JakeS2

Thanks dr bob. I'll check that. I don't have a mityvac but I have (11 pcs of) Irimo ZH405 vacuum pumps. Maybe I can use one for testing

JakeS2

While waiting for other parts to arrive I decided I'll do additinoal tests with vacuum leaks. And guess what, found some. The oil breather pipes that run from pass. side valve cover to intake leaked! Not much but just enough I suppose.

JakeS2

Ok, this is closing post for this oooold thread.

Running rich original problem: injectors were totally shot! All 8 of them leaked(!) and two leaked really bad. All of them were clogged also and two of them were really clogged.

So, what happened? We pulled intake for ICV change and managed to get some sand into the engine (yes, proper cleaning next time) - so, engine apart.

Engine out and took heads off - and then I took a long breath. Head gasket on both sides had failed on two cylinders (yes, matching to the clogged ones) and if we would have continued to run on that year - engine would have gone boom!

So, little summary...
- cylinders were ok, no scratches
- new rod bearings
- all new seals
- machined heads
- valves where worked to match factory values
- S3 cams
- new ICV
- new this and that
- new coils

All by myself! I have never ever re-built an engine from scratch on my own, so the Porsche 32V V8 is the correct setup for the first time - after this nothing feels like a 'big job'.

...and now getting a techedge + LSU4.9 to monitor running.

M. Requin

Thanks for the history, the details, and the great followup- great job!

JakeS2

Let's put closure to this thread.

So, although the engine was rebuilt, it did not fix the strange running rich problem. So, back to debugging table:
- o2 sensor : changed, no effect
- another coil changed (as it was almost dead!) - some improvement but immediately when engine got warm - it went rich (AFR +10).
- re-re-re-re-recheck regulators and dampers - BINGO! When engine was just shut down, taking vacuum line from regulator caused a fuel leak. Decided to change 'em all.

So, we're now at 14.7 idle AFR, on WOT it goes to 12-ish (we have maps from 0 to rev.max on 4. gear), on normal acceleration it's at 13-14.

Thanks all guys who helped on this thread, really appreciate.

--Jarko

ps: For all the 'what the F I am doing' and 'is this really worth this' thoughts are immediately set to null when you have 40-50km/h on the clock, third gear in and slam the pedal to the metal -- and upshift. The push, the grip and the noise. Love it.