Car hard to start when engine is cold.
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I have a 98 trans am. This problem is driving me nuts and I cannot pinpoint the cause. When the car hasn't been driven overnight or for a few days it won't start on the first few cranks. When it finally does start, the car runs great and has no problems. If I shut the car it will start right up again.
Before anyone says fuel pump, I have checked the fuel pressure. It is 60 PSI when the key is first turned on and remains at 50 when the pump turns off. It will keep pressure for hours after turning the key off. Also the fuel filter has been replaced.
The coolant temperature reads correctly with autotap and there are no trouble codes. The other day it was 70 degrees outside and the car stated up on the first try. When the temp gets down around 50 degrees, the problem seems to get worse "may take several minutes of cranking". I am out of things to try, does anyone have any suggestions for what to check. The worst part of diagnosing the problem is that the car eventually starts.
Before anyone says fuel pump, I have checked the fuel pressure. It is 60 PSI when the key is first turned on and remains at 50 when the pump turns off. It will keep pressure for hours after turning the key off. Also the fuel filter has been replaced.
The coolant temperature reads correctly with autotap and there are no trouble codes. The other day it was 70 degrees outside and the car stated up on the first try. When the temp gets down around 50 degrees, the problem seems to get worse "may take several minutes of cranking". I am out of things to try, does anyone have any suggestions for what to check. The worst part of diagnosing the problem is that the car eventually starts.
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I had this problem with one of my other cars and it turned out to be the pump. It started doing it again a few thousand miles later and I thought, theres no way it can be the pump again. I changed the plugs and used Rapidfires. Problem was cured. It started fine when warm, but when it was 30 or so out, it took too many cranks.
Brad
Brad
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My friend's SSlowmaro <img src="images/icons/wink.gif" border="0"> had a problem starting and idling when it was cold outside for a while. It ended up being a loose vaccum line. Only takes a sec to check. Food for thought. <img src="images/icons/smile.gif" border="0">
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Well today it wouldn't start again. I am getting NO spark. I tested spark on one of the plugs and it wasn't showing any. I continued cranking for about another 30 seconds and as soon as I saw a spark the car fired up. The car has a brand new battery. It has never ran rough or stalled. Does anyone have a wire diagram of the ignition system?? I would think if it is the crank sensor, the car would show more problems than starting.