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Sniady-

NO NO NO!!!! Guilty of Alfa abuse. Sentence . . . 10 lashes . . . well laid on. Do not mess with the SPICA FI system unless you know what you're doing. It's not so complicated that you can't read for a couple of hours and understand it well. Get into the book.

There's a reason is running fast.

1. Check that the throttle cable is not holding the throttle off the idle stop when the engine is at running temp (170 minimum). If the knucklehead PO adjusted the idle cable tight with the engine cold, then it would not allow the throttle to go all the way to the idle stop when hot.

2. If the throttle cable is correct, on the back of the injection pump, check to ensure that the distance between the idle reference screw and the throttle arm is no more than .019" when the engine is hot.

3. If it's larger than that, then the thermostatic acutator is probably malfunctioning. The TA extends a piston in the injection pump as the engine heats up and commands the mixture to decrease in richness (pump throttle arm to go closer to the reference screw). The engine MUST get to at least 170 degrees. If it doesn't replace your coolant thermostat. If you suspect that the TA is bad, get the engine up to operating temp, carefully remove the center bracket of the thin brass tube, then remove the two small screws holding the actuator in the top of the pump. DO NOT KINK THE BRASS TUBE. There's a small chrome piston that should be protruding and it should be about 27-31mm from the end of the piston to the base of the flange plate, depending on the year of manufacture. You can also remove the whole TA and test it in a pan of heated water and a thermometer. If you need a rebuilt TA, they're about $200. The salient part here is that the "pump gap" (between the reference screw and throttle arm be no more than .019" when the engine is hot. UNDER NO CIRCUMSTANCES REMOVE THE PLASTIC CAP OR SAFETY WIRE, NOR CHANGE THE SETTING OF THE REFERENCE SCREW ON THE BACK OF THE PUMP. NEVER! NEVER! NEVER! NEVER!

At hot idle, the only air the engine should get should be through the idle circuit and that adjustable tube. There is a rubber O-ring behind the threaded pipe that is pinched. When it's pinched, it narrows the hole that the idle air must go through, thus changing the idle speed a small amount. Replacement O-rings are available from Centerline, et al for about $2. You may check to ensure that there actually IS an O-ring in there to begin with and that it's pliable and not hard/cracked. You never know what PO's did to the car. That idle speed adjuster is not going to get the engine up to 1700 rpms.
 

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Yea, I know that was you Alfa_Chan. Before you told me about it, I hadn't thought about it. We'll . . . . I just "assumed" . . . . and you know what that means. Anyway, "throttle cable" is now an early step in my SPICA troubleshooting guide.

Sniady - There is no choke on an SPICA system. I think what you're refering to is the pull cable on the lower left rear of the center console. That's a "hand throttle." All it does is pull the throttle cable back a little so you can set a throttle position without pressing on the accelerator. It's ONLY function is to help keep the rpms up a little when the engine is cold and warming up. It is NOT a cruise control and should NEVER be used while the car is in motion. It DOES NOT release when you press the brake pedal like cruise control systems do.

To check to be sure it's not restricting the foot throttle, look where the cable goes through the firewall (center left side of the firewall, then goes through a loop on a tang attached to the throttle actuating bar (that's pivoted on the firewall). With the hand throttle pushed all the way in, it should be loose on the throttle bar and not preventing the manifold butterflys from going to full shut (engine hot). Since you say you've already checked the throttle cable (there should be just a bit of slack allowing the throttle bellcrank to go against the throttle stop screw), then the hand throttle is probably not set too tight either.

I think you're down to a grossly maladjusted idle stop screw (unlikely, but possible) or a bad T/A.

In a SPICA system, the Thermostatic Acutator acts as a choke would in a carb engine. However, it does NOT restrict airflow in the intake like a carb, but rather mechanically enriches the mixture as well as opens the throttle slightly to provide a higher cold idle. As the engine heats up, the TA piston retracts and the FI pump throttle arm returns to the reference position (.019" clearance). This also closes the throttle butterflys back to full closed so the ONLY air the engine is getting is through the idle system (small hose from air cleaner to manifold, then the 4 even smaller hoses to each cylinder barrel).

Do not go and start "adjusting" anything like idle stop screws, etc. What we're doing right now is just checking the operational integrity of the most likely suspects in your high idle problem.

If the TA checks out good, then a complete reset and tune of the SPICA system is probably in order. That's going to require a lot of reading and understanding and a nice Saturday afternoon . . . no beer until job is finished.
 

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The rubber O-ring in the equalizer only costs about $2 and are available through Centerline or IAP, I think.

If you convert to carbs, don't toss ANY part of the SPICA system . . . and be very careful when you dismantle it NOT to break anything, especially the TA.

I guess I'm a purist, but I generally like to keep them in original condition, including the SPICA system. Design-wise, it's a work of art and machining-wise, it's difficult to find something as finely made as a SPICA injection pump.

Someday I'd like to get a Spider and do a high performance street mod to it. Unfortunately, I'm out of garage space and I'm not sure my wife would take kindly to having her car evicted from the garage by ANOTHER Alfa. On the other hand, it may be worth just doing and appologizing afterwards. . . . . . . .
 
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