1988 928S4 running rich

Hi all! I am new to this club. I just bought my 928 S4 last spring. I had a small leak in the head gasket that was repaired. It has 944 injectors on it and a Vortec supercharger that was on it already when I purchased it. It is running very rich, which is probably why initially it was not as much of a problem since the leak probably helped. Once the leak was fixed it became more of a problem. Any ideas?

Do you have any records of what maintenance was done prior to the supercharger being added? Has the MAF or LH ECU ever been rebuilt? Intake refresh? Was the Sharktuner used during tuning?

Any 928 with boost added needs to be VERY carefully tuned! If/when that is done they can run extremely well and be quite a joy to drive and last for a long time. The key is in the tuning though (assuming the person doing the install was competent to at least get it all plumbed correctly) and it needs to be done carefully and well. Preferably by someone who has done it before! Good luck and keep us posted!

Austin, I do have quite a few records but none that show what was done that you asked about. Unfortunately, I do not have any records on the supercharger itself, which makes it a further challenge. This being my first Porsche and my first supercharger makes it quite interesting.

You can rent a Sharktuner through 928sRus, though I would recommend finding a mechanic near you who is familiar with using the Sharktuner and has experience with it already. That may be a lot easier said than done as I am not aware of anyone in your area with any knowledge of the Sharktuner or how it works.

Trouble, what makes you think your car is running rich?

-We can help you figure out what is going on when you tell us ALL of the symptoms. I have an air/fuel ratio meter that I installed myself in my glove compartment. I imagine your car has one somewhere as well. It is entirely possible that your car has a different problem, we don't know what advice to give until you tell us more.

As to the supercharger kit, if you can post a picture then it is quite likely that someone who is a member of this group built the thing!


N!