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lean LS7, should I be concerned?

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Old 07-25-2008, 04:36 PM
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Default lean LS7, should I be concerned?

I have a after market fuel tank that feeds my LS7. Occassionaly I have a drop in my fuel pressure from 58psi to 20psi for a few seconds or less, then last week I had a drop to almost zero and the engine shut down of course for a sec. We are fixing the problem but should I be concerned with any damage because of these drops? What would a drop in pressure do to the pistons , rings etc.?
Old 07-25-2008, 05:46 PM
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I know that at around 30PSI I pegged my wideband gauge at 18:1 AFR..Not good!
Old 07-26-2008, 12:09 AM
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As long as you weren't going WOT when it happened, and just cruising around lightly, you'd probably be ok, but I would definitely NOT run it if you were having problems like that.

Pull your plugs, if the plugs looks clean, then you're in the clear. Then do a leak down test and compression test to make sure there isn't any outliers that may point to a ring problem.
Old 07-26-2008, 09:36 AM
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Thanks, thats the info I needed. At the time I wasn't WOT, in fact it was at low RPM and backing off acceleration, so I feel a little more at ease that minimal if anything was damaged.
Old 07-26-2008, 09:49 AM
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Well, like i said, pull the plugs, they tell a lot about whats going on in those chambers. If the electrode and strap are not erroded, and if the porcelain doesn't have any metalic or black speckling you're golden. If on the other hand, the electrode or strap is pitted or eaten up, then you've got damage almost guaranteed. But, if you were low rpms, I highly doubt anything is amiss.




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