'92 LSX Troubles after rebuild

[wondermelon]

i got the car when it was in the process of eating a rod bearing. since then i've replaced rod and main bearings, honed the cylinders, put in new rings, and had the head rebuilt (including new valve guides, so they say).

my main problems are:

-engine makes rattling noises at idle and while accelerating and decelerating up to 3000 rpm or so. for a short range it also makes a reed-like noise.
-not a lot of power below 2000 rpm, engine runs poorly at WOT in this range. power really picks up after 3000 rpm (ignition timing maybe? i haven't adjusted it at all)

other random parts replaced:

-junkyard FPR (old one seemed to be leaking through the vacuum port)
-replaced cracked exhaust manifold
-new o2 sensor and flex pipe
-junkyard MAP sensor

I'm starting to get really stumped here... anyone have any ideas?

[Donald]

I am guessing this is a Prism!?
What engine?

[wondermelon]

sorry for not mentioning, it's a 92 corolla with a 4AFE

[retiredat44]

how as the piston and wrist pin on the piston that had the rod bearing go bad? maybe that piston and wrist pin were bad from the bearing knock..

[Donald]

Who did the measuring and reassembly? Was it you or a shop?

What I am leading to is, are you sure proper measurements were taken of the crank journals and bearings?

Has the timing been set correctly?

[wondermelon]

Originally Posted by retiredat44

how as the piston and wrist pin on the piston that had the rod bearing go bad? maybe that piston and wrist pin were bad from the bearing knock..

i did not personally measure them, but i took in the pistons/rods into the same machine shop who honed the cylinders and polished the crank. they cleaned and inspected them, and said they were fine.

however i think you could be right.

Originally Posted by Donald

Who did the measuring and reassembly? Was it you or a shop?

What I am leading to is, are you sure proper measurements were taken of the crank journals and bearings?

Has the timing been set correctly?

I did the reassembly but a shop measured all the journals and said that everything was fine. also i just removed the oil pan and checked all the rod bearings. they look fine.

ignition timing has not been set as i don't have a timing light. cam timing looks to be spot on.

[Donald]

I would get the timing checked.

If the crank was polished, you or they should have plastigaged the bearing-to-crank gap.
Do you know how to do that?
That would be my next recommendation.

[wondermelon]

Originally Posted by Donald

I would get the timing checked.

If the crank was polished, you or they should have plastigaged the bearing-to-crank gap.
Do you know how to do that?
That would be my next recommendation.

I did ask the guy at the machine shop if he plastigauged the crank. he didn't know what a plastigauge was . They seem to do things more "by feel" around here.

I think the main and rod bearings are ok. Since the mains were never a problem i didn't check them when the oil pan was off (though i did replace the bearings during the rebuild). And the crank bearings looked fine after i rechecked them.

I took my car to the Toyota dealership today. Tech says "LISTENING TO BOTTOM END AND CANT HEARD MUCH BUT LIFT VEICLE UP AND SOUND LOUD SND CLEAR FROM OIL PAN AREA,MANY POSSIBILITIES ,BEARRING,CRANK AND OR LOUDER FROM #2 AND #3 CYL."

So I think that narrows the clattering noise down to two possibilities, wrist pins or piston slap. It seems strange that the noise is coming from the middle two cylinders.