I had the 350 swapped into the 91 Caprice 4 years ago it was from a 1992 C1500, it ran good the whole time, recently in the winter time it was close to about -30c and I hadn't plugged the car in overnight. When the car started it sounded like a tractor really high idle, I changed all my spark plugs, distributor cap, rotor, ignition coil, coolant temperature sensor, fuel filter, spark plug wires, intake air temperature sensor and EGR valve. The map sensor had been changed just a couple months before I got the engine changed 4 years ago. After replacing everything and scanning the OBD1 I don't have any engine codes and the car continues to run bad but not at such a high idle. I'm wondering if anyone knows what it could be. I'm currently replacing my throttle body gasket and the fact occurred to me that I have 305 injectors on the 350 and the ECU and the TBI unit had not been changed when the engine was changed. The TBI units were kept to there same vehicle for Hood clearance reasons. I tested the TBI injectors with a 9-volt battery and they both make the clicking sound. I'm wondering if the ECU could also be damaged from that. Also if I need to change my injectors to the 350 ones.
I don't have any vacuum line leaks but I am wondering if it could be intake manifold gasket. It bogs out and dies under acceleration especially in drive and reverse. When it is in park or neutral I can rev it more, like it is an underload issue? It still does not sound like it's running normal like it did about a year ago from now. THX
I don't have any vacuum line leaks but I am wondering if it could be intake manifold gasket. It bogs out and dies under acceleration especially in drive and reverse. When it is in park or neutral I can rev it more, like it is an underload issue? It still does not sound like it's running normal like it did about a year ago from now. THX
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