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In what order are these to be performed? AC and ISC

2K views 20 replies 3 participants last post by  firstimecaddi 
#1 ·
OK I have these issues all of which I think are related to A bad ISC motor. I even had the code PO30...ISC slow or inoperable.

Recently, I had the "Refrigerant Low....AC off message" with the accompanying code AO47.

I have a new ISC to install and a can of refrigerant to recharge the system but...

...for the AC to be recharged the engine has to be running, and for the ISC when it is replaced it has to be relearned. The relearn procedure though, requires that the AC to be on for a part of it.

As things start right now, if I get the car to start the idle speed in Park is 1000 rpm or greater, when in Drive foot on the break it falls slightly to 8/900 rpm.

So how should I approach this?
 
#14 · (Edited)
ok I got both items done today...AC took all of a 12oz can of refrigerant and is cool again. Replaced the ISC motor and set the gap according to the above guidelines. Everything seems good so far. It idles at approx 6/700 rpm in P or D smooth and steady. When it is first strarted though, the rpms are as much as 1000 for a bit....then it gradually drops to 6/700.

I took it out on a short ride, but was disappointed with the fuel consumption. Used 1.6 gallons over 28 miles at 70 mph? Plugs, wires, fuel and air filters are newly replaced. I think something is still amiss. This car used to average 22/3 mpg on the DIC, these days it is 19.8/20. What might I be overlooking?
 
#15 ·
When it is first strarted though, the rpms are as much as 1000 for a bit....then if gradually drops to 6/700.
As it should be.

I took it out on a short ride, but was disappointed with the fuel consumption. Used 1.6 gallons over 28 miles at 70 mph? Plugs, wires, fuel and air filters are newly replaced. I0 think something is still amiss. This car used to average 22/3 mpg on the DIC, these days it is 19.8/20. What might I be overlooking?
Leaky FPR?
 
#20 ·
OK, in that case disregard the above. You will have to remove the (functional) manifold cover. Inside is where you'll find the fuel rail and FPR. Since the FPR is subjected to manifold vacuum, there is no need for a vacuum hose. The nipple will simply be exposed. :)tisk: I know what you're thinking). Go to KOEO (key on, engine off), but DO NOT CRANK THE ENGINE. KOEO will energize the fuel pump and pressurize the system. Just like above, look for fuel leaking from the nipple.

P.S.
Be sure to use the proper torque specs when reinstalling the manifold cover. It does not get tightened real hard. It has to be able to lift in order to vent the manifold in the event of a manifold over pressurization (backfire).
 
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