One thing after another goes wrong
 

Have a 2002 Camry SE V6. A couple of months ago, the check engine light came on and the codes were for the O2 sensors. They were replaced. Shortly after that, check engine light again, this time, cat converter. Had that replaced, Now another check engine light, indicating a bad knock sensor. Car runs great, no loss of power, etc. Then yesterday, the instrument cluster went dead. I reset that but is still not working correctly. I am now wondering if it is the ECM is failing. I get one thing fixed and another pops up.
Any thoughts?

A bad ECM can trigger the check light. However these check engine indicated problem parts can be tested. An ODBII scanner can also provide signal outputs to compare with normal.

A failed ECM tends to result in engine performance issues and hard starting.

What failed on the instrument cluster?

Problem wiring can also cause issues.

This link matches what happened to my instrument cluster exactly. I use an OBD2 scanner as well as the mechanic at the shop I take my car.
One code is taken care of and another pops up.
The car runs great and has no starting problems.
Right now the code from the scan is P0330 which is a knock sensor on bank 2.

The cluster issue appears relatively common. Have not found a permanent fix other than replacing the unit. Toyota has nothing on this problem.

Suspect it could be bad solder joints or failing capacitors, but you would be on your own in diagnosing.

It has happened the A/F-02 sensors have issues. Then when fixed the CAT is found bad. These sensors do monitor the CAT's performance.

The P0330 may or may not be the sensor.

The sensor is buried under the intake manifold and would be time consuming to get to.

Does the mechanic have access to detailed repair info and the test equipment to check more detailed then the scanner?

Might pickup a set of factory shop manuals. Ebay sells used ones or try searching the net for pdf files. Toyota does offer access to shop manuals for a daily rate.

The manual would have more detailed info on diagnosing the knock sensor code. And all codes for that matter.

It is possible to run tests for most components. This rather then just accept the trouble code generated as the final say.

It gets weirder and weirder. Drove the car and most of the instruments works now. The door open ding does not work although it did right after the reset. The park and reverse lights do not work. Odometer does not work with the headlights on. Turning the key on and the speedometer, tack, temp, and fuel gauge goes to max for a few seconds. I have a cluster on order. Had to get a used one and got a 6 month warranty with it

If I were younger, I would get the manuals and do the work myself to find the P0330 problem. The V6 is too hard to get to everything. I don't think my mechanic has the know how to determine the root cause. He is mostly a domestic auto mechanic. And I sure hate to take it to a dealer. The cost is prohibitive.

I will install the cluster when it gets here and keep driving with the P0330 and clear it when I take it in for inspection. Like I said, it still runs great.

Suggest checking for wiring issues.

If clearing codes for any inspection which taps into the OBDII to scan the computer for problems. Don't clear the computer completely. Most states will not pass a car until a specified number of self checks are completed by the computer. They may allow up to two checks to not be completed.

Its possible to operate the car just fine with this knock sensor issue. Some owners have even cut the old sensor off the wiring and installed another sensor elsewhere.

If going this route do some research. One issue is the wiring is shielded, another is where to locate it. It needs to be bolted to the head somewhere to generate a signal caused by the engine operating. Assuming the issue really is the sensor.

Hello, new member here.
I recently bought an 02 Camry for my son to drive for his first car. Since buying it used for $3000.00 I have had to put front brakes pads and rotors in, new tires, and the day I was taking it to get the tires put on the CEL came on with quite a few codes. Had to have the Catalytic Converter replaced for $525 and still have P0440 and P0446 Evap codes to deal with...Just taking a breather from spending money on this car for a bit here now. All my friends told me to buy a used Camry, "they don't break down"...Maybe they don't but I am finding that when they do have issues they seem to be major and expensive. Glad I bought the car at a good price and it's in pretty good shape. Nice enough that it's worth keeping up and investing money in to I think.