badass951

While I was looking for a problematic cause for the smoke I have been getting, I forgot to relate it to my exhaust...a 3" Borla with the Cat bored out. Without the cat I am just blowing everything out the back.

Also, I looked over everything and have not found a single leak. I believe the coolant has just been releasing pressure through the overflow. Everything is fine...the coolant level is perfect and the temperature has been running perfect.

Tyler Frasca

Not to sound pesemistic, but that sound almost sounds like detonation. I know little about porsches, but lot's abuot turbo in general, and that's what it sounded like to me. please correct me if I'm wrong. Great looking car, by the way.

I hope to have one soon.

badass951

Are you referring to the sound of the turbo when I shift?

If so, it does make a weird sound, but it has been checked out by Porsche since I bought it only 3,000 miles ago. At the time when I bought and when it was inspected it made this sound. There is a different wastegate on the car, but I am not sure what else might make this noise.

Mledbetter

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by badass951:
<strong>Are you referring to the sound of the turbo when I shift?

</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">I think he is talking about the sound it makes right when it spits out the white smoke. Sounds like either detonation or a slight misfire.

-Matt

badass951

I have gotten a lot of different opinions at this point...does anyone know the answer? Is it the turbo?

Mledbetter

Is the smoke white?

Does it only happen at high boost / high rpm?

What boost are you running?

Does it happen in all gears?

What do your plugs look like?

What do the tops of the pistons look like?

Does it "feel" different when it happens? Loss of power?

-Matt

Tyler Frasca

If the sound is knock, then maybe you don't have enough fuel. What does your A/F guage read at full boost (which is presumably when that noise happens)? If it reads rich, you're probably fine and it could be the turbo. If your engine is satarving for fuel, it would knock, ping, detonate or whatever else you want to call it. Bottom line: if it is knock, you need to fix it before serious bottom end damage or a hole in the piston. By the way, I am extremely envious of you and your car.

Ahmet

We can only guess w/a video of the car from a fair distance. Answering mledbetter's questions would help. Also, the noise could be the wastegate.
Ahmet

badass951

I was thinking the noise was the wastegate, but here are the answers to his questions...

Is the smoke white? - tough to tell, but it does look of lighter color

Does it only happen at high boost / high rpm? - the smoke and noise only happen at hi rpms and specificially hi boost, yes

What boost are you running? - 14 psi

Does it happen in all gears? - can't recall, but I think it has happened in a couple different gears

What do your plugs look like? - need to check

What do the tops of the pistons look like? - need to check

Does it "feel" different when it happens? Loss of power? - does not feel like a loss of power or different

badass951

I do not believe it could be a knock, because it almost always reads slightly into rich at full boost/hi rpms.

Also, if this is important, the previous owner upgraded the wastegate, but I am not sure with which one. It is mounted rightside up however, unlike on most 944s where it is mounted upside down.

Bri Bro

It is mounted rightside up however, unlike on most 944s where it is mounted upside down.

Got a picture you can post?

badass951

So far after changing the spark plugs and removing the lightbulb under the hood I have determined the following:

1. The light no longer flickers under the hood

2. I have no "metallic turkey gobbler" sound, although there was a sound that may have been it once or twice at very high boost and very high rpms (6000 rpm and beyond) - volume of sound was dramatically decreased if these were the same noises

3. Little or no smoke...tough to tell though as it was beginning to get dark

4. Flickering sound of bypass valve has been decreased in volume, although still present - sounds to be at what might be considered a normal level though

5. Car feels like it had an instant increase in power

6. Although obvious, startup is quicker and smoother

7. Engine sounds more solid at idle

I am happy with the results of simply replacing the existing spark plugs with new ones (the old ones definately did not look good, they needed to be changed without a doubt). I may not have solved my problem, but it is very possible. I will videotaped it from behind tomorrow hopefully and see if I have an improvement. From the feel of things (noticeable increase in performance) and the sounds I am hearing, everything sounds like the way it did the day I bought it.

Mledbetter

What did the plugs look like? What color and all the same color?

-Matt

badass951

NOOOOOOOOOOOOOOOOOOOOOOOOOOOOO! I think the head gasket blew today!!!!