Walter Kurtz

I've never owned a sports car and decided it was time. I loved the way the Z's look and I did a little research which told me these were great cars. Started shopping around and finally settled on a beautiful metallic black 06 GT that had 72k miles. It has a sweet lookin body kit and loud megan racing exhaust. I bought it around end of July last year.

I have to say that when I first got the car it was such a pleasure to drive and look at!

A few weeks after purchase I started to notice when I would hit it hard to get on the interstate that a lot of smoke was coming out of what I thought was the exhaust. It would happen around 5k rpm. I didnt pay much mind to it because I'm an idiot and this was the first car I really had fun driving.

I drove the car pretty hard like a dumb *** for several months and the smoke was still happening at around 5k rpm. At one point I was stopped at a light and I noticed smoke coming from the engine. I have a buddy mechanic who works at the dealership luckily and I took it in.

I had a valve cover leak and whoever owned it before me had put this aftermarket oil pan in there which was causing coolant to leak from one of the hoses because it was butting into it. My coolant was nearly empty when I brought in it to the shop. This was in December so 5 months after I bought it(yes I know Im an idiot).

So I took it back to fix the valve cover leak and after that my buddy said that when he was working on the engine he saw that coolant had leaked into the engine at some point and that the head gasket showed signs of leaking. I asked him what I needed to do to fix it.

After speaking with his manager, he was told that it wasnt even worth fixing unless I did an engine swap. I tried to get more info but my buddy recommended I sell it.

Since then I've absolutely babied the car. Not taking it over 3k rpm and I check my fluids every day. So far there has been no leaking and engine temperature has not gone high once. Im told it is just a matter of time though but no one can say for sure how long.

I'm at a loss as to what to do. I owe around 7k on the loan. What options do I have?

Is there anything I can do at this point to prolong the life of the engine?

If you have read this whole post you are awesome! Any advice greatly appreciated.

chatcher

iTrader: (3)

What was the evidence that coolant leaked into the engine? Either you have a blown head gasket or you don't there is no occasional leaky head gasket. You are most likely fine in my opinion. Unless you re getting coolant in the oil now there is no reason to think your engine is on its way out. Do you know what oil looks like when it is mixing with coolant? For sure keep an eye on things. And maybe get a second opinion on your cars health as your buddies diagnosis sounds sot of fishy to me.

SmoothZ

iTrader: (13)

Always get a second opinion. Not saying your buddy is inexperienced, but I would take it somewhere else and tell them what's going on without mentioning the previous diagnosis from your friend.

Walter Kurtz

Ok. On the 2nd opinion what would I tell them then? Since technically it is running fine right now. My mechanic buddy checked my coolant to see if there was mixing and there was none. That was weeks after I got the valve cover leak fixed. My other buddy who is the mechanic at the dealership told me I had a blown head gasket and replacing it could make it worse?

SmoothZ

iTrader: (13)

Tell them you're getting black smoke from the exhaust and that you think there may be a leak or a bad head gasket. They should look for anything that would cause that, so they'll focus on the engine.

dcains

iTrader: (15)

You can get two things done, both of which are relatively inexpensive, and they'll give you some valid information. The first would be a test for combustion gases in the coolant, and the second is a compression test.

You can buy the coolant test kit and do this yourself to save some $, but given your lack of experience, I'd pay a pro to run the compression test.

https://www.amazon.com/OEMTOOLS-2714...s=block+tester

Works about 90% of the time.

dcains

iTrader: (15)

I might add that a leaking head gasket, with coolant in the combustion chambers, usually results in white, sweet-smelling smoke from the exhaust. Black smoke indicates an over-rich condition, which could be a symptom of a bad head gasket and incomplete combustion, but that's not as definitive. Running over-rich will surely trash you cats, though, and I'm surprised you didn't mention any codes related to a check engine light. Are there any?

Walter Kurtz

There wasn't any other codes mentioned when I took it in. But I do have an 02 sensor that causes the light to stay on. I'll probably run the codes again today to be sure.

On the compression test, what am I looking for?

When the smoke was coming out a lot it was white. I forgot to add that before I got the valve cover fixed, rhe heater was not blowing hot air or only briefly when I was on the gas.

dcains

iTrader: (15)

Compression numbers should be in the range of 180-205psi, with less than 10% variation between the cylinders.

If you had white smoke, you've got a head gasket problem, and rest assured, these things don't go away or repair themselves. I'm hoping your friend didn't dump some sort of sealant in your coolant, because eventually that will cause even more problems.

MicVelo

Your car is exhibiting a multitude of problems that frankly, don't seem to correlate.

You're saying it was white smoke and coolant was low - that jibes. Coolant loss/burnoff is white as dcains said.

But in another sentence, there were leaking valve covers which, when burned or burned off exhaust, oil burns blue/black.

And now the fact about the heater failing to produce heat.... a coolant/circulatory problem.

Hmmmm.....

At this point, I would do what smoothz suggested.... take it in to another Nissan dealer or authorized Nissan tech for another full diagnostic based on symptoms AT PRESENT. Tell them a "friend said something about a head gasket but you don't understand what that means." If they can explain it to you to your satisfaction, that's a first good sign.

Then, they should suggest one to three things to start and can explain to you - in layman's terms what each test does and why - that's the next sign of trusting your tech. (OK, no disrespect intended on your "buddy the mechanic" but each question/answer you get is a better indicator that they know what they're talking about - a stark contrast to your friend's diagnosis "and that the head gasket showed signs of leaking" without once suggesting the proper diagnostic procedure.)

1) CO detection within the cooling OR oil system (indicating exhaust gas contamination)

2) Cylinder compression test - which shows how well your valve train and rings are doing their jobs vis a vis each of the cylinders - that is, looking for consistency or inconsistency between them - but....

3) For head gasket issues a Cylinder LEAK DOWN test is much more telling because the delta between fill and leak-down of the introduced pressure helps to reveal more precisely where your loss is, if any.

Honestly, unless I'm missing something here, the problem isn't present any longer if you've been able to drive it all this time without further complications other than the 02 sensor, which, if ignored will cause further problems down the line. So what's the real issue here?

dboyzalter

iTrader: (3)

Soooo you dont have coolant in your oil? But your coolant is leaking still? Or all is well? Or it only seems to leak when you drive at higher rpms?

Ive read that when one of the gaskets on the water pump fails it can lead to leaks that are difficult to diagnose properly...

I would bring it someplace else if your still having issues. I would be surprised if the head gasket was the issue at 72k miles.