Again, here I am with something regarding my 1987 Fifth Avenue with the
318/2bbl and "LeanBurn."I removed the carb and intake the other day and cleaned out all of the passages. There was a bit of black goo in the EGR passageways, but nothing that stopped it completely up. Either way, I soaked the intake in parts dip and everything looks new now and is clear as can be. Got it all reinstalled and took the car for a test run. It still has the surging and stumbling, whether or not I'm under a load (ie: driving the car) or just revving the engine in neutral.
Okay, so... Just for the hell of it, I pulled off the vaccum line going to that vaccum modulator on the aircleaner.... You know, the one attached to the LeanBurn computer. At idle, it didn't make any noticable difference in engine performance, but as I revved up the engine, it was SMOOOOOOOTH! Smooth as can be and stayed smooth! No stumble, no surging! So I left the modulator disconnected (vaccum line plugged) and took it for a short drive. Once again, it accelerated smooth as can be and took off like a rocket without hesitation or stumbling. So under load or in neutral it runs GREAT with that line disconnected and plugged.
It shocked me how smooth it was.
SO, what the hell does that vacuum modulator tell the computer? I didn't feel like tearing into the computer housing to see what it was attached to. I'm ditching LeanBurn come this summer and converting to standard carb and electronic ignition, but in the meantime can I leave that modulator disconnected without hurting the engine? It's not going to cause me to run too lean and hot or anythng else horrible? The smooth performance I gained was really quite spectacular.
Thanks,
-Steve