1991 Trans Am GTA 5.7l TPI
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Car: 1991 Firebird Trans Am GTA
Engine: 5.7L TPI
Transmission: 700R4
1991 Trans Am GTA 5.7l TPI
I have an overheating and oil pressure issue. There is about 130000 miles on my motor. It all starts up perfectly and runs smooth warming up and once its warmed up it still runs smooth. Oil pressure is around 45 or so when it is warming up. Once it is warmed up the oil pressure drops down alot. The lowest I have seen it drop is around 5 or 10 PSI. I have seen some things that says it could be the cam bearings causing the oil pressure to drop. Is this correct? I also have an issue with the car over heating very bad. The other day I was driving and saw some smoke come out under the hood, pulled over and the over flow tank was about 3/4 full and boiling....Not good at all... Could these issues be related or will they more than likely be unrelated issues? Any help and ideas for these issues is appreaciated!
#2
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They're unrelated. The oil pressure could be a non issue. The gauges aren't necessarily accurate. Sending unit or gauge itself maybe wrong. Use a mechanical oil pressure tester to find out for sure.
Overheating you treat like any other overheating vehicle. Is the thermostat opening? Fans kicking on? Water pump ok? ....or is its bearings good? Coolant leaks?
Overheating you treat like any other overheating vehicle. Is the thermostat opening? Fans kicking on? Water pump ok? ....or is its bearings good? Coolant leaks?
Last edited by aliceempire; 05-09-2016 at 03:33 PM.
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Car: 1991 Firebird Trans Am GTA
Engine: 5.7L TPI
Transmission: 700R4
Re: 1991 Trans Am GTA 5.7l TPI
They're unrelated. The oil pressure could be a non issue. The gauges aren't necessarily accurate. Sending unit or gauge itself maybe wrong. Use a mechanical oil pressure tester to find out for sure.
Overheating you treat like any other overheating vehilce. Is the thermostat opening? Fans kicking on? Water pump ok? ....or is its bearings good? Coolant leaks?
Overheating you treat like any other overheating vehilce. Is the thermostat opening? Fans kicking on? Water pump ok? ....or is its bearings good? Coolant leaks?
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Car: 1991 Firebird Trans Am GTA
Engine: 5.7L TPI
Transmission: 700R4
Re: 1991 Trans Am GTA 5.7l TPI
Where is the temp sensor for the gauge located? If I change that and I'm still not getting anything would it be easier to run it to an aftermarket gauge or would that require extra wiring and such? I think the overheating issue is going to just be my thermostat, like I said earlier, I have replaced the water pump, and I have also replaced the radiator and see no signs of a coolant leak.
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Car: 1991 Firebird Trans Am GTA
Engine: 5.7L TPI
Transmission: 700R4
Re: 1991 Trans Am GTA 5.7l TPI
They're unrelated. The oil pressure could be a non issue. The gauges aren't necessarily accurate. Sending unit or gauge itself maybe wrong. Use a mechanical oil pressure tester to find out for sure.
Overheating you treat like any other overheating vehicle. Is the thermostat opening? Fans kicking on? Water pump ok? ....or is its bearings good? Coolant leaks?
Overheating you treat like any other overheating vehicle. Is the thermostat opening? Fans kicking on? Water pump ok? ....or is its bearings good? Coolant leaks?
in regaurds to the oil pressure issue, what is the procedure for testing it with an external gauge? Is it possible the drop in oil pressure could be due to the cam bearings being worn out?
#7
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Re: 1991 Trans Am GTA 5.7l TPI
Easiest option to test oil pressure is to pull the sending unit out that is above the oil filter and connect a normal craftsman/snapon/mac/parts store rental gauge to it. I don't think worn cam bearings would make any change as it gets hot. I would believe it to be a constant problem if bearings are a problem. But trust me...these gauges are wrong frequently.
What makes you think the cam bearings are bad? Even at 130,000 mi it wouldn't be high on my list of suspects.
What makes you think the cam bearings are bad? Even at 130,000 mi it wouldn't be high on my list of suspects.
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Car: 1991 Firebird Trans Am GTA
Engine: 5.7L TPI
Transmission: 700R4
Re: 1991 Trans Am GTA 5.7l TPI
Easiest option to test oil pressure is to pull the sending unit out that is above the oil filter and connect a normal craftsman/snapon/mac/parts store rental gauge to it. I don't think worn cam bearings would make any change as it gets hot. I would believe it to be a constant problem if bearings are a problem. But trust me...these gauges are wrong frequently.
What makes you think the cam bearings are bad? Even at 130,000 mi it wouldn't be high on my list of suspects.
What makes you think the cam bearings are bad? Even at 130,000 mi it wouldn't be high on my list of suspects.
#9
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Re: 1991 Trans Am GTA 5.7l TPI
Depending on the gauge, you may be able set it up to see it while driving but I doubt it. Personally, I'd hook it up, keep it away from the exhaust, and let it run. If you have to drive it, find a place for the gauge to hang happily. Park and check it again when the engine should be hot.
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Car: 1991 Firebird Trans Am GTA
Engine: 5.7L TPI
Transmission: 700R4
Re: 1991 Trans Am GTA 5.7l TPI
Sounds good. After talking with you, it sounds like I shouldn't have any MAJOR problems. Just a few things to sort through and check. Thanks for your help. I am going to PM you if I have any more questions or need some more help. Thanks!!
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