eddieviv

Folks,

Wondered if you could help out...In the morning when I first start the car I have a lot of what looks like water and large droplets of black soot coming out of the exhaust. (spraying on the garage dooor). I can also see them on the rear bumper. Mechanic said car was really running rich and has adjusted but the car is still doing it...as well upon heavy acceleration with the turbo workin' it's blowin' huge "puffs" of black smoke but only when I accelerate hard.

I too also have a problem with exhaust fumes in the cabin. I've read a lot of posts on it and discovered a lot of folks have the same frustration. I've changed door, sunroof, rear hatch seals and it's still drifting in especially with the windows down. If the car is "sealed up" no fumes, and I can run the fan with fresh air. If I run A/C though, it's really bad. Help!

Ski

I would guess that you have a serious boost leak in the engine compartment, ie intercooler hoses, throttle body, or you have some vac leaks from cracked/dry rotted items. If you're still on the original hoses, time to change just for maintenance IMHO. If you want original type hoses and vac line/rubbers, www.944online.com, vac line kit updated silicone, www.lindseyracing.com

Now the A/C deal, may be a cracked hose on the IAS, idle air stabilizer, or aluminum pc at the intake could be loose. What year is the car, where do you live? This is a great site and well worth the membership. Welcome to the board.

Oddjob

Nothing with the AC should cause more exhaust to enter the cabin, than just running the vent/fan (?), thats odd.

Check the rubber seal on the firewall - it seals against the hood and keeps the blower motor fan from pulling air into the car from the engine bay (can get some exhaust smell in the cabin if that seal is missing or falling apart.

But if its more pronounced with the windows down, my guess is that its just one more symptom of the car running excessively rich - get that problem solved and the smell will probably go away.

Does the car have the cat removed? That is one reason that you will get the black spit out the tail pipe on startup. But it should not be smoking black when driving. Has the car seemed down on power? Does it have a hunting or high idle (above 1000 rpm). What chips are you using? Also check the fuel pressure, a failing FPR may be running excess fuel pressure (although this is unlikely).

eddieviv

Thanks to both of you...I'll check the rubber seal on the firewall. The FPR was just changed out at $186.00. And yes the Catalytic Converter has been removed. Does this mean I'll always have the spitting problem or do you think the car is still running too rich? Y'think if I fix the running rich problem the black smoke problem will resolve itself? Idle is smooth as silk @900 steady. It was chipped by the previous owner 8 years ago so don't have the details.

A lot of these problems started when I installed an autothority mass airflow system...Could this be a culprit causing some of my issues? Thanks again, this forum has really provided a lot of information that I wasn't able to get before so thanks to all!

eddieviv

Oh it's a 1986 Turbo...I live in Toronto, Canada. Thanks!

Ski

uh...when you installed the MAF system did it come with a new set of chips?

95Juan

yeah, my car runs ludicrously rich. i also get some gas and soot at startup on the garage door, driveway, etc.


this is cuz of the guru chips which apparently run stupidly rich.

time to get vitesse........

hosrom_951

Pull the vaccum hose on the fuel pressure regulator and see if it holds vaccumm.

eddieviv

"uh...when you installed the MAF system did it come with a new set of chips?:

Don't know...But the car ran fine for awhile. I had a local Porsche shop install it. The MAF seemed to add a lot of horsepower. There was a noticeable difference. Today a new symptom, when I accelerate I can hear something in the MAF "fluttering"?? aaaaarrrgggjhh This car is going to be the death of me.

I talked to a Porschephile today and he asked when was the last time I had the gas tank cleaned out completely (it's plastic apparently). I've never done it and I've had the car for 8 years. He highly recommended taking it off and cleaning it out thoroughly. He claimed I could be picking up junk that's 20 years old especially when I get it dangerously low to reserve?? Ok, this sounded a little far fetched?

UK952

The mess on the garage is water (condensation) from the exhaust mixing with the soot in there, it will always happen with cooler nights. A boost/vacuum leak will make the car run rich and ytou will see black smoke, our cars are prone to leaks due to the number of rubber pipes and their age.
Stuff in the gas tank especially if you run it low always seems a little off to me, isn't the pick up in the bottom of the tank anyway? If the tank outlet (or filter) was blocked you would have less fuel and run lean.
Get a boost tester and run some checks,
Tony

Oddjob

Far fetched. Sure, there will be some crap in there, but thats what the fuel filter is for - just change the filter. There is also a little strainer in the bottom of the tank (outlet to the fuel pump) that can be removed and cleaned. I pulled the strainer on one of my cars (which is an 87T w/ 160k miles) and it was perfectly clean/clear - no debris caught up in it.

The black spit coming out of the tail pipe on startup will always exist. The carbon and moisture (water is a by-product of combustion) get caught up and burned up in the cat, but since the cat is removed, it will blow the water/carbon mix out the tail pipe. Once the car is warmed up and the exhaust system is hot, the water evaporates and exits the tail pipe as steam - so you only get the black spit on cold starts. I have little splatter marks all over on my garage door and floor from where my cars spit when started.

If your car smokes black while driving and under full throttle, it is running too rich and needs to either be tuned (car is setup or chips are mapped too rich), or figure out if there is a fault or component failure that is causing the problem (various ideas are mentioned above).

Stiletto

I had this problem when my car was stock. Blew black smoke and other wet particles out especially when boosting.

It was the vacuum lines. You have to go inspect each and every one of them for leaks and cracks. Once my vaccuum was all sealed up the car ran great.

kjagrant

I'm having the same exact symptoms with my '87 951 and I also have the AutoThority MAF kit. Based on my experience your problems are definitely related to it. Does the flutter sound happen when your on the boost and then lift off the trottle to shift. Thats when I hear it.

eddieviv

Thanks to all for your ideas..Sounds like that at the very least I have problems with "vacuum" and that I'll need to check all lines for cracking and wear...Curious about the comment on the FPR..to remove the hose and check for vacuum. Ok this may be a dumb question, but how do I do that and what's it supposed to feel like if anything - (no rude comments please.) I'm comforted at least to know that these are all appearing like relatively inexpensive fixes. I am still having a real problem with the engine running too rich but I'm hoping if I check all the lines for proper vacuum and I get the engine properly tuned some of these issues will be fixed. Curious as well about the "chips" that came with the MAF. Would these of replaced the "other" chips the previous owner put in and perhaps this is contributing largely to the overall problem of a rich running engine and black smoke? To "kjagrant" yes, that's exactly when I hear it. Do you know what's causing it? I don't seem to have any loss of boost at all (except when I really hit the gas and I get the black smoke out the exhaust and it feels like it's missing or somethin'. (It's a real love hate relationship with this car...)

special tool

both of the above problems are from ruptured bypass valve diaphragms.