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I purchased a rebuilt PCM from them for $249.00. I came programmed and worked like a charm

 

well on final look i read alloros post and checked the compression. i did manage to confirm it was a 2001 v6 computer in the van, and the fuel pump works 47 psi. but halfway thru the compression checks it was time to take landyachts advice and pack up the tools and walk away.

cylinder number 5 dry 156, running 120
cylinder number 7 dry 150, running 87
cylinder number 6 dry 180, running 120
cylinder number 8 dry 180, running 90
dont know which ones are even close to right but didnt bother to fight my way in to the front half plugs as i am sure there must be something wrong with this engine to have this much disparity between the sides of the engine. thanks for all the input but back to shopping

 

I can not/ will not claim to be a compression testing guru, and have never performed a leakdown test.
My impression of the leak down test was that one checks the compression normally on one cylinder, then removes the tester, squirts 10w30 or thicker on and around the piston, then performs the test again. A huge improvement of the compression after this test would point to worn rings or cylinder walls.

If there were a hole in a piston I cannot imagine there being any compression on that cylinder, before or after squirting the piston with oil. A cracked piston perhaps.

I have never heard of checking compression while an engine is actually running. When I did the procedure, I disconnected the coil wire and just used the starter motor and batteries. Not good for the starter motor or batteries though.

 

much research on the forum and internet led me to the testing. you are referring to what has been called a dry and wet test. as i have read it is exactly for testing worn piston/rings. (the "wet" oil part) i have additionally read during my research that a third compression test with the engine running should result in a correct compression reading of 50-65% of "dry" compression reading. as i foolishly forgot to bring s squirt bottle of oil along i could only do the dry and went ahead and tested the engine running on each easily accessible plug. i have not substantially gathered exactly why to test the plugs running or even why it is only 60% of the standard compression but the posts read -- (x range) compression dry, test wet, test running 50-65% of dry, should not be a variation in excess of 10% of the compression value from one cylinder to the next i.e. 150 psi on #1 then #3 should be within 10% of that (something to do with trouble shooting head gasket/head etc. but none the less these 4 cylinders were all over the map and not even close to what i read was recommended.