I think you're right on target. I checked compression, and all cylinders fell between 175 and 180, so it wasn't a burnt valve.
At the suggestion of an AlfaBB member, I pulled the idle jets (which is pretty easy) and blew them out with compressed air. The car now holds an idle and seems to be running normally. The fuel pump filter bowl showed no signs of water or debris, so I doubt it was a load of bad gas, but who knows. If it happens again I'll take a more thorough look at other areas of the idle circuit. Dean Mericas Austin, TX 1965 TR4, 1974 2000 GTV, 1976 Giulia Nuova Super 1300 -----Original Message----- From: skip [mailto:[email protected]] Sent: Tuesday, May 25, 2010 10:09 PM To: [email protected]; Alfa Digest Subject: Re: [alfa] Idle and running problems - any idea what's going on? Hi Dean, It sure sounds like some kind of a gremlin has invaded the idle circuit on one or both of your carbs. The idle circuit not only controls fuel flow at idle, it stays in play for at least the first 1/3 throttle opening before it finally tapers off. So, water, dirt or almost anything in a passage way, jet or mixture screw opening can cause this problem. You will probably have to open the carbs and make sure everything is clear but you might just be able to blow compressed air in the idle mixture screw holes and blow it out at least temporarily. If you filled the fuel tank just before this happened you might have picked up some water. Skip Patnode '67 Duetto Norfolk, Va Date: Mon, 24 May 2010 0:22:59 +0000 From: <[email protected]> Subject: [alfa] Idle and running problems - any idea what's going on? I am wrestling with a running problem with my Super, and am now reaching out to this forum for ideas. The car is a 1976 Giulia Nuova Super 1300 with twin Solex ADDHE carburetors. Up until yesterday, it was cold to start, but ran like a champ when warm. Yesterday, the following symptoms appeared: - - Engine won't hold an idle, even when fully warmed. I can only keep it running by blipping the throttle or pulling out the enrichment knob. Otherwise, it just slowly dies. - - Engine misses erratically at part throttle cruising speeds. Acceleration with full throttle is smooth, although it may be on the weak side. Following the theory that 95% of all fuel problems are electrical, I checked the plugs, points, rotor, etc. Everything appears to spec. Spark plug tips are uniformly light tan, maybe even on the whitish side. I can't imagine what other electrical component might be causing the problem. I don't think its fuel supply because the problem is worst at idle and the car accelerates OK. Nonetheless, I checked the fuel filter and cleaned the element. No debris in the glass bowl and the filter is relatively clean. I blew it out with compressed air, and am ordering a new one, just in case. All of the above made no difference whatsoever. Now I'm thinking its a vacuum leak. I checked the brake booster, and it's got good vacuum in the line 15 minutes after the car is turned off. What I am missing here? Cracked carb mounts? Something even more esoteric? Help me! Thanks. Dean Mericas Austin, TX 1974 2000 GTV / 1976 Nuova Super 1300 / 1965 TR4 -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected]
