stuntingshaggy

Ok so as some of you know I just completed my s5 turbo swap on an s4 block. I replaced the o2 sensor and capped off the open vac's I saw. Idle has improved from dying within 2 seconds to idling anywhere between 250-500 rpm for about 10 seconds, 15 tops. So it's trying really hard to idle. So here we go, idle adjustment STILL doesn't work. It seems to respond a little bit to turning the screw but nothing more than 500rpm +/-100rpm.

That I think I could sort out but now i'm keeping my fingers crossed for a good answer for this problem. About a day or two after I put the turbo on (it's been about 5 days since) my clutch started slipping more and more, and it never did that before, but then again I am going from an engine with a blown turbo that barely ran at 4k rpm to an almost brand new s5 turbo which runs 7psi at 2750rpm, so that alone is a big difference, but it didn't start right away, so I don't know. At first it was only on the freeway in 5th gear which is weird because theres more power going to the wheels in lower gears. Now gradually it's gotten to the point where even in first gear at full throttle its slipping away. Whats weird is that at full throttle it almost seems like it slips and then after a few minutes of driving I can go full throttle in the same gear and not slip. So it goes through weird stages of slipping and now slipping.

Now heres the potential causes. Number one, if my tranny fluid was low would my clutch slip? Secondly, if my rear seal went out could I have oil contaminating my disc? Third, when my clutch master went out I replaced both the slave and master with brand new ones, but before doing that in an attempt to alleviate the problem, I made some pretty big adjustments in my clutch free play and other clutch related adjustments. Could the free play be a factor in whether the clutch disc isn't fully contacting the plate?

Now the final question, are all these completely irrelevant and am I going to receive the news that I have to replace it? If I have to replace it, i'm going stage 2 with a lightweight flywheel if i'm going to through the trouble of taking the motor out in the first place. Sorry for the long *** post, I was hoping to get some input so hopefully I don't yank my engine up out of there for what would turn out to be some stupid 5 minute fix.

Thanks for the help gents
Steven

scrip7

iTrader: (6)

If the rear (eccentric) seal leaks, oil is most often "slung" onto the backside of the flywheel, and then onto the bellhousing, not the clutch disc. If the trans front seal leaks, it can contaminate the clutch disc. On TII trannys there is an inspection plate on the bottom front of the trans that will let you check for leaks or contamination. On s4 NA trannys, there is a rubber plug for the same purpose. On s5, there is no inspection hole, other than the vent on the pass. side of the case. Sounds like it's time to remove the tranny and find out what's wrong. If the rear eccentric seal or rear stationary gear o-ring is leaking, either can be repaired with the trans out.

As for the low idle/ dying, first check to see if the turbo inlet duct (TID) cracked and split when installing it on the turbo and AFM. They can split on the bottom and won't be seen until it's removed and inspected. See if the engine will stay running with propane from an (unlit) torch aimed at the inlet to the afm or air filter housing. If it will stay running, you likely have a vacuum leak somewhere. You can use the torch to pinpoint the leak.

NoDOHC

Replacing the O2 sensor has nothing to do with idle (you probably knew this).
The lack of response the the idle adjust screw indicates a bad fuel mixture (to me).

The most likely problem is a vacuum leak, which causes the engine to get unmetered air (causes it to not get enough fuel). If you have replaced all vacuum lines and are sure that there are no leaks there, you might want to check intercooler, intercooler piping and your BOV for vacuum leaks. The ether or carb cleaner trick works pretty well.

When my car acted like this (even after I fixed the vacuum leaks), the only solution was to follow the FSM procedure and set all the sensors and timing. I set the TPS first, then the idle adjust screw to get to 750 rpm, then the timing, and then the A/F Ratio (only if the screw has been tampered with).

I know that is it harder to adjust sensors on a turbo than on an N/A, but a piece of PVC bypassing the intercooler should do the trick for you.

As to the clutch, the freeplay adjustments make no difference (it is a hydraulic clutch). The low transmission fluid and slipping clutch indicates a front transmission seal leak to me.

I hope this helps some, I can only go on my own experience.

scrip7

iTrader: (6)

Hmmmm......sounds amazingly similar to what I just said......except that I would NEVER....EVER....recommend using highly flammable liquids such as carb cleaner to find vacuum leaks, especially on a Turbo engine. In my 32-year career as a technician, I have seen numerous scenarios where guys have done this very thing, most of then lucky, some of them not so lucky. Use a propane torch. They are cheap, last a long time and are controllable. You can even adapt it for a few bucks and put a long piece of vacuum hose on it so you can strategically aim the gas around small areas....injector seals, under the UIM, etc. Please people just stop recommending these unpredictable fluids for vac leak testing. I know people have used it for years, and lots of you will want to flame saying you've had good results, yada yada yada. Just get the torch. If you don't have one, I bet a neighbor does.

J-Rat

iTrader: (2)

No flaming here, I always get nervous when using carb cleaner to find vac leaks. I might try your idea since I have a propane torch..

Rat