Car running like crap...
Le Mans Master
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
I see you are in Jersey. May be related to the colder weather. How is the condition of your choke/carb warm-up circuit? Am wondering if your choke is not setting or perhaps the thermal vacuum actuator on your air cleaner is not feeding warm air to the carb. I get around this with a good choke and richer jetting on the carb (thx to Lars). Warms up longer but is fine once warm.
Instructor
Joined: Mar 2005
Posts: 135
Likes: 0
From: Northern NJ
Stewart, I always try to look for the easy stuff first. If the condition came on quickly, then what could have gone wrong quickly?
Cracked Disrtributor cap? Bad Rotor? Bad Coil? Failing fuel pump?
If the condition progressed slowly, it may be a dirty fuel problem, but that is not something likely. If you had just filled up, I would check that. Check your plugs. Black plugs may mean the float in the q-jet has sunk. Are you flooding at idle? Let it run and pull a couple of plugs. Smell them, raw fuel smell will indicate carb is dumping fuel. Check your fuel lines. I didn't see your engine compartment at TFB, but if you have any sections of rubber fuel line, be sure nothing is kinked or swelled closed.
Cracked Disrtributor cap? Bad Rotor? Bad Coil? Failing fuel pump?
If the condition progressed slowly, it may be a dirty fuel problem, but that is not something likely. If you had just filled up, I would check that. Check your plugs. Black plugs may mean the float in the q-jet has sunk. Are you flooding at idle? Let it run and pull a couple of plugs. Smell them, raw fuel smell will indicate carb is dumping fuel. Check your fuel lines. I didn't see your engine compartment at TFB, but if you have any sections of rubber fuel line, be sure nothing is kinked or swelled closed.
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
Do you have another coil or distributor that you can install ?
It may be the coil (idles fine, upon heavy throttle, the car sputters badly and wont accelerate like it should), had the same symptoms on my wife's car, it was the coil...
... just get one at AZ and if it doesn't fix the problem bring it back...ooops...did I say that ???
It may be the coil (idles fine, upon heavy throttle, the car sputters badly and wont accelerate like it should), had the same symptoms on my wife's car, it was the coil...
... just get one at AZ and if it doesn't fix the problem bring it back...ooops...did I say that ???
Burning Brakes
Joined: Jul 2000
Posts: 963
Likes: 0
From: melbourne,Australia
Stewart,if you have checked the electrical sideand all is working as it should then you are down to fuel issues.....on the later tanks they have a rubber insert that can fail/block fuel pick up but the 74 shouldnt have one.....sounds like there may be some sort of partial blockage on fuel pickup...(cure,drain clean tank) or somehow the tank vent is bloking causing resistance to fuel pickup......is there a loud whoosh when you take the gas cap off?.....if there is it means the tank isn't venting and will need to be rectified.......presumably you have replaced the fuel filter?......hard to guess what else it could be.......john 
Racer
Joined: Feb 2004
Posts: 265
Likes: 1
From: Irwindale Ca
coil coil coil... haha, does it run fine when cold and when it heats up goes south?... My coil did that.. It would be fine cold full power. When it warmed up, it would pop and sputter.. i would have to crawl it home with minimal throttle. It would idle fine though. Changed the coil with a used one and full power. That one really stumped me. Im betting its the coil. Let us know... this is gettin interesting.
Race Director
Joined: Feb 1999
Posts: 16,978
Likes: 7
From: In Dreams There Is Truth Ohio
If it's the coil, take it to Auto Zone, they can check it for FREE..
I would still throw in new plugs...by now your plugs are prolly fouled with the way the motor has been running
I would still throw in new plugs...by now your plugs are prolly fouled with the way the motor has been running
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Thread Starter
Safety Car
Joined: Aug 2000
Posts: 3,943
Likes: 44
From: Florham Park NJ Port Credit Ontario
I checked the timing yesterday and the Dist hasnt moved as suggested.
I've also done the following:
New fuel filter
Checked for Vac Leaks. All Ports are plugged on carb.
I switched my vac advance from manifold back to ported. It used to run good that way.
Checked all plug wires, they are connected correctly and tight.
Popped cap off dist. All internals work smoothly.
Re-Timed car to Lars specs.
Pulled Valve coves off. Checked Valve lash, rockers and springs...all seemed OK.
One other thing that has me very concerned.
Now I hear a ticking sound coming out of the driver side exhaust. Cant hear the sound when you are in the car or near the engine compartment...only when standing behind the car.
I'm pretty bummed.
I dont get it. When revving the motor in the driveway, it acts fine. When driving and getting into the throttle, it balks/hesitates/stumbles badly.
Stewart
I've also done the following:
New fuel filter
Checked for Vac Leaks. All Ports are plugged on carb.
I switched my vac advance from manifold back to ported. It used to run good that way.
Checked all plug wires, they are connected correctly and tight.
Popped cap off dist. All internals work smoothly.
Re-Timed car to Lars specs.
Pulled Valve coves off. Checked Valve lash, rockers and springs...all seemed OK.
One other thing that has me very concerned.
Now I hear a ticking sound coming out of the driver side exhaust. Cant hear the sound when you are in the car or near the engine compartment...only when standing behind the car.
I'm pretty bummed.
I dont get it. When revving the motor in the driveway, it acts fine. When driving and getting into the throttle, it balks/hesitates/stumbles badly.
Stewart
Melting Slicks
Joined: Sep 2002
Posts: 2,783
Likes: 2
From: Engineers do it better.
Check you coil Stewart. Mine does the same thing: idles great and sputters under heavy load. My car is put away for winter, and I never checked the coil. I am interested in finding out as well....
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
hey stu...did you think about a bad fuel pump? that is only giving enough juice at idle and in the drive and when you are actually loading the engine and requiring more juice its taking time to recover.....these fuel pumps can linger near death for a long time and really screw with you.
Thread Starter
Safety Car
Joined: Aug 2000
Posts: 3,943
Likes: 44
From: Florham Park NJ Port Credit Ontario
Bob, I have been thinking about that.
Here's what I'll be doing.
New points, condenser, coil and plugs.
easy to do swaps before I climb under the car and tackle the fuel pump.
Here's what I'll be doing.
New points, condenser, coil and plugs.
easy to do swaps before I climb under the car and tackle the fuel pump.
Racer
Joined: Feb 2004
Posts: 265
Likes: 1
From: Irwindale Ca
wow , thought you had HEI distributor. I think the coil still might be the culprit. Although a bad fuel pump or clogged fuel filter could be also. If you change the dwell on the points the timing will be off. This is why i love HEI distributors soo much. I would upgrade to HEI unless you want stock of course. Plop them in and go...If all else fails, id start from scratch
Check compression, Check for fuel (accelerator pump), check plugs and wires for shorting, Check distributor dwell and timing....COIL.....This is getting interesting.
Check compression, Check for fuel (accelerator pump), check plugs and wires for shorting, Check distributor dwell and timing....COIL.....This is getting interesting.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Originally Posted by Stewart's74
Bob, I have been thinking about that.
Here's what I'll be doing.
New points, condenser, coil and plugs.
easy to do swaps before I climb under the car and tackle the fuel pump.
Here's what I'll be doing.
New points, condenser, coil and plugs.
easy to do swaps before I climb under the car and tackle the fuel pump.