low compression?
#1
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low compression?
We need a totorial on how to find thingsusing the search (Its hard).
My car............ah, is a piece, I mean wont start. It has been having problems starting lately and over the last month has gotten progressivily more difficult to start until now it will not start on its own. From what I understand this is a sign of low compression, not good?
The car will start very easily If pull started, only takes 15-20 feet to start, and runs fine afterwards (started it last night this way drove around to warm it up, shut it down and restarted it just fine, usually fights more after warming up.) this makes me think that it is not a compression problem, does thisgive anyone any insight as to what the problem could be?
after running it last noght I shut it down, this morning it would not start again. Im still lost.
Any input will be appreciated
Dustin
My car............ah, is a piece, I mean wont start. It has been having problems starting lately and over the last month has gotten progressivily more difficult to start until now it will not start on its own. From what I understand this is a sign of low compression, not good?
The car will start very easily If pull started, only takes 15-20 feet to start, and runs fine afterwards (started it last night this way drove around to warm it up, shut it down and restarted it just fine, usually fights more after warming up.) this makes me think that it is not a compression problem, does thisgive anyone any insight as to what the problem could be?
after running it last noght I shut it down, this morning it would not start again. Im still lost.
Any input will be appreciated
Dustin
#2
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Carb or FI? Are you sure it's not flooding? Starter turning it over fast enough? Have you tried using a little ether based starting fluid?
Many different issues can cause poor starting behaviour, including old spark plugs/wires/dizzy cap and rotor.
Many different issues can cause poor starting behaviour, including old spark plugs/wires/dizzy cap and rotor.
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its a '79 with a S2 12a and turbo preped 45dcoe (no choke)
it does flood eventually, but the last couple weeks its taken a god fourty five seconds to a minute of crank and pump, stop, pump, crank, ckrank and pump to start it and it had been starting every time, until the other day.
has anyone had experience with this compression loss disease ive heard of?
my problem is lack of funds, I have an engine im building, just need springs, but I have no job, so I need a car so I can get a job.
I guess what im wanting to know is anyone who has had this kind of problem what has worked, ive been told to do the decarbonizing trick but it does not seem to ave a compression problem?......
it does flood eventually, but the last couple weeks its taken a god fourty five seconds to a minute of crank and pump, stop, pump, crank, ckrank and pump to start it and it had been starting every time, until the other day.
has anyone had experience with this compression loss disease ive heard of?
my problem is lack of funds, I have an engine im building, just need springs, but I have no job, so I need a car so I can get a job.
I guess what im wanting to know is anyone who has had this kind of problem what has worked, ive been told to do the decarbonizing trick but it does not seem to ave a compression problem?......
#7
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I would start by verifying that you have decent compression.
If you want a relatively accurate compression test you can use a conventional compression tester. Heres the process.
Disable the fuel system, pull the fusible link, plug the fuel lines whatever. You don't want fuel into the chambers when you are turning the engine over.
Pull all of the plug wires.
Pull the trailing (top) plugs from both rotors.
Screw in the compression tester in the top hole of the front rotor. Hold the release "pin" in on the tester, this will allow the pressure to immediately release on each compression "stroke".
Have someone hold the gas pedal to the floor and turn the car over while you watch the gauge. You should see the needle on the gauge start "bumping" up and down. After watching for a few cycles, you can see the three compression cycles. They should all be fairly consistent and not too low.
Repeat the process with the rear rotor.
Also, the car needs a fully charged battery and good starter. It needs to rotate around 250 rpm to get a decent reading.
If you want a relatively accurate compression test you can use a conventional compression tester. Heres the process.
Disable the fuel system, pull the fusible link, plug the fuel lines whatever. You don't want fuel into the chambers when you are turning the engine over.
Pull all of the plug wires.
Pull the trailing (top) plugs from both rotors.
Screw in the compression tester in the top hole of the front rotor. Hold the release "pin" in on the tester, this will allow the pressure to immediately release on each compression "stroke".
Have someone hold the gas pedal to the floor and turn the car over while you watch the gauge. You should see the needle on the gauge start "bumping" up and down. After watching for a few cycles, you can see the three compression cycles. They should all be fairly consistent and not too low.
Repeat the process with the rear rotor.
Also, the car needs a fully charged battery and good starter. It needs to rotate around 250 rpm to get a decent reading.
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