2000 HONDA CRV, MISFIRES, WHEN COLD?

I HAVE A 2000 HONDA CRV. I RECENTLY HAD A WATER PUMP AND TIMING BELT REPLACED ON IT. NOW IT MISFIRES WHEN IT IS COLD AND RUNS FINE, WHEN IT IS WARMED UP. IT RAN FINE BEFORE I HAD THE TIMING BELT AND WATER PUMP REPLACED. WHAT COULD BE WRONG?

Maybe the spark plugs or wires, maybe even the coil packs.

I would do an engine vacuum test and have two readings: One is at idle and the other is at 2000 rpm. What are the readings?

The second test would be the engine cylinder leak down test: What is the reading (Percentage) for each cylinder?

Have you have the code(s) read out? What is/are the code(s)? If the engine idles roughly, is hard to start, or has the MIL on with DTC P0301, P0302, P0303, P0304 (cylinder misfire), or P0172 (fuel system too rich): The valves may be too tight and need to be adjusted.

If the clearances are within specification, look for other possible causes (ignition, fuel injection, etc.). If all checked out good then older CR-V (1999-2001) has had a problem that one or more exhaust valves have receded into the cylinder head. Honda issued a TSB # 03-038 dated NOV. 05, 2004 addressed that problem.