go ahead and change all the hoses, belt etc. when I reassemble everything. It'll be like driving a brand new car around the Texas Motor Speedway track next month.
I'm still looking into a set of headers and 1.6 roller rockers. Depends on if I have to have any major head rework done.
Later Zane
I'm still looking into a set of headers and 1.6 roller rockers. Depends on if I have to have any major head rework done.
Later Zane
If you havent done so, get the oil drained out straight away, if it has any water in it this will damage the bearings.