Hi

My dad has a 2001 toyota camary 4 cyl. The exhaust is cherry red where the manifold meets the ehaust. We pulled a coide p0300 random missfire detected. Any ideas?

 

These code has a LOT of possible causes over a very wide range. Suggest a Google search under the words Toyota or Camry and the code number. The results will be many hits, run through the sites that come up to get an idea of of the problems and fixes.

If you have the code info for one Toyota engine, you will have a good idea of what problems are possible with your engine model.

A few possibilities:

Vacuum leak. Look for loose or damaged hoses that run to intake manifold.

Engine at idle an unlighted propane torch can passed slowly around the engines vacuum, throttle body and intake manifold areas, if a leak is present the gas will be drawn in and the idle will change.

Exhaust system plugged, bad emissions converter, plugged muffler, etc. A vacuum gauge connected to the intake manifold will check for excess exhaust back pressure.

Ign timing is off.

How does the engine idle and other wise operate? If it idles OK and other wise runs OK this would suggest no air leaks or timing issues. How is the engine power, a plugged exhaust will cause loss of power.

Remove the plugs and check for electrode condition. A Google search on reading spark plugs will produce hits with photos. Too lean or rich will show up on the plug condition.

If you are up to it, there are ODBII code readers having real time output to allow monitoring the various sensors and systems. By monitoring the engine as it runs you will see if the fuel system is trying to compensate for a lean or rich mixture caused by an air leak. If the timing is off, or the ign system really is misfiring (again the list of causes is long an may not be connected to the ign system).

If the car otherwise runs OK would guess a plugged exhaust system, the converter.

There is a TSB out for this code.

http://www.justanswer.com/uploads/sk...camryp0300.pdf

 

Hi Joey

We suspect a bad cat. However im relucant to put a new cat in until we identify what caused the problem. Could we punch out the bad cat and then troubleshoot the problem?

Jim Hey

 

You could but as cats are expensive before doing this do a google search on using a vacuum gauge to troubleshoot a plugged exhaust system.

Or remove the cat.

Used to be able to by a "test pipe" that would replace cat for low cost but the price appears to have greatly increased.

Or jury rig a section of flex pipe into the exhaust to replace the cat on a short term test.

 

how close is fuel tank to that exhaust pipe?

 

I have a good read on this article

Toyota Repair: Code P0300 and P0303, camry v6, head gaskets

maybe that can help.