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After getting my car back from mechanics new codes popped out:
P1346 and P1351 -- timing is off on both camshafts?
Btw, I explicitly asked them to change the foam gasket for both covers of timing belt. Check this out, there is no gasket at all:

P0125, P1135, P1155, P1130 and P1150 -- O2 sensors. O2 sensors are new. Probably due to a NEW crack on the front exhaust manifold:



Bank 1 O2 sensor is loose:



Besides this lots of scratches, loose bolts, loose wires and missing parts:

 

Also it was low on coolant. I just added about a gallon of water in radiator and extension tank.

 

wow thats not good at all. I would say take it back but look at the work they did in the first place. good luck.

 

My opinion................., that was just plain carelessness. Especially the gouging and scratching. I sincerely hope the internals were treated better.

 

When my uncle, cousins and I install engines, a common CEL to get is timing error, it usually takes some adjusting and rechecking over and over.

 

They told today that the exhaust manifold cannot be welded and needs replacement. BS. Anyway I am NOT paying for this.

 

For sure that is BS, too bad you ain't down here, my uncle, I or my exhaust shop could weld that sucker easy.

 

I know, but I meant "I am NOT paying for it." I was trying to imagine how them are gonna pull that manifold out. The radiator support is on the way on top... Did you weld yours while mounted?

 

Yes, quite easy.

 

Since we need to take it off the engine, are there any gaskets? I assume there are because steel-to-aluminum contact will lead to galvanic corrosion. Do you think they are reusable?

 

There is a gasket between the manifold and the engine block. I don't know specifically about the RX300 from experience, but with other vehicles I have worked on at my uncle's shop, we resuse them.

 

I am getting the P1346 code after timing belt replacement but the engine runs like a clock. What can be done to prevent this code?? What do you mean by "adjusting and rechecking over and over?"

 

In my case the problem was non-standard cams, they replaced them again.
Of course, they also had to redo the timing belt.

But in your case the problem is the timing only on the rear bank. They did not put the belt correctly. Ask them to redo it. It is 100% their mistake.

 

Actually I replaced the belt myself. The rear camshaft sprocket did turn during replacement of the belt. I turned it back to original position and the engine runs fine. I just need to find out what needs to be done to prevent the ECU from giving this code.

 

Ok. There are adjustment marks on the lower timing belt (crankshaft) cover and camshaft pulleys. They need to match. Even if one of them is off by one teeth, ECM will detect it. After you think they match, make 2 revolutions of crankshaft (manually of course, better remove front spark plugs to help fight compression), recheck and readjust until everything is matching while under directional tension. Usually adjusting a V6 timing is a two-man job. You did it yourself?

Good luck. By the way, 1MZ-FE VVT-i is an interference engine, so be careful not to hit valves with pistons.

I am just curious how did you manage to loosen crankshaft bolt? You have tools or you did it with a long bar and the starter?