Left Tail Pipe Smoking
 

I had my oil changed two weeds ago and have only driven it a few miles since. I just started it up and the left tail pipe was smoking a lot. Got a little better as the car warmed up but I shut it off after 5 minutes. Any ideas? Thank you.

Oil overfilled? OE Porsche brand oil filters? What oil and viscosity?

15/50 Mobile One.

Oil is probably overfilled. Or wrong filters. Or over torqued. Or a combination. Read the "sticky" up top.

Thanks...does any of the above cause much damage if caught quickly?

Is there any significance to it smoking on the left side? Just curious. My car smoked from the left side (at times badly) when I had the wrong oil in it and possible overfill.

Shouldn't with the proper correction in a timely manner. And proper cleanup.

Well, as you know the exhaust chris crosses.

This was covered once, but I don't recall the specifics. Something about one side being inheritley lower.

Overfill seems likeliest, but could be a leaky valve cover gasket too.

I'm guessing Mahle oil filter. They will almost always cause this issue, and Mahle still claims they work for the 993TT. Its really hard to convince independents that ONLY a Porsche brand oil filter works.

jcoles,
Your car looks really nice. I can see Ruf bumpers and aftermarket wheels. What color is it? What else is done to your car? I'm sorry to take this off your topic, but I'm curious.

Not bad. Next time elect Mobil V-Twin 20W50.

I had 2 smoking problems.

First one was from passenger side (LHD) tailpipe. Mahle filter was the culprit.

Second time was due to overfill I believe. Driver side tailpipe.

I posted freak out threads at the times of the incidents you can refer to.

In the first instance, the intercooler was removed and all the oil in it and the plumbing was cleaned up as good as possible. Replaced filters with OEM, reassembled and after several drives any remaining oil was burned off and no more smoking.

Second instance was a little more invasive partially because the smoking persisted after some corrective action and based on research on here and other advice I thought I had a bad turbo.

In addition I was doing valve cover gaskets, plugs, wires, and a bunch of other stuff so alot more got taken apart. Thoroughly cleaned intercooler, hoses, intake manifold, turbo plumbing etc.

Smoking persisted but the smoke only began emanating from the tailpipe after the engine was running for a few mins or right after boosting.

Determined that it was the muffler which had gotten oil soaked from the overfill incident and every time it got hot the oil would burn and smoke.

Replaced muffler and now smoke free.

I had a thread here not long ago about this issue as well. I changed from 10w-60 to V Twin 20w-50 using OEM oil filters (Porsche) and recently rebuilded turbos. I didn't know if the smoking was caused by bad rebuild of the turbo (was smoking left tail pipe which is passenger or RH turbo side) and later I found the driver or LH turbocharger the INLET was full of oil but exhaust was dry. Lucky enough my IC was dry almost (didn't get the oil in the IC/intake of the engine).

Culrpit at the end, was the overfill. I think I had like 1/4 of oil extra but now is perfect and no more oil/smoke.

For the CAT bit covered of oil I cleaned it and the muffler took more time to cure since it has some fiberglass inside I believe. Now all is dry and perfect.

Glad you asked because I was wondering the same. Looks like Slate to me. Beautiful.

Thanks bbs99tt. It is slate with black interior. The bumpers are Ruf along with a steering wheel, shift knob and pedals. Engine is stock. I was told the rocker panels are Ruf but not positive about that.

I'm taking my car back to my mechanic tomorrow. I hope it's just overfill

especially in Los Angeles... the v-twin 20/50 is perfect for you; your you could run it all year w/o a second thought. Plus it has the best cocktail of additives/more than government regulations allow i believe b/c its for bikes not cars.

Although on the other side of the coin it's been discussed here that catalytic converters don't like mobil v-twin one of these additives "apparently" can corrode them.... but I'm not worried the benefits to the engine outweigh the risks..... maybe if i were to put over 50k on it, maybe then.

WINNER!!!!!!! Some additional pics when you have time would be greatly appreciated. Also, since I guessed the color right I get first dibs if you ever decide to sell.

Don't mean to keep hijacking your thread but do you know if your rocker panels are just installed "over" the stock ones?

I just picked up the car. Oil level was too high. Thanks everyone for your input.

No worries bbs993tt. I'm not sure but they do look like they are. I would prefer them to be off. What do you think?

Slate is the best color after-all. ;-). I think you and I are the only 2 Slate cars on this forum...also funny we're both in SoCal as well.

Glad to hear the issue was a simple overflow.

Another mechanic, another overfill. I've had no problems with smoking in 2 years or so? Got some work done with a new mechanic convenient to my location. Switched from my 20w-50 V-Twin to 15-50 because that's all they had. He wanted to put in 10w-40 but anyway I am digressing.

How should I read this oil dip stick? It is so difficult to read. Do you start from the very bottom to the top of the twist?

https://cimg0.ibsrv.net/gimg/rennlis...bf70c630fe.jpg


993Turbo Oil Indicator

Switching to 15w-50 shouldn't make it smoke should it? Again, majority of smoke was Left side only when cold. Car was doing great until I brought it to a new mech :banghead:

Did he use Porsche OE oil filters? Proper torques?

It's hard to tell form your picture, but, oil level appears OK.

We have seen on the 993 Forum that Mobil has recently and significantly changed 15W50. And not for the better. In fact, Steve Weiner will NO longer use nor recommend.

Go back to the V-Twin ASAP.

The level should be between the lower beginning of the twist and the middle of the twist. Never above half way. 15W50 if your winter temps are pretty low. Otherwise get the V-twin back in there. Don't let any mechanic tell you what to put in your car, if it goes against what you know should be in it!
Also: I used a small jeweler file and made a couple of reference marks in the twist. Hope this helps. Take care

Thanks guys. YES I had just read the reformulation thread too but really 15w-50 viscosity should be fine and the formulation should not make it smoke should it? Mid- 50's are the highs right now in San Francisco.

Mechanic claims and on the invoice indicates Porsche filters (I INSISTED). Even Steve Weiner indicates Mahl are okay (if not better perhaps) than Porsche filters for non-Turbo 993's.

All the more frustrating because my car lives in a small condo garage. While hot I removed 700mls of oil. Letting the car cool back down and will try again. With the holidays it will be awhile before I can put the v-twin back in.

Thanks again. Merry Christmas

UPDATE - Almost 6 hours later started with smoke out of the Left pipe again!

I would guess the mechanic put whatever oil and filter he had around for your car then made out the invoice to what you wanted to see.

How would you know the difference unless you saw the empty part boxes and oil containers proving otherwise? That is why I do the oil changes myself.

I'm will do an oil analysis and it will be easy to see if it's not 15w-50. I'm up against a smog deadline too. It's smog clean when it's warm/hot - no mods. I took it to a respected place in SF but I had to return for some other issues they didn't do right. RMG and FD Motorsports are the best but not this place.

Planned on a Christmas drive today but didn't want to smoke my neighbors out. Things could be worse. Merry Christmas.

For what it is worth, after I had established that ours was no longer smoking from any part of the engine (bad turbo in our case), the oil soaked muffler and cat eventually cleared themselves. (Fortunately, in my case, I was able to establish this concretely by popping the cat off.) Once you have established that you have the right oil level and correct filters, it may just need the oil burned out of the exhaust.

^^^^^^^^^^^ and this should entail loads of fun, to make short work of it.

Ok now where was I? Ah, Sunnyvale. The oil level finally did look correct. It still smoked on start up. Tested the oil and it WAS in fact 15w-50 per Blackstone. Put 20w-50 V-Twin in and it stopped smoking. Right turbo showed some leakage but RMG said it didn't warrant replacement. I should probably install the check valves next year. Passed smog in the the nick of time. It took 3-4 drives to get all the smog equipment cleared (readiness codes). As usual the smog tester thinks it's two wheel drive and wants to put the car on the dyno then looks at the intercooler and is completely baffled. Back to normal.:to_order:

A nice Andial twin plug from Florida at the shop!

Left Tail Pipe Smoking
 

I torqued my oem filters to my "hand torque capability"...the oil in the turbo intake tract was reduced a lot, but still with some time w/o starting the engine 1.5/2 months (of inactivity) it still drip oil in the compressor side of the turbos, not the exhaust anymore (thank god)....also I had at some point overfilled of oil and that also cause this problem but is worse to have the engine overfilled of oil rather than over torqued the oem filters in my experiencie, so watch out the oul level carefully specially at hot levels where it does expand.

I just installed my TurboKraft oil feed lines...I will report later how it tuned out, if fixed this issue, partially or not at all. Otherwise I will put custom return lines with check valves to the scavenage pump.

Here are some pics. Also, you can see some thin coat of oil bath in the intake tube for the turbo.


https://cimg1.ibsrv.net/gimg/rennlis...0d7fe8c77d.jpg


https://cimg7.ibsrv.net/gimg/rennlis...89787d9eb8.jpg

Diego, the return lines won't need any check valves. Just have to have an "anti-siphon" trap in them. Either the hard (RUF type) lines with an upside down trap in them, or the flexible/braided lines with loops in them.

I left out perhaps the most important part. We also replaced the small oil filter despite being brand new. Making sure it was not the problem.

Yes, I have seen some modded or custom return lines with the loop you mention, should be enough, but some add a check valve there. If my check valve at the oil feed of the turbo doesn't work, I will go this "loop" route and see what happens.

Thanks for the suggestion :thumbsup:

Not sure if the complete system, is a constant loop on oil pressure. I think the return lines are more gravity/residual pressure, fed. Who makes the return lines with check valves?
Aloha
Richard

UMW. Ultimate Motor Works. Rennlister Kevin is the owner. Good guy.

The "return" lines.

Yeah. Pretty sure. Did you check his web site?

Left Tail Pipe Smoking
 

Turbokraft makes it. I believe Kevin does offer it too?

Kevin makes the return lines as well as the check valve lines.

What I was getting at, is the return lines (usually) don't have any check valves, just an inverted "P" trap.

I bought the oil return lines from RUF de.
Perfect product < 200.$

That's my Andial car. Is the motor still out?

^ hey Stephen haven't seen you post for a bit - not sure which is your car?

Hey Basal. Still kicking around :). Confusion is what I get for posting a reply before finishing reading a thread. Responding to Pi's post midway through where he saw my car in Sunnyvale. Back to the original programming ...

Speaking of smoking exhaust and RMG, Bob made up a set of return lines for my 97. Cured a bad smoking problem. Already had check valves installed and for some reason it still smoked -- the bent return lines fixed my issue.

^ from your sig looks like you still have a small fortune in air cooled Porsches!
(Your old motor is still running great!)

Back to topic, although I didn't talk about it on my exhaust build thread, seems I cracked/injured one of the andial bent return lines when I took the exhaust off. Didn't have any smoking, replaced it with the stock piece from my other engine. Kevin says he's out of them, waiting for his next run so I can replace it.