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Discussion Starter #1
Compression test results are in:
1: 165
2: 155
3: 165
4: 160
5: 165
6: 160

Other than that, he said the car is running smoothly. The turbos seem to be my main issue with the car (good thing I'm getting sport 500's instead). The injectors ohmed within spec apparently, so he thinks my connectors may be corroded (to have caused cyl #3 to cut out).

Know what's funny though? He wrote on the receipt "aftermarket exhaust is a poor fit". lol... say that about a labree will you!?! He said that because the pipes were touching my exhaust crossmember, but I think that's because the rubber shoes in the hangers have slipped out causing it to hang a tad lower.

He couldn't find out what the "whirring" noise was though, he said he hasn't heard anything like it before (great). It goes away once the car is warm though, so I'm not too worried about it.

Yesterday I changed the oil, put in 2.5qts of mobil 1 10w30, 1 quart of amsoil synthetic ATF, and 3oz of seafoam. For the past 60 miles of driving like that, the car seems pretty happy.
 

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Great News!!! Your compression numbers are terrific, indicating no internal probelms. That's the Big Concern with a used engine - history unknown, isn't it?

When you wrote earlier that #3 was on and off, unpredictable, that usually always points to an electrical error or fault. When a used engine has been warehoused and maybe exposed to more moisture than being driven daily in a vehicle, I would guess all connectors should be thoroughly inspected and cleaned, or even replaced.

Was there no way to check or verify those turbos for health before the engine went into the car? It's a shame you gotta pull it back out for them.

By the way, what's wrong with 10 psi boost? What is the standard boost for the original TT? Has the oil smoking at the turbo ceased?
 

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Playing devils advocate here.. Take no offense please..

He says the exhaust is ill fitting and cannot figure out what the whirring sound is?

-Did he do a boost/vacuum leak test? I ask as I have seen boost/vacuum leaks that went away for the most part, or at least to a mostly inaudible level, when the lines had expanded after warming up.

-Fun ECU Diag?

-Did he test the injectors at the ECU or the injectors themselves?

-If he thought a connector to an injector was bad did he test to confirm?

IMHO lots of open ended questions and answers that seem suspect..
 

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Discussion Starter #4
Dave: I too think the misfire was electrical, but remember the wiring harness was used from my old motor (and I filed the terminals on the injectors)
There may have been a way to check the turbos before the motor went in, but I wasn't aware of it. I spun the wheels by hand, and they showed no play.. so at that point that was good enough for me (mistake!).

What's wrong with 10psi boost? Well, stock is 9.5, I used to run 16. Plus, this is not a smooth boost, it's rough feeling as if one turbo isn't boosting.



Kenny:
The whirring noise most definitely is not a vacuum leak (I know those quite well). It's hard to describe really, similar to blacksc's but at a higher pitch/frequency, it's odd. I'll record a video of it sometime

He actually didn't diagnose the whirring while it was in the shop, since the car was warm at that point and not making the noise. He was only able to check it with a stethoscope outside when I came to pick up the car, and requested him to listen to it.

I ran a boost leak test after installing the engine, before the initial start. No audible leaks.

I've checked the ECU several times, always 55.

Also, I believe he tested the injectors themselves (I think), he told me they were fine but an intermittent misfire would likely be the connector being corroded (which it is)
 

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Now you know why I'm such a strong advocate for installing a new harness when doing an engine replacement. It keeps you from having to trace down electrical problems like the one you've just experienced. It's $330 well spent.

About the turbos... If you're boosting to 10psi and you have no smoke, then it's unlikely that the turbos are "bad". Explain what you mean by "rough feeling". It sounds to me more like a fuel issue then a bad turbo. You may also have a CAS issue or a bad TPS. Either one has been known to cause an unstable acceleration feeling. As for the 10psi of boost, each engine will require different settings to get the boost at the same point. If the engine came from an Auto and your old engine was a manual, then the turbo's themselves are different. This will change your spool up characteristics. Are you running a boost controller or boost jets?
 

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Discussion Starter #6
I'm running a profec b boost controller right now. The TPS in the car is brand new.

I've tried turning up the boost controller to what should be a good 15psi+, and they just don't want to go past 11-ish as a max. In normal driving and light acceleration, the car is completely smooth. When I get on the throttle a little more to bring out the boost, it's as if the car holds back and then starts to boost. They feel lazy
 

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Whirring... is that the same sound from the video you posted? Or something else? Whirring at startup/cold sounds like a fanclutch. Do you remember the sound my Z was making when I stopped in(wow... 9 months ago)? That was probably quite a bit louder, but a bad fan clutch.
 
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