Camry 2.2CI Engine Stumbling

I would look for a split or disconnected vacuum line first. Wonder how you checked the sensors..Doubt its an injector, it would not "rumble" and it would not happen all of a sudden.

Thanks, I followed the repair manual and used an Ohm Meter to check resistances.

Would a clogged vacuum port in the Throttle Body cause this? I am asking because I followed a repair manual for one of the checks and found a weak vacuum when above idle.

I just had a similar problem, it started fine till hot then missed on one cilinder. I replaced plug wires , it fixed it. My 3 yr old aftermarket wires were crap.

I find buying most parts aftermarket to be suspect, For years my car would not get warm fast enough, I just replaced the thermostat with Toyota and what a difference. I tested the old thermostat it was fine but the gasket was smaller and narrower letting water bypass. I should have known when the mechanic said he had to use a lot of silicone sealant to keep it from leaking. Many parts are just worth the extra Toyota money to be sure your car runs right and the parts last. The parts stores answer to this was "we get them as cheap as we can" Problem is, no quality control, so who suffers, the consumer, us.

Aftermarket wires usuallu are. I learned a long, long time ago, use genuine Toyota (er, Sumitomo?) wires. I did a complete tune up using off the rack parts, and the car ran like crap. So 3 weeks after I did the tune up I bought real Toyota wires and only got 150,000 miles out of them.

Would have thought I had learned, since on the same car i did a tune up with genuine Filko parts (they're out of business, right? ;) and the rotor arm blew the brass contact into a dozen little brass balls in the base of the distributor. Genuine Toyota after that...

Would a clogged vacuum port in the Throttle Body cause this? I am asking because I followed a repair manual for one of the checks and found a weak vacuum when above idle.

---------------- Certainly possible. I've got the 1994 Camry 4 cylinder. Recently changed the idle air control valve, and followed the procedure in the Factory service manual for removing and cleaning the throttle body with carburetor cleaner and compressed air through the three vacuum ports that feed the EGR modulator, located just beyond the closed position for the throttle butterfly valve. The first port has a very, very tiny orifice. Gunky brownish black residue came out when blasted with compressed air as shown in the diagram. That was at 126,000 miles always using good quality name brand gasoline. However, I may also have had incomplete combustion for some time, similar to your comment about a sooty spark plug. One of my original plug wires had been shorting to ground inside the spark plug tube where it was not visible.

one plug showed soot

------- That's your clue. You need to correct the problem in the secondary ignition system.