Airflite40

Hey gang, I am trying to fix the last nagging issue with my car.

The car runs rich, very rich. I average about 18mpg mixed city highway. I recently drove to Road America and back, and got about 350 miles and still have about 1/4 tank left according to the gauge. Thats 90% highway driving. I feel like I should be getting more. I put in a brand new O2 sensor, new fuel filter 2 months ago, and a good set of injectors from Schwank, which were cleaned and flowed by witchhunter installed last Nov.

When I was on the highway and would hit boost, my friend said he could see black smoke coming out of my exhaust.

I have recently gone through the engine, and replaced a bunch of stuff including AOS seals, and installed my Saikou Michi catch can.
Before I changed the AOS seals I used to get some milkshake in the filler tube, but since the seals were changed its bone dry. I have ran the CC for about 2 months now, and I recently checked it and there was not a drop in there.

I know the seal under the turbo is leaking, since I can see it smoking a little when the engine is hot, but that could be because I changed the all those seals around the turbo 2 months ago and could have not torqued it properly. I'm going to drop the steering rack tomorrow to see if I can tighten them down.

What else could I check? I checked/set the FQS switch yesterday, it was at 0 and I set it to 2 to see if I can lean it out a bit, but the car backfires like crazy still. Every shift I get back fire. its getting annoying.

My friend thought maybe the rings are bad, but the car only blows smoke under boost, and runs VERY strong at 17-18psi.

I read a couple of posts saying maybe the Bypass valve could be blown, but I can hear it working with my MAF pipe.

Getting a wideband gauge is next on my list, but that wont be for a few more weeks, and I have a feeling is all that is going to tell me is that I'm running rich still.


Here are some pics from this weekend......

Silver 933 belongs to John (Glen Watkins) Extra Black 951 (mine) Other Black 951 belongs to Phil (PhilR)

fbgh2o

Assuming that your gauge is perfectly accurate you got over 22 mpg, if it is pessimistic (like both of mine) it is likely over 23 mpg.

I don't know enough to comment on the rest, but just thought that I would say that does not seem as bad as you might think. Do the spark plugs reflect that you are running rich?

Mighty Shilling

In my experience, turbo cars all (including my parent's BMW's) do a small puff of black smoke on a shift or startup... I know I get a little, and my car (according to Colorado state emissions) is in perfect tune right now.

Spidey944

Been practicing your flame throwing for next year Geoff??

Airflite40

according to my buddy John, it was no small puff, more like a steady stream of black smoke when I hit boost

Mighty Shilling

Hmmmmmmm... Kurtis does that one...


Doug, naw. that 151 is brutal.

DDP

Get a wideband and a piggyback. Wheels look nice.

Techno Duck

I put about 700 miles on my Saikou Michi catch can, mostly to and from work..nothing crazy and nothing came out of my catch can either when i checked it a few days ago..seemed completley empty. I just finished a track day.. so 100miles or so of pretty much on boost the entire time. Will check it in a day or two to see if anything is in there.

Rock

Do you have autothority chips?

My car does, and does exactly everything you described AND gets roughly the same gas mileage.

My eX gf's turbo could easily rock out almost 500 to a tank. I barely got 380.

Airflite40

no autothority chips here, I have the maxHp chips burned for my MAF.

Thanks Derek! I have some Q's for u, let me formulate them and I will PM u.

black944 turbo

Your engine is probably fine. You are probably running a bit rich. I was having the exact same issues with my lindsey maf. Any car when floored should go rich. Get a wideband or strap it to the dyno. If the car runs strong, you are probably fine just need to tune it out.

Papamurphdog

Nice car. +1 on the wideband O2. Stop trying to lean it too much, it will be fine on the rich side. Clean the plugs before you track and run 100 octane race gas. You shouldn't run 18psi+ on the 93/94 pump gas for a lot of reasons, but for one the extra octane will help the charge burn better and it will make more boost and HP; it will seem like it is leaner even though there was no adjustment. If you can find higher octane, run it! As soon as I go back to 93/94 mine seems to be more pig rich than when I run a tank of 100. FYI, I get .20 extra BAR of boost with no adjustment on 100. Of course, bad advice if the car is a daily driver!!! In that case I'd still tune on the rich side to be safe under boost...

Airflite40

this is a street car right now, no track ambitions yet.

which piggyback can I use with my scivision MAF?

Airflite40

No thank you. There has been more than 1 person having problems with their maxtune, I know sharky47's and MichelleJD's crapped out.
I really try to stand by Russell, but he is either very reachable or VERY UNREACHABLE.
I will not buy something as imortant as a piggyback tuner from someone who is doing this as a hobby. next.

gordello1

I hear you on that. It's too bad that Russell's reputation has suffered badly this past year.