Lord, thanks for not taking me! 7/30/08 Update.... Back in business!

[wally426ci]

So, once again, Im still on this great 6 month troubleshooting trail....  which has lead to me taking the car out maybe twice on a real trip this year.

My latest issue is still pretty much the same, Ive got 34* total, 18* initial, 15psi vac. and i unhooked the vacuum advance this time to eliminate that. I put a 180 thermo in, didnt make a huge difference on the factory gauge; I take the car out yesterday afternoon and it ran fine for maybe 10 mins of burning around the neighborhood, but i get to the next redlight and it will idle normal a minute, then it will slowly drop until you can tell its stumbling more and more, each redlight getting worse. until finally i pull in the drivewawy and it dies. 

So, is it possible that when i changed up jets that the oem fuel pump cant handle that fuel need? is there somewhere hidden that im not seeing a vacuum leak?  Its tough b/c i cant spend a whole day on it, i get an hour here and there and my patience is low. I just dont see how it could run fine last year (with the advance hooked to the wrong vacuum port) and this year, after i got the wiring situated at the ballast resistor, and changed to electric choke, its F'd! 

No the choke isnt stuck on, i could feel that it was totally open.             

[LAA66]

 Sorry I haven't followed your saga so maybe this was covered already. Sounds like it runs worse as it warms up. Possibly too rich, how is the float level also. The coil can fade as it gets hot too, what system are you running.

[BIGSHCLUNK]

I was thinkin' carb too. But I am not aware of your whole situation. Someone here should have an answer... 
Here's a little insite that may help, from the oddball fix department. My buddy's GTO would run fine then NOT. After a resetting timing and carb about a gajillion times... turns out the plate in the distributor was walking the more he ran it. Throwing timing out ruff idle ect. He replaced the dist, now it's all good! BTW this was a points dist upgraded to an hei.  Good Luck!

[Chryco Psycho]

possibly the carb is just getting so hot it is boiling the fuel , try a spacer or heat deflecting alum plate

[Changin Gears]

Longshot - are you pulling a vacumm in your fuel tank.  After you drive for a while and trouble starts, remove the gas cap to check.

[wally426ci]

Ive pulled a little vacuum in the tank but usually if the fuel level gets low. I already am running a spacer. Im getting a suggestion that the ECU could be getting hot from the Abodies site. Im gonna try another ECU and see. I cant see why everything would be getting so hot though, since it was fine last year. I really may have overheated the ECU when i soldered, so im starting there. The Distributor isnt that old either......

[LAA66]

 I was going to mention the ECU if that is the system you are running. I have read the standard orange box can vary timing even when working to their potential. Always good to have a spare anyway if that's not the problem.

[Super Blue 72]

Sorry you're having do much trouble... 

Just on the vacuum note, not that this is the problem, once other things are sorted out, when the car is having the stumbling problem, having someone in the car or you can do it under the hood, try to keep the idle up enough so it doesn't die and give a letting pull on the vacuum hoses, especially at the base of the carb as those tend to make turns and that's where leaks can occur.  As the under hood temps increase, the vacuum hoses may expand enough to show up as a problem, such as stumbling or other rpm changes.

This happened to me a little while ago.  Car wouldn't run under 2k rpm unless I controlled it with the pedal.  I guess 30+ year old vacuum hose doesn't work well.  Also check at the vacuum "t"s, some just barely held on to them.  The hoses I had just snapped off at the carb base. Also the condenser on the coil (small block) was touching the vac. hose to the dist. and kinking it.

[wally426ci]

Ive heard that the condenser is not needed........ is that true? and if not, which side does it hook to?

[Super Blue 72]

Ive heard that the condenser is not needed........ is that true? and if not, which side does it hook to?

I dunno.    Got me on that one...  I have it there so assume I need it?    Let me run out and take a loosey what terminal of the coil it's on.  I have a stock ignition system if that matters.

[Super Blue 72]

Ok, on the "+" terminal on the coil, same terminal as the red wire off the coil, grounded on the intake manifold I assume.  (Small block engine.)

[wally426ci]

Thanks  Yeah, i dont have an Orange box or anything.. I did just throw a cheap replacement ECU on there and it didnt seem to make a difference. Although, the old one was melted enough to see the 2 red tube looking thingy's. It was an NOS one I found a long time ago, been on the car 4 or 5 years.

[Super Blue 72]

Although, the old one was melted enough to see the 2 red tube looking thingy's.

   Melted?  What have you for hunches as to why it's melted?  (Sorry if you've explained this a  million times already...  ).  Go with the easy obvious stuff first.  Check/replace all the vacuum hoses (not that many actually) if you want to go that route.  Or if you have some vacuum caps, try that first before you buy a couple yards of hose...

[Grancoupe]

two things i would check is plug readings. The will give you an idea on mixture ratios. You might be running so rich that you at the breaking pint of when the engine is running at full temp and our drowning the motor. The ECU burning up could be a clue to bad grounds. I would temp wire a bunch of grounds and see if this clears anything up. Have you been through any fresh gas? By the sounds of it your not really getting much time on the road and even a hemi needs some mileage to eat up a full tank. Check fro fuel leaks internal in the throttle body when the notor is fumbling. See if there is a tolerance that is opening up in the carb when you getting heated up. Tail pipes sooty? Check for rich burning. Lean burning usually shows up more when you first start the car and gettsbetter asthe motor heats up. Rich burning usually gets worse as the car heats up. Only trying to help. Don't know how many of these suggestions you already got.
Would help if you made a list of what you already have checked to avoid repeats.

[nivvy]

Thanks  Yeah, i dont have an Orange box or anything.. I did just throw a cheap replacement ECU on there and it didnt seem to make a difference. Although, the old one was melted enough to see the 2 red tube looking thingy's. It was an NOS one I found a long time ago, been on the car 4 or 5 years.

hold on... ill get a pic of what you need,,,,,