Help! 1982 corvette keep stalling

[TBone5330]

I have a 1982 corvette that keeps stalling out when I am driving it and when the ac is turned on. I live in Cave Creek, Arizona and was in the process of restoring the Vet. I did not use the a/c at all because it was cooler outside. I had a lot of work done along with replacing the engine.

It was replaced with a 30-19355658 SBS 4 bolt main, 2pc R/Main 300HP+ @347 ... Torque rating Long Block (This is what the paper says). Work done at same time; Intake manifold, Oil pump, Intake Gasket, Valve Cover Caps, Pan Gasket, Oil Filter, Fuel Filter, R111638 Alternator, A/C Temp Relay, Knock Sensor x2, Spark Plugs wires, Omni Spark Plugs, EGR Valve, Thermostat Gasket, Thermostat, Distributor cap, Distributor Rotor, Freon A/C, A/C Compressor Can, Coolant hose, New Radiator, Harmonk Balancer, Water pump, 17-1002 P/S Cylinder, Flowmaster exhaust + a lot of smaller other items..

Right no in the heat when you start the car it idles ok, but once you drive it and stop it stalls out every time with A/C on and sometime with out the a/c on. I have it at a mechanic right now and they replace a sensor that now shows the system to be closing but they said the alternator keeps draining the battery so they only have so long to work on it before they have to recharge it. Can anyone please help. I may be missing some important info so please ask and I will see what they tell me.

[h=1][/h]

 

[Tom Bryant]

With an electronic ignition you need a full charged battery and a working alternator to keep it running. Looks like the first thing to do is fix that charging problem. Your ECM should increase your idle speed when you turn on the A/C. It could be a simple as that it hasn't been driven enough since the rebuilt for the ECM to learn the new perimeters since the rebuild. Is it throwing codes?

Tom

 

[Hib Halverson]

Provided the fuel system and the ignition system are in good condition...if that engine has a camshaft more aggressive than the stock cam, I'm going to take a wild-assed guess and suggest that the ECM calibration is not optimal for an engine with that bigger cam, and the problem is most obvious at idle under the HVAC compressor load.

On the other hand, if the fuel system and ignition systems are not in good condition, you need to address that issue first and throwing sensors and other parts at the problem will be a very expensive proposition.

On the fuel system, you need to find a service facility familiar with maintenance and tuning of the 2xTBI system used on '82s.

 

[KANE]

That engine is basically an L82... your L83 had a cam that was .410" / .423" (if I recall) where your new engine has a .450" / .460" cam.

Basically... your OEM ECM (and chip) is NOT going to give that engine what it needs for a VE table. Hypertech and others won't do either because their VE tables, AE tables, and other parameters aren't matched to your cam.

That's why it's not running correctly- the fueling isn't correct for that cam. And, no matter what you do... it won't be right without getting the correct VE tables in an ECM.

Good news- you can replace the ECM with a later TBI ECM - along with the terminals to the ECM- and you can find people to burn a TBI chip that will likely work.

Your OEM intake needs to be ported out. That engine's torque peak out higher than stock and produces more HP at a higher RPM. The ports on the intake that meet the head are too small- they can be opened up though. Use an intake gasket as the guide.

You will likely need to adjust the fuel pressure.

All that said, you'd be better off getting Dynamic EFI's EBL Flash ECM, a wideband sensor, TunerPro5 to adjust BIN files, and teaching yourself to tune.

Modding a CFI isn't terribly hard- modding it the right way and getting the tune right is an investment of your time (or someone else's).