I have seen this issue before, and if they came to that conclusion then they must have already tested the pump, lines and valve operation, then checked the flow of the actual passages in the heads. The passage ways in the heads can get clogged with carbon, and the only real fix is to remove the heads and run brushes with solvents etc through all the passages. If this happens to my X I'll be running the cleaning brushes in as deep as I can go through the front main passages and trying to flush out the secondary passages with some potent solvents, (soak, then blow through) but you'd still have to remove the exhaust headers to avoid blowing all that trash in the headers...

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"When you do things right, people won't be sure you've done anything at all" (Bender, futurama)

You make something idiotproof, they'll make a better idiot

You think professional is expensive, just wait until you pay for amateur.

Never let your sense of morals prevent you from doing what is right.

Examine what is said, not who speaks.

X5 pics

RIP 4.6is.....

2003 4.6is