It started last week.
Initially, when the car was cold and I started it, it would start right up and then stall. I would start it up again and run fine. Then on Friday the car initially started up and ran ok. Then after it got warm, it began having a really rough idle where you could tell it was about to stall any moment and stalled a few times. At mid to high rpms it still ran fine. Got it home.

Next time I drove the car was yesterday. I went out to the garage, started her up and ran beautifully all day. Today was supposed to be nice again so I decided to bring her to work again. Started up fine this morning other than an initial stall. Ran perfectly this morning. Went out at lunch to run an errand. Come out the car initially starts up ok...not great sounding but seemed ok. Then all of a sudden, the really rough / about to stall idel came back and the car began to consistently stall out at idle and low rpms. Pulled into a parking lot and only think I could to get her not to immediately stall out was by cranking up the idle screw to a point where it obvioulsy running rich from the smell. That was enough to get the car home. At most lights I would have to put it in neutral before I even came to a complete stop and rev the engine to prevent stalling again. Even at low rpms in gear it would occassionally stall out.

The engine is a 383 from Jasper and is only a few months old with a few hundred miles. I paid for Jasper to dyno tune / test the engine and when installed, it ran great. Now this....

Any ideas?

Unfortunartely, I am going on vacation in a day or so so she might just end up at a shop.

Thanks
Shane

 

Also forgot to mention....On the way to get the car back home today it was also surging pretty bad at low speeds / idle. Probably cuz I cranked up the idle screw I am guessing but did not want to leave that out.

 

man, lots of places to look.
Choke opening ok? stuck? Idle mix changed?
Check cap and rotor?
Plugs ok?
Vac leak somewhere, hose come off/cracked?

 

First ting I checked for was loose plug wire, issues with rotor or a vaccuum leak. Obvioulsy there could be a vaccuum leak somewhere I am missing but initial inspection showed up nothing. Also, choke was not stcuk and appeared to be functionaling normally
Shane

 

Do you have a new carb also?
Maybe some dirt in there that stops the gas sometimes?

 

Carb came brand new with the engine. Could possibly be from the old lines? Maybe dirt got in the lines during the install? Other gunk?

I will check the filter. Anything else I should look for?
Shane

 

What ignition?

Did you pull the fuel filter and inspect for debris?...metal shavings?
Pull the plugs and inspect them for fouling?...bad gap?

Elminate the free so you can spend $$ later ...then again; you might find the prob for free.

If you want; you can spray carb cleaner at key locations to check for vacuum leaks...I prefer DW40 because it dont take paint off (especially new paint)...same principal though.
Might just be a headlight vacuum loose, then connecting, then loose...
Pinched ignition wire, points/module,...ect....





GL




Jim




Inspect the free....

 

The ignition is an HEI MSD dist which also came new with the engine. Did an initial check for leaks and pinched wires and found nothing so far but def planning on trying the carb cleaner tonight.
More goodpoints....Thank you

 

For all it matters; you can plug/cap every vacuum line except the dist....then see how that is.
You definatly need to pull the plugs and let them tell you what to look for.
Fire and fuel...thats all there is to it.

There are a few threads on the MSD ignition probs....some sound very familiar.



GL



Jim

 

Sounds to me like ya got some water in the gas...try some dry gas...

 

I vote for FLOODING, the carb is getting too much gas....check fuel pressure, anything over 4 lbs is too much, beleive it or not, expecially if it's a Q jet....fought that crap years ago, I put a regulator in fuel line near carb and it was fine for years afterward.....

GENE