Help... my 78 TA won't start!


Old 11-09-03, 04:21 AM
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Red face Help... my 78 TA won't start!

I own a 1978 Pontiac Trans Am which is approx. 99% original. It has the original 400 cid (6.6 ltr) motor and the 3-speed automatic. No modifications, other than adding a K&N filter, have been done to the engine. Here's my problem.
Just recently, the car has given up on me. Iím no mechanic, and I really donít have the money to bring it to a professional Ė so I was hoping someone might have some ideas, advice or thoughts. I had noticed a fairly large leak in my radiator recently, and had to run the car extremely hot on a couple of occasions. On one such occasion I pulled over on the interstate to let the motor cool and add water because the temp gauge had pegged all the way out. After it cooled down and the radiator was full, I couldn't get the car to start again. After towing it home, I found that when I tried to start the car it would crank as normal for a few seconds then act as if the battery had died. I checked the battery and it was fine. I also checked the starter and had to replace it. Now I am getting the car the crank, it's getting fuel and air, and most of the plugs are firing (unfortunately, a couple of the plugs looked like they might have water in them...). The water seems to tell me that I may have blown a head gasket, but I was wondering if you had run across this type of problem before, and if you had any thoughts or suggestions with correcting it. Some people tell me it could be the timing chain, others say it's the head gasket, and like I said, I'm not much of a mechanic, nor do I have the money to bring the car to a professional mechanic. Any thoughts? Any help will be greatly appreciated.
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Old 11-09-03, 08:19 AM
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no start

Unfortunatly,if you have water in a couple of cylinders & it is not
firing on cylinders to start with you will probably not be able to
get it start until major repairs are made(i.e. head gasket replaced)
If when it is cranking over it sounds like it is trying to back-fire
through the carb it could be a timing chain.
Old 11-09-03, 09:16 AM
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You may have cracked heads or block. Also needs torn down and get the heads checked.
Old 11-09-03, 10:08 AM
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You may have cracked heads or block. Also needs torn down and get the heads checked.
Old 11-09-03, 01:29 PM
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(Gasps for air as he comes up from passing out).

Yikes. NEVER run a car hot like that (no matter what it is) as you will lunch an engine faster than you can imagine. This is an old time cast iron block/head setup and is very forgiving of such abuse, but it has limits.

Pontiac engines (I own three of these same cars as you do, including two 400 equipped Trans Ams of this vintage) do not like to be run hot. It's imperative to keep the cooling system in order on these.

Word of advice: Dump the K&N filter and put the stock one back. K&N is a collosal waste of money and lets more dirt into the engine. Now to the actual problem:

These cars require a lot of upkeep but will reward you with thumbs up & increased value with years to come. I just got my 1980 Turbo Trans Am inspected and the guys in the shop were all gawking over it and it was no surprise that it passed the emission test with flying colors as it has for the past 23 years. LOL.

1) Fix the radiator. Have a radiator shop repair the radiator. If it's really shot, order a new Modine one (about 200 bones). It's a snap to put in.

2) Throw out all the belts and hoses----way overdue. Replace it with new ones.

3) Check the water pump for leakage too, common to go bad on an old Indian like this. While you're in there, order a new divider plate from GM (part #9796349) and two new cooling sleeves (part #9796347) as these will contribute to overheating.

4) Get things squared away. The car should crank and crank. If it wants to die when you crank, make sure your connections are good and your battery fully charged.

I do agree with the others that a blown gasket is a possibility especially if you drove it overheated for a while.

These are great looking, performing cars and are a breeze to service. Pick up a GM shop manual set for it on Ebay. You'll need the 1978 green shop manual and a 1978 Fisher body manual. All worth the money.

If you're going to keep the car yourself, invest in some basic tools and some books to guide you. These cars are simple simon to work on.

Kudos for it being a Pontiac 400 and not an Olds 403. The 400 run better, lasts longer and is worth more .
Old 11-10-03, 11:43 AM
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Your car is wasted--send it to me--I will pay you a fair price. For I unlike Joe only own one of these and need another one! LOL!
Old 11-10-03, 01:27 PM
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