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Discussion Starter #1
Name: Nar (nickname)
Location: Antioch, CA, U.S.A.
Age: 32
Occupancy: Student (Auto Technology Major)
Schools: Los Medanos College, also Butte College

Hobbies: Driving, Wrenching, Racing, Design, Fabrication, Reading, Writing, Roadtrips

How'd you find the forum?: Google search

Pic of me:



About Me:

Hello all, my friends call me Nar. I just got my first Corrado (a 93 VR6, look in my garage for more info and pics), and I was hoping to learn more about them on this forum. I actually traded my most recent Mazda RX7 project for it. I've mostly owned japanese cars up till now (and one BMW), but my first car at the age of 18 was actually an 81 Scirroco 'S'.

I was a mechanic for several years, but now I am back in school at Los Medanos College to get a degree in automotive technology. I want to start a custom fabrication business.

My love for driving started on the backroads, and then progressed into auto-x and rally-x racing. For a little while I was a high performance driving instructor at Thunderhill, as well as a drifting coach. I was also pit crew for the Butte College Raceteam on a few of their racecars.

What I want to learn:

So this corrado of mine has a lot of miles on it, Over 199k, and I'm worried that it may need a rebuild. I started it this morning cold, for the first time since I bought it, and I noticed there was a mixture of oil and water being sprayed out of the tailpipe.

It doesn't want to overheat, but it seems sluggish and doggish at low revs, and it wants to backfire a lot.

Any tips or ideas would be appreciated! Meanwhile, I'm going to start searching and trying to find a link to the FSM.
 

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Discussion Starter #2
Nars Corrado VR6

Ok so first of all I decided to do a pre-test at my school today.(Smog technician training is one of my auto courses). This is the results of today's pretests on top of the results from last year. (Which is the only prior smog record I have.)



After that I thought it'd be a good idea to do some maintenance, so I removed the distributor for inspection. I realized the rotor wasn't solidy affixed to its shaft. It was just wobbling on it, which concerned me cause that could cause weird spark timing. I checked the manual and it said you're supposed to glue it unto the shaft, so I did that. I also noticed the hall-effect sensor was covered in grime, so I cleaned that as well before I reinstalled it.



Then I started pulling spark plugs. (These were Denso's.) Three of them were badly badly gunked up, so I replaced the whole set with some new Bosch plugs.



After I changed the oil I went for a test drive. The car starts easier and idles smoothly now. But it still feels a little sluggish and unresponsive at cruising speeds under slight throttle. Wide-open-throttle however is another story. It really comes alive and zips through the rev's with no hesitation whatsoever.
 

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Discussion Starter #3
GIAC chip?

What about this GIAC performance chip that's supposedly in my car? What's the story on those? Is it something that could be causing some of the drive-ability issues?...namely running too rich or screwing with the timing? Is it removable?
 

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MK4 & MK5 Owner
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Older cars like yours usually have soldered in chips. Not removable. But you could always just find another ecu and swap them out.
 

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Discussion Starter #5
Diagnosing Misfire

So today was a rather productive day for the Corrado. I did an alignment on it. Can anyone tell me what good aftermarket alignment kits are for the rear end? Since it's non-adjustable from the factory back there...

But it started to misfire really bad today, like obviously only running on 5 cylinders. So I brought it back home and started diagnosing things...



First thing I realized is that after I changed the plugs the other day I forgot to plug the hall-effect back in on the distributor! :rolleyes: I also diagnosed that it was cylinder #6 that wasn't sparking and pulled all the new Bosch plugs back out. Cylinder 6 was totally fouled again. But after searching about it, apparently these cars don't like the Bosch plugs they foul too easy. I read the NGK copper's are more reliable so I'll swap a set of those in tomorrow. But there's no doubt this engine leaks a bit of oil into cylinder #6. I should start thinking about a swap or a rebuild... :-?

I also changed the engine-speed sensor down on the block cause the wiring looked pretty old and cracked on it. I wanted to swap the 02 sensor also... just because it's the only other sensor I have spares for... but it's mounted at a pretty awkward angle on the exhaust mid-pipe before the cat. There's no easy way to get it out without removing the mid-pipe from the down-pipe. I'll wait on the 02 sensor until I'm ready to do new exhaust gaskets, cause I think I have a leak at the manifold, but I couldn't see any cracks thank god.

Last thing I diagnosed was that the K&N air filter the PO installed fits like garbage. Gonna put in a regular air filter that seals properly tomorrow as well.
 

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Discussion Starter #6
Misfire Fixed

Ok so after installing NGK plugs, a new WIX air filter (and the other stuff I mentioned in the previous post) driveability has much improved. The misfire is gone and there isn't any of that partial-throttle sluggishness I complained about before.

Still feels like there's room for improvement though, but given the internal oil leaks and smoke at wide-open-throttle any other fixes would be band-aids at this point.

Also, I can feel the clutch slipping a bit so I might as well rebuild the motor if I'm gonna put in another clutch.
 

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Discussion Starter #7
Failed Smog

So unfortunately even though the tailpipe emissions are fine... the Corrado failed smog today because there's too much 'visible smoke' during the snap-test (quickly revving from idle to 3k). There's no way to fix that without rebuilding the engine.
 

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Discussion Starter #8
In other news, I finally got a chance to do a complete brake inspection today. The front rotors and pads are badly scoured and basically junk. The rear rotors are even worse. They are cracked in four or five places like pizza slices.

I already ordered some new Powerstop drilled/slotted rotors... and I am gonna browse for pads and fluid. I need to research what brands are really decent for german cars?
 
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