Check compression. If you have low readings in two adjacent cyliners you may have blown the head gasket between the cylinders.
I replaced plugs, wires, cap and rotor with no improvement...I know it's probably a stupid question, Russ, but I'm going to ask it anyway. Have you taken a good look at your rotor button and plug wires under the cap? Sometimes the wires get pitted and need to be rotated 180 degrees to the better contact side. Just replace the rotor button with a new one. They're cheap enough. Heck, for all I know, you may have an extra one around there already.
I have checked timing several times during all of this, and it holds where I last set it. In this case, it's at 12.Also, might be a good idea to recheck the valve timing. When you replace a belt before it breaks, it's hard to be off, but after a belt breaks or slips, there is the possibility of not aligning the marks correctly.
thanks John...will watch for bubbles in the coolant tonight when I work on it. I see your point about the o2 sensor. I will recheck for codes also.A compression test may be inconclusive for many of the 2.5 HG failures simply because the failure is often just a hairline crack in the steel fire ring. The cylinder may pass the compression test, but a small amount of combustion gas can pass through to the cooling system passageway adjacent to the cylinder. Likewise, when a warmed engine is turned off and the cooling system is still pressurized, a drop or two of coolant can pass through a split HG and get into a cylinder. A compression test to diagnose a ruptured gasket would certainly show a problem but a ruptured gasket is usually not the typical 2.5 HG failure.
The best test is to use a product that detects combustion gasses in the coolant overflow container, unless you already see streams of bubbles present in the container; then it is pretty obvious.
Sometimes the HG hairline fractures that show up in the fire ring (that surrounds the cylinder) are so small that they don't cause noticeable leakage until the engine has warmed up. When I am checking for the HG problem, I watch the overflow container right after starting the engine when it is cold and continue to watch for 15+ minutes while the engine fully warms up. Of course, you must make sure that there was no air in the system from any previous work where the system had been opened.
Keep in mind that any coolant that has passed through the exhaust may have poisoned the O2 sensor which will cause a bad running engine.
No, Russ, I meant the valve timing, not the ignition timing. The relationship between cam, crank and intermediate pulley marks when you changed the timing belt.I have checked timing several times during all of this, and it holds where I last set it. In this case, it's at 12.