Catty Installed... Now Why Will It Not Idle?

[Bronto]

Hi

Just purchased a 94LS400, (240k for $1200) installed a vacuum tube (basic tubing) ,new catty, one is the original. Now it won't idle properly.

Issues:

*Putt,putt, almost choking sound after firing up..Sometimes won't fire up.

*While terribly idling, it dies when trying to shift gear..

Questions:

Could it be as simple as the air filters (cabin&engine) causing this??

Or does this sound like a more severe issue?

Is ANYONE in NC, near the triangle?

Bronto

[steve2006]

Did it work OK before you replaced those parts?

[Daniel091]

Fuel , spark and timing?

[Bronto]

I don't know, I purchased it as-as. The seller fired it up, and it sounded like a tank,b/c of the unattached cattys so to me, just installing those would cure it... I spoke to a guy today that said it could be a idle choke or a vacuum issue b/c its shutting off pretty swiftly

[pj8708]

You say it "sounded like a tank" when the seller started it. Does that mean it was just loud or did it run rough?

If it ran alright at that point, but not after your work on it, it would seem logical to work backwords to your original starting point.