Hello all. I'm new to these forums and a new 1991 300ZX owner. I recently bought my Z from a private owner and have a few problems with it. First off, It's a Twin Turbo with 180K miles. I have most (if not all) the receipts for work done on the car. The car has a Greddy Boost Controller and a new computer that was installed for "Greddy Compatibility". It also has upgraded side intercoolers, an upgraded intake, and apparently, upgraded injectors. After taking ownership of the vehicle I noticed the car has a small power steering fluid leak, a hissing sound in the cabin that seems to be coming from the clutch booster, and a bad idle. Not to the point it would stall however. It sounded pretty bad when it idled though and idled low. I found one of the injectors unplugged so I plugged it in and it sounds tons better but now, while idling, it occasionally drops RPM from 800 down to 500 and then bounces back up after a while. It sounds and feels like it wants to fall on it's head. Any insight? Second, When the Greddy Boost Controller is enabled, I get a maximum of 7psi boost. With it disabled (off) I have achieved a peak boost of 22psi. I want to figure out why there is such a crazy difference. I have tried reconfiguring the boost controller with no success. If any one has experience with these controllers, could you please post your config and what psi you achieve? I'm sure I had a third question but I can't think of it right now. Anyway, Hello, and thank you for having me in the forum. I look forward to getting to know you all.

 

Sell the car, go buy a 350z and never log onto these boards again......

 

Wow, classic and flame-tastic. Perfect response coming from a simple mind.

 

Fixing the vacuum leak to the clutch booster should help the idle.

 

UPDATE: Found the previous owner disconnected the knock sensor... ??? Reconnected it and idle is low but stable at a low setting. The only thing left to fix is the hiss coming from the clutch booster area. I've tried disconnecting and plugging the hoses but no change at all. I'm wondering if the sound is "transmitting" through the hole in the firewall from somewhere else. All I can see there are a small vacuum hose and the clutch booster. Any insight as far as any other nearby vacuum hoses or such?

 

All fixed. Found the prob.. Everything is working great and puuuurrrss like a lion.

 

What was the problem???

 

LMAO my z smokes 350s all day and it has a crap load of probe from the previous owner, plus IMO it looks better, and is faster for 1/2 the price... In my case. Not bashing but don't come up in the 300's territory talking smack when it dominates the 350.... Biioootch!

 

You completely missed the point of my post.