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Discussion Starter #1
Well, as some of you might remember I developed a severe rod knock on my way home from Thanksgiving in South Carolina. (600 mi drive)

A few weeks prior to that I started getting the knock sensor code in the ecu but no knock or engine problems.

Im about to start rebuilding but im wondering...should I replace the knock sensors and/or do the rewire job, or do you think maybe the the sensors heard the knock long before it was actually clearly audible?

Could it be they were just doing their job?

If im not mistaken the knock sensors are "listening" for detonation not so much a rod knock but I suppose the way they work either sound might trip them off.

I guess either way I should just replace them, but I guess I wanted some input anyhow because thinking back, I think maybe the engine had internal problems long before they were obvious to me.
 
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Unless you're all about getting new sensors, don't bother replacing them, just do the rewire. Even if they were just detecting the internal problems, the rewire can't hurt, and from what I researched a while back about KS problems the KS themselves rarely go awry. usually the plastic portion breaks or the plugs crack and get old. But if you wanna get new sensors, check ebay or the sale boards, save yourself alotta money.
 
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Did you notice a drop in power before the knock became audible? If the knock sensors did pick it up the ECU would retard timing causing a loss of power. If you got a KS code I would do the rewire while you got it apart....
 
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As I said, it was throwing the code for a while.

I had a check engine light since the day I got my car, and I was told by the previous owner that it needed an 02 sensor.

I didnt check the codes until right before I replaced the 02 sensor (2 months later) because the car seemed to be running fine.

When I checked the codes I had an 02 sensor code, Knock sensor code, and like 2 others. The same day, I replaced the 02 sensor and fixed the other codes, and I still had the KS code (The other codes were things related to hitting fuel cut and such that can go away just by resetting the ecu).

So at this point, Im not sure if I had a KS code since day 1 or not. It never ran any better or worse the whole time I had it until right before the knock was audible (1 hour or so) when it seemed to be really bad on power and the boost was having a lot of trouble getting even up to stock level, I should have stopped driving it then but I was 500 miles from home.

At this point im thinking the KS just need to be rewired, but none the less, It was probably retarding timing from day 1. I was told that the KS code only affects low end power or all around power under stock boost, since I had been running ~12psi all the time, the guy told me at that level of boost the ecu cant retard the timing any more so it would run fine, which is probably why I didnt notice.

2 days before I left my MBC broke (the adjustment knob blew out, so I was running stock boost for the first time ever) so I assumed any power loss or performance issues I was experiencing were because I wasnt used to running at half the boost. So, I drove the car down there with no issues.

Half way home I get the knock.

Upon pulling into the gas station I checked the oil and I was 2 quarts low. I didnt check it sooner because I did a full oil change an hour before I left and I had stable oil pressure all the time. Im thinking, since there was always a minimal amount of smoke from the exhaust at idle, I either had blow by on my rings, or my turbo seals were bad. The previous owner had less then 5000 miles on a freshly upgraded/rebuilt turbo (or so he says).

My initial inspection when I finally got the car home showed that I have excessive shaft play in the turbo and the turbine is just starting to hit the housing.

Im not sure if that is a result of running low on oil and the rod knock and shaft play happened at the same time, or if the shaft play probably means the turbo was leaking oil leading to the oil shortage and thus the rod knock.


Bottom line:

I have to rebuild my motor and get the turbo rebuilt.

Im actually excitied to do it, becuase I dont trust the previous owner at all at this point and I want to do the car over, and do it right. That way, at least, I know the level of workmanship, and the ACTUAL life of the parts.

The real kicker is, the previous owner had just had the bottom end done, because he had a rod knock, and he had just had the turbo rebuilt. I have recipts for the bottom end work. (Shop is in Florida, so no, I cant have them fix it again for free)

Im thinking maybe either the level of workmanship was poor, or maybe I got one of the rebuilt turbos that tends to go bad very fast (as I have read, several do) which caused me run very low on oil and caused the rod knock, fresh bottom end not withstanding.

I think I just bought a lemon. At least the paint is great, suspension is very nice, and now, after a lot of work, the interior is perfect.

Just gotta do this motor.
 
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If your turbo was using oil it would be coming out of the exhaust. Dont know why you lost so much oil but I bet thats the reason you got the knock.
 
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