Starts, idles low, then dies after 2 minites. ?
08-24-2006, 01:21 PM
#2
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Originally Posted by SayNoToPistons' post='834064' date='Aug 24 2006, 08:15 AM
Why would a n/a FC start and idle low for 2 minites then die? dont know the compression yet but the seller saids it works if you keep your foot on the gas in neutral while driving. Whats going on?
08-24-2006, 10:40 PM
#4
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Honestly, giving someone the advice "do a compression check" isnt very helpful. First of all, the odds of someone being in his area with a working rotary compression checker and knowing how to properly use it is remote. Secondly, its a rotary, not a piston engine. If it has enough compression to start on its own, its fine.
If the car starts and runs fine, but you have you keep your foot in it to keep it from dying, you have some leak in the system that is allowing unmetered air entering the motor. The reason why it doesnt die for the first 2 minutes is because the thermo wax is kicking the idle speed up high enough to where it wont stall out. But once it warms up, the idle drops too low.
Check for obvious sources of air leaks, vacuum hoses, etc. Could also be a leaky ACV.
If the car starts and runs fine, but you have you keep your foot in it to keep it from dying, you have some leak in the system that is allowing unmetered air entering the motor. The reason why it doesnt die for the first 2 minutes is because the thermo wax is kicking the idle speed up high enough to where it wont stall out. But once it warms up, the idle drops too low.
Check for obvious sources of air leaks, vacuum hoses, etc. Could also be a leaky ACV.
08-25-2006, 01:24 AM
#5
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Originally Posted by cymfc3s' post='834227' date='Aug 24 2006, 11:40 PM
Honestly, giving someone the advice "do a compression check" isnt very helpful. First of all, the odds of someone being in his area with a working rotary compression checker and knowing how to properly use it is remote. Secondly, its a rotary, not a piston engine. If it has enough compression to start on its own, its fine.
If the car starts and runs fine, but you have you keep your foot in it to keep it from dying, you have some leak in the system that is allowing unmetered air entering the motor. The reason why it doesnt die for the first 2 minutes is because the thermo wax is kicking the idle speed up high enough to where it wont stall out. But once it warms up, the idle drops too low.
Check for obvious sources of air leaks, vacuum hoses, etc. Could also be a leaky ACV.
Down boy.
08-25-2006, 09:58 AM
#6
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Originally Posted by cymfc3s' post='834227' date='Aug 24 2006, 11:40 PM
Honestly, giving someone the advice "do a compression check" isnt very helpful. First of all, the odds of someone being in his area with a working rotary compression checker and knowing how to properly use it is remote. Secondly, its a rotary, not a piston engine. If it has enough compression to start on its own, its fine.
If the car starts and runs fine, but you have you keep your foot in it to keep it from dying, you have some leak in the system that is allowing unmetered air entering the motor. The reason why it doesnt die for the first 2 minutes is because the thermo wax is kicking the idle speed up high enough to where it wont stall out. But once it warms up, the idle drops too low.
Check for obvious sources of air leaks, vacuum hoses, etc. Could also be a leaky ACV.
08-25-2006, 03:17 PM
#8
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Originally Posted by Peepsalot' post='834316' date='Aug 25 2006, 10:45 AM
Is there a reason a normall compression tester does not work well with wankels?
Often times the numbers you get are inaccurate or ambigious. For a piston engine, when you have air escaping past the valve guides or rings, a compression check can be a very accurate representation of the engine's health. For a rotary, especially an NA, if the car starts and doesnt sound like a helicopter, its fine. In fact, the higher mileage the engine, the more compression it will build because the apex seal grooves are worn and allow combustion to push the apex seal up.
So, Im not saying don't do a compression check, but that shouldnt be your first reaction. These cars are old. You just gotta stick your head in the engine bay and figure it out.
08-25-2006, 04:14 PM
#9
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Location: California
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bollocks! compresstion testers vary a lot anyways, and then the rotary's compression also varies a lot with rpms, and altitude. so a compression test on a rotary you're looking for even bounces but the actual number isnt that big a deal
08-27-2006, 06:56 PM
#10
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Join Date: Aug 2006
Posts: 12
same problem with my car..in the process of figuring it out
i think on mine the problem is a cracked hose from the turbo to the air flow meter...
but we havent fixed it yet so im not sure
but according to what everyone else is saying that might be the problem
makes sense
i think on mine the problem is a cracked hose from the turbo to the air flow meter...
but we havent fixed it yet so im not sure
but according to what everyone else is saying that might be the problem
makes sense