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Discussion Starter · #21 ·
Well I finally got to working on the car again and started pulling the intake apart and found some oil and what looks to be metal in the intake piping is this enough to be concerned about?

 

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Discussion Starter · #22 ·
well I finally got it running after 6 years of sitting and there is a pretty bad knock but it seems to be coming from the top end on the rear head with a single cylinder misfire is it possible that I have a collapsed lifter or sticky valves? Tell me if I'm wrong here but if it did bend valves wouldn't it have bent all of them not just 2-4 on one cylinder?
 

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well I finally got it running after 6 years of sitting and there is a pretty bad knock but it seems to be coming from the top end on the rear head with a single cylinder misfire is it possible that I have a collapsed lifter or sticky valves? Tell me if I'm wrong here but if it did bend valves wouldn't it have bent all of them not just 2-4 on one cylinder?
Not saying it's the case here, but we've heard that story many times throughout the years... The cause being one of the intake manifold end stud lock washers dropped down the intake.
 

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93 NA ATX 3000gt DOHC
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well I finally got it running after 6 years of sitting and there is a pretty bad knock but it seems to be coming from the top end on the rear head with a single cylinder misfire is it possible that I have a collapsed lifter or sticky valves? Tell me if I'm wrong here but if it did bend valves wouldn't it have bent all of them not just 2-4 on one cylinder?
Not saying it's the case here, but we've heard that story many times throughout the years... The cause being one of the intake manifold end stud lock washers dropped down the intake.
Yes you’re more than likely to bend all the intake or exhaust valves on a bank of pistons if timing has jumped not just one cylinder, more like 2 valves on each cylinder of a bank.

RealMcCoy’s post above seems most likely to me also. If you pull plenum and remove plugs, if RealMcCoy’s guess is correct you’ll probably find a spark plug with end chewed up. You could also then use bore scope to look for damage and/or do compression check or leak test to determine the severity of the damage.
 

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Discussion Starter · #25 ·
Thank you for the reply I'll be sure to check for that because I don't really trust what the previous owner said he swore it had a bad head gasket and it does not it had a good bit of oil in the lower portions of the charge pipe so for all I know it was making this noise when parked
 

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Discussion Starter · #26 · (Edited)
IGNORE THE NUMBERS wasn't paying attention and used my old gauge will update when I do a test with my know accurate tester

about taking so long to return to this discussion had family stuff come up. So I finally got back to working on the car and did a compression test here are the results will try to dig into it more next week
2-85. 1-110
4-87. 3-105
6-118. 5-109
 

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93 NA ATX 3000gt DOHC
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Old compression tester is only 9 psi off so It looks like I'm probably due for a rebuild what do yall think
Not sure what the first numbers are, but the last number on each rear cylinder is below lower limit of 115 psi on the turbo engines at coolant temperature of 176-203°F. Not knowing what engine temperature was and which way you tester is off, those numbers maybe within minimal limits but I’d expect the engine to still start at those compressions, maybe just not run at best performance. Also I don’t understand why you didn’t test front cylinders, jumped timing belt would affect front back also.

Did you rent a bore scope to look around in each cylinder for something in cylinders as @RealMcCoy mentioned back in April, or visual evidence of valve contact in top of pistons as I was referring to back in April about damage?
 

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Discussion Starter · #29 ·
Not sure what the first numbers are, but the last number on each rear cylinder is below lower limit of 115 psi on the turbo engines at coolant temperature of 176-203°F. Not knowing what engine temperature was and which way you tester is off, those numbers maybe within minimal limits but I’d expect the engine to still start at those compressions, maybe just not run at best performance. Also I don’t understand why you didn’t test front cylinders, jumped timing belt would affect front back also.

Did you rent a bore scope to look around in each cylinder for something in cylinders as @RealMcCoy mentioned back in April, or visual evidence of valve contact in top of pistons as I was referring to back in April about damage?
All numbers are compression numbers 1-6. The gauge read 9psi lower then actual pressure. engine was probably about 90f so it was cold drained the old gas out of it and haven't put any new gas back in to run it. pretty sure I'm just going to get some cash together and do a complete rebuild on it at this point. Any recommendations on where to get parts through I know of a few but haven't used any of them before. I've heard good thing about 3sx but there prices seem high compared to others
 

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All numbers are compression numbers 1-6.
Ok…. Now I understand, I thought top row was cylinder 2 with a reading of 85.1 – 110 :oops:

So yes you need at least a valve job, because even considering tester error and cool engine, the cylinder 2 reading of 85 and cylinder 4 reading of 87 couldn’t even come close to the minimum pressure.
 

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Discussion Starter · #31 ·
Sorry about that I didn't even notice the period behind them till now. That was my thought so next time i get a chance to work on it again I intend on putting my leak down test on those cylinders and see where it's going I found a invoice from 2005 for a complete engine rebuild with the odometer only having 1200 miles more on it now then when it was taken to them based off the amount of metal shavings I found in the charge pipe I feel like the previous owner ran it for to long on a bad turbo and caused the low compression
 
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