95 Trans Am Startup problem
Thread Starter
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Joined: Mar 2010
Posts: 7
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From: Ohio
95 Trans Am Startup problem OKay guys, I did a search on the forums and didn't find anything really that fit this problem. So if anyone knows of a thread I missed and can direct me there, then I would greatly appreciate it.
My brother bought a 1995 trans am. When it is cold, it starts up fine. When it is warm, the car acts almost bogged down and takes a few cranks to start. If I am standing behind it, when it does this, it blows out a puff of black exhaust smoke when it starts and then it is fine. Doesn't blow out black smoke at any other time including WOT.
The low coolant light is on, and the coolant isn't low. The person he bought it from said it is a bad sensor. From reading the forums I got the impression that this sensor can be the cause of this slow start up issue, but I just have never heard of that before.
Also, the opti-spark has been replaced and the starter doesn't seem like its bad since it only does it when it is warm.
Any help, advice or direction to point us in would be great.
Thanks!
My brother bought a 1995 trans am. When it is cold, it starts up fine. When it is warm, the car acts almost bogged down and takes a few cranks to start. If I am standing behind it, when it does this, it blows out a puff of black exhaust smoke when it starts and then it is fine. Doesn't blow out black smoke at any other time including WOT.
The low coolant light is on, and the coolant isn't low. The person he bought it from said it is a bad sensor. From reading the forums I got the impression that this sensor can be the cause of this slow start up issue, but I just have never heard of that before.
Also, the opti-spark has been replaced and the starter doesn't seem like its bad since it only does it when it is warm.
Any help, advice or direction to point us in would be great.
Thanks!
I suspect the temperature sender. It tells the computer the engine temperature and when they fail they fail 'safe' and in this case tells the computer the car is cold.
When the engine is warm the computer is still injecting extra fuel for an ice cold engine the engine has trouble with the excess fuel and when it finally starts puts out black smoke. I suspect the gas mileage has also taken a dump.
The easiest way to check is to pull the connector off the temp sensor (careful breaks easily) in the water pump and check the ohms between the two connections on the sensor. Go to a parts store read the resistance at parts store (both ~70 degrees) if the sensor is bad they will not be close.
Look carefully at the connector on the sender then when you go to parts store you will recognize if it is the correct one.
Good luck the sender I think is 5/8" if I remember.
And welcome.
EDIT I think it is 13/16 remember not being able to use plug socket
When the engine is warm the computer is still injecting extra fuel for an ice cold engine the engine has trouble with the excess fuel and when it finally starts puts out black smoke. I suspect the gas mileage has also taken a dump.
The easiest way to check is to pull the connector off the temp sensor (careful breaks easily) in the water pump and check the ohms between the two connections on the sensor. Go to a parts store read the resistance at parts store (both ~70 degrees) if the sensor is bad they will not be close.
Look carefully at the connector on the sender then when you go to parts store you will recognize if it is the correct one.
Good luck the sender I think is 5/8" if I remember.
And welcome.
EDIT I think it is 13/16 remember not being able to use plug socket
Last edited by boosted LT1; Apr 26, 2010 at 10:36 AM.
BEFORE you pull the older sensor make sure you have the correct one to replace it.
Check the elctrical connector before and when you remove the old one immediately put the new one in. Coolant can easilly get on and in the opti and cause serious problems.
I usually put rags to keep coolant away from the opti when I do anything near the opti.
Best to do it on a cold engine so he can put his finger over the hole and guide the new one in avoiding coolant running off.
Good luck 5 minute job once you have socket or wrench and new sensor ready.
Good luck
Check the elctrical connector before and when you remove the old one immediately put the new one in. Coolant can easilly get on and in the opti and cause serious problems.
I usually put rags to keep coolant away from the opti when I do anything near the opti.
Best to do it on a cold engine so he can put his finger over the hole and guide the new one in avoiding coolant running off.
Good luck 5 minute job once you have socket or wrench and new sensor ready.
Good luck
Thread Starter
Registered User
Joined: Mar 2010
Posts: 7
Likes: 0
From: Ohio
I suspect the temperature sender. It tells the computer the engine temperature and when they fail they fail 'safe' and in this case tells the computer the car is cold.
When the engine is warm the computer is still injecting extra fuel for an ice cold engine the engine has trouble with the excess fuel and when it finally starts puts out black smoke. I suspect the gas mileage has also taken a dump.
The easiest way to check is to pull the connector off the temp sensor (careful breaks easily) in the water pump and check the ohms between the two connections on the sensor. Go to a parts store read the resistance at parts store (both ~70 degrees) if the sensor is bad they will not be close.
Look carefully at the connector on the sender then when you go to parts store you will recognize if it is the correct one.
Good luck the sender I think is 5/8" if I remember.
And welcome.
EDIT I think it is 13/16 remember not being able to use plug socket
When the engine is warm the computer is still injecting extra fuel for an ice cold engine the engine has trouble with the excess fuel and when it finally starts puts out black smoke. I suspect the gas mileage has also taken a dump.
The easiest way to check is to pull the connector off the temp sensor (careful breaks easily) in the water pump and check the ohms between the two connections on the sensor. Go to a parts store read the resistance at parts store (both ~70 degrees) if the sensor is bad they will not be close.
Look carefully at the connector on the sender then when you go to parts store you will recognize if it is the correct one.
Good luck the sender I think is 5/8" if I remember.
And welcome.
EDIT I think it is 13/16 remember not being able to use plug socket
Thank you! Great explanation on why the sensor would cause that BTW... now I get it! I will pass this along to him and probably help him do it this weekend. Thanks again!
I had a similar problem with mine once, although it did not do it every time the car was warm, just occassionally. It turned out to be a bad fuel pressure regulator. If the idea above does not pan out, try the f.p.r. It is attached to the back of the intake (kind of hard to reach back there) closer to the drivers side. It is connected to the end of the fuel rail. There is a small vacuum line that runs from the f.p.r. to the passenger side of the intake. Pull that vacuum line and see if gas drips out of it or if you can smell gas vapors in it. If so, it could be letting excess fuel leak back into your intake causing the hard starts.
Thread Starter
Registered User
Joined: Mar 2010
Posts: 7
Likes: 0
From: Ohio
I had a similar problem with mine once, although it did not do it every time the car was warm, just occassionally. It turned out to be a bad fuel pressure regulator. If the idea above does not pan out, try the f.p.r. It is attached to the back of the intake (kind of hard to reach back there) closer to the drivers side. It is connected to the end of the fuel rail. There is a small vacuum line that runs from the f.p.r. to the passenger side of the intake. Pull that vacuum line and see if gas drips out of it or if you can smell gas vapors in it. If so, it could be letting excess fuel leak back into your intake causing the hard starts.
Haha.. everything in that engine bay is hard to reach. That's a good idea though. Seems like an easy thing to check too. Thank you!
