1990 300zx problems

[grg3135]

hey guys, new to the nissan scene, just picked up a 1990 nissan 300zx over the weekend. ive been having some problems with it. rear sway bar needs to be replaced, the shifter bushings are badly worn, the parking break doesnt work, its leaking oil or some other fluid, the drivers side window motor needs to be replaced. most of this, however, i can live with and replace piece by piece as i can afford it. The main problems im having are 1) engine looses power during "spirited driving" and 2)there may be an exhaust leak because i can smell exhaust from inside the cabin after driving for extended periods. to elaborate on the first part. if i baby the car and keep it in low rpm's it runs fine, idles just under 1k rpms. but if i push it at all, and get it past 3 or 4k rpms, it idles funny when i put the clutch back in, it will fluctuate between 500 and 1500 rpms and sometimes stall out completely, at which point i just re-start the car and its fine. i can usually keep it from stalling by easing it back down to 1k rpms or barely pressing the gas when its idleing rough to keep it around the 1-2k mark. i just took it to a nissan dealer and they said they wont even touch it because of after-market parts and the fact that it didnt have a stock wiring harness. they recommending taking it to a performance shop, but i dont know of any in the area (northwest indiana). they did tell me that the throttle position was out of adjustment and that the breather tubes were missing from the exhaust which is probably why i was smelling it. i know next to nothing about cars so i was hoping you guys could give me some advice. what to have checked out/replaced/etc. or atleast a good shop to take it to in the area. thanks guys

oh, couple things i just remembered, dont know if it will help or not. if the headlights are on when the idle is rough, they dim and brighten in synch with the rpms. outside of all this, i absolutely love the car. body is in perfect condition, fresh paint, no rust, the rubber around all glass is dry and probably needs to be replaced (dont know if it leaks, but i wouldnt be surprised), struts recently replaced, axles recently replaced. and when it runs its a blast to drive. im hoping i can have all repairs made for under a couple grand.

[Hodo]

Ok the idle problem does sound like the TPS going out. You may also want to do a throttlebody cleaning at the sametime.

Next the exhaust smell could be the breather tubes not being connected. But it could also be cracked flexpipes.

Headlights fluctuate with the RPMs.... Alternator going out on you. Not to uncommon. Check your powersteering lines make sure they arent leaking. Becuase they will get old and split and leak down onto your Alternator and kill it. And how do you know the rear swaybar has to be replaced. I dont hear of that going bad too often.... if ever. Usually its the swaybar endlinks or bushings. Also your IACV (Idle Air Control Valve) could be going bad, to options on this one... if your mechanicaly skilled you can take it off and clean it. (reminds me I need to do that) If you arent buy a new one.

Last thing, if your not sure when the timeing belt has been replaced get it done SOON! Replace the timing belt and the water pump and if it has more than 120K miles on replace the cam seals too. This will save the car for another 60K miles easily.

Goodluck and welcome to the wonderful and stressful world of the Z32!
Joy of driveing Generation Z!

[grg3135]

rear swaybar rusted through, its broken. as far as the tps goes, is that something that needs to be replaced? or just adjusted? and yeah, theres a decent p/s leak. it wasnt oil leaking, it was power steering fluid. how sure are you that the alternator is going out? the headlights wouldnt be related to the tps? i just spent 6 grand on the car and dont have a whole lot left for extra parts, im trying to make it stretch as far as possible.

[Hodo]

Easiest way to check the alternator is to get a voltmeter and connect it to the battery, and check the charging voltage with everything on and the car running. It should be around 14Vs at 2000RPM. If its fluctuating or less than 13.5Vs then its the alternator dieing on you.

Next the P/S leak is most likely the highpressure line leaking. Just going to have to replace that, last time I replaced one I think it was close to a 200dollar part. But that was about 6 months ago.... and in the automotive buisness thats a LONG time.

The TPS can be adjusted, the exact instructions can be found on twinturbo.net. Its pretty easy, but becareful the little screws that hold it in place, may break off. Then you will need to tap out the old screws or replace the throttlebody.
The TPS wouldnt cause a headlight problem. Unless your RPMs are dropping well below 500RPM.

Well start by checking the alernator. If that checks out adjust your TPS and clean your throttlebodies.