Normy

I drove the car all around Fort Liquordale today. Tonight, as I left Home Depot around 4 PM I noticed that the car seemed to be doing what it used to do when the MAF connector corroded. Upon initial touch of the gas pedal, the car car would bog down slightly, and then pick up when the pedal went a bit further. I was always able to correct this problem by cleaning the MAF connector. Only, before it took a period of days to slowly happen. Tonight it happened very quickly, and I wound up with the car stalling at lights. This car has never had a problem with idle speed at stop lights- but today it did, and what has me concerned is that each time I re-started the car at the lights...I got a big cloud of blue smoke from the exhaust.

I've had a small puff of blue from the exhaust for several years now; I had a mechanic at a Porsche shop run by the President of the local PCA do a compression check about 4 years ago, and the car had one cylinder with about 15% loss. This fairly experienced mechanic told me that he thought that #5 cylinder probably had a minor cylinder wall gouge, since the valve seals were holding pretty good. This 15% is within limits- barely.

Anyway, something changed today, and now the car won't idle and I'm blowing blue smoke everywhere. I didn't do anything today but drive the car at normal speeds, which means tops 6000 rpm. I can't remember anything going "pop" or any problems occuring suddenly. Really, the problem just sort of came up slowly, gently, out of nowhere.

Dammit-

Any ideas? I'm going to have a compression check done on it tomorrow.

Dammit!



N!

[It's an S2: 6000 rpm is normal~]

Randy V

Hope it's something simple to fix, Norm.

I told you that not being nice to me would have a karmic backlash...

Shark Attack

corrosion finally made its way into the MAF??

ZEUS+

Cleaning the connections could be coincedental. It could be a poor connection from having them on and off so many times. Make sure they are making good contact and not bent open. Valve seals have no bearing on a compression test.

AO

I'd run a compression test. Blue smoke is oil. Hope the outcome is good, but i fear the worst for you Normy.

Normy

snarl~

!@$%^&* dammit!

I know you are probably right, but I was hoping to take it out on some sort of large local fish. Tarpon came to mind. That, or the manatees behind my house.

N~

atb

Could be the LH brain.

SharkSkin

Starting with the cylinder that showed 15% loss before, check the plugs for oil. If you don't see any significant oil fouling it could be as simple as an exhaust valve seal. If one plug seems oil fouled then it's probably one or more rings or a really trashed intake valve seal. You can pull the intake to look for evidence of a leaky intake valve seal.

Leakdown test is more specific than a compression test -- once you've found a bad cylinder you can determine whether it's a valve or ring problem using a leakdown test.

Before you go tearing all of you hair out though, make sure you don't have some kind of breather malfunction that's dumping oil into the intake.

Normy

Ok, today I pulled all the plugs. I noticed nothing more than large amounts of black soot. If you look in the manuals, it tells you how to test the MAF. Since I'm an expert just shy of John Speake with regards to my MAF, I know how to set it with an ohmmeter. I suspected this culprit from the beginning, or more correctly it's connector, and today I pulled this item too and cleaned its contacts. They were pretty clean, but I cleaned them anyway and then set the MAF to 300 ohms, which is actually fairly lean. Zero is totally lean, and 1000 ohms is the maximum. This is idle mixture, but then again my problem was most notable at idle the other day anyway.

After cleaning the plugs, I started the engine and it ran perfectly. I drove it around town for 30 minutes today, and it performed perfect. I have no idea why it gave me trouble yesterday, since this car has a sophisticated LH-Jetronic injection system. The plugs tell me that the car isn't being driven enough, and the carbon is building up from all my crawling through neighborhoods, which is a perfect description of my late driving with this car. My dad would probably tell me to take it out on the highway and blow the carbon out of the engine, just like he did when he was a kid. The problem is that the 1950's- 70's vehicles that he's most knowledgeable of were scary at 90 mph, and barely controllable at 110, if they could even get there. My 928 cruises at 110 mph at about 33% throttle, and that 110 mph will soundly put you in jail if the Florida Highway Patrol has one of their Cessna 182's aloft or you decide to pull over when the brown and tan Crown Vic flashes blue and red lights behind your ***.

The long and short- I don't know what the f*ck is going on with this car right now. There was NO blue smoke at all tonight. I'm starting to wonder if I'm driving Christine....



Thanx for your help-

N

WICruiser

I suspect that you indeed had a connection problem at the MAF and the combination of taking it apart and cleaning provided a fix, at least for the moment. The good news is that it appears your plugs were all similar so I don't think you have any internal issues to worry about.

the flyin' scotsman

A compression problem doesn't go away by itself so one would assume whatever is the issue is intermitent with another device.

You mention the MAF connector; is the MAF new?

What about the LH?

Garth S

If you are running blue smoke and have 'sooty' plugs .... that has apparently cured itself - it is possible that via your breather systen, the motor has chug-a-lugged a snootfull of oil: have you topped up oil recently? - looked behind the MAF for accumulation?, etc.

SwayBar

It appears that N! may have solved his problem (..fingers crossed), but this is a well thought-out post for anyone to use in the future:

By the way N!, what happened to Spridle? That was a cool avatar!

AO

Happy days for you, N! I feared the worst, but looks like maybe a few Leprechauns decided to have a bender in your car!

SharkSkin

Normy, you're not going to blow much carbon out cruising at 110. What you need to do is run it through the gears, WOT & redline. Freeway on-ramps are good for this, especially if you can begin accelerating from 1st because you can get two trips to redline without much risk of a ticket.

If you're blowing out carbon you will see a puff of brown smoke(know your color codes! ). Repeat until you don't get that puff of brown smoke & you're done.