A flashing check engine light usually indicates a misfire. You need to check codes to know possible causes.
That REQUIRES an ENGINE SCANNER to do that.
I have the check engine light on and the code is for map sensor on my 1999 1500 Chevy suburban
See link below.
The engine computer has detected a malfunction and set a code.
The 1998 Chevy Express 1500 Van could have the 4.3, 5.0 or the 5.7 engine.
The crankshaft sensor is located in the engine on a Chevy 1500 truck. This is under the hood.
5.3
Where does the vacuum line lead to from the top of an 2002 Chevy express 1500 van with 5 liter engine
35- idle air control (iac) valve/ circuit
The 1998 Chevy Express 1500 Van could have the 4.3, 5.0 or the 5.7 engine.
The EGR valve on a 1994 Chevy 1500 is located on the top of the engine. If the valve becomes stopped, the engine could idle rough or stall.
That requires an engine scanner.