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1980 Trans AM Just Dies When Warmed Up?

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Hi.

Hoping someone out there can help me.

I got my carb redid, transmission, and a slew of other things.

It was running OK; however, the choke relay under the dash was buzzing.

I replaced it with a new relay, and the buzzing stopped.

The choke works fine now. my problem now is when the car is warm, the car just bogs(dies).

I adjusted the base idle screw to 900 rpm.

When in drive, the RPM's are 750.

It starts really nice but dies on me when at normal running temperature.

Also, when the car is about to die, you can see gas squirting out of the primary ports.

Any idea out there.

Thanks in advance
Mike
 

Pontiac Trans Am

Smokey
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Before it shuts off, does it do anything strange like back fire or anything like that?

Thank you,
PTA Staff
 
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Hi Smokey.

It starts really well from cold.

The choke plate slowly opens up and then, when warm, stays open.

After running for a while, it then starts to run a bit rough then dies.

It will start up right away and run nicely, then just dies.

I did play around with the idle screw on the driver's side before this all started.

The green choke relay was buzzing.

I have ordered and replaced the relay.

The choke plate opens up really nice now.

I was thinking of turning in the screw all the way in, then start the car and turn out the screw until it reaches 900 RPMs.

In the park and 750 RPM's in the drive?

Do you think that may help?
 
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Pontiac Trans Am

Smokey
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It sounds like it could be a choke issue since it dies when it comes off the high idle.

Thank you,
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Hi Smokey

To answer your earlier question, it does do a slight backfire, sometimes not really a lot.

If you think it is a choke issue, what could I do to look into this?
 
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Pontiac Trans Am

Smokey
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Hi Smokey

To answer your earlier question, it does do a slight backfire, sometimes not really a lot.

If you think it is a choke issue, what could I do to look into this?
Yes, cause it runs good until the choke comes off, which makes us think it could be the choke.

Thank you,
PTA Staff
 
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Hi Guys,

I pulled the fuel line off and turned on the engine, and had the fuel dump into a jar.

It looks like there is debris in the gas tank.

This may be plugging the carb and causing the carb to stall.

Since the tank is 40 years old, I am thinking of replacing the tank.

The guy who rebuilt the carb thinks there may be debris plugging up the carb from the gas tank, making the carb die off.
 
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Pontiac Trans Am

Smokey
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Hi Guys,

I pulled the fuel line off and turned on the engine, and had the fuel dump into a jar.

It looks like there is debris in the gas tank.

This may be plugging the carb and causing the carb to stall.

Since the tank is 40 years old, I am thinking of replacing the tank.

The guy who rebuilt the carb thinks there may be debris plugging up the carb from the gas tank, making the carb die off.
Oh yeah, you are fighting a never winning battle there.

Change the tank and check the whole fuel system.

Thank you,
PTA Staff
 
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Hi Smokey

I have gone on a few sites and found firebird central with the following:

1979 - 1981 Pontiac Firebird Fuel Gas Tank, Premium Quality

Correct Fuel Gas Tank for 79 - 81 Pontiac Firebird models.

Premium quality.

Made with corrosion-resistant O.E.M. approved Ni Terne steel.

All units are water-based leak tested after full product assembly.

Lock ring and gasket included. Order yours today! Replaces GM Part # 475497 perfectly.

This is the North American Made premium quality fuel tank your Firebird deserves!

The sending unit is as follows:

1976 - 1981 Firebird Fuel Tank Sending Unit with 3/8 Gas and 1/4 Vent Return Line

New factory correct design fuel tank sending unit for your bird. Exact fit for all 76 - 81 Firebird and Trans Am models.

Features a 3/8" main gas line with a 1/4" vent return line.

Includes mounting locking ring and rubber gasket.

The fuel line exits out on the right-hand passenger side.

PART NUMBER: FUE-2000

I assume that the tank and sending unit are OK.

Also, what is the best method to paint it black?

any help appreciated

Thanks, Mike
 
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Bob

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Any paint thinner or brake cleaner will clean the outside of the tank to get rid of the oily residue.

I would scuff it with a green Scotch Brite pad, wipe it down again and then use self etching primer and then paint.

Good luck; let us know how you make out.
 
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