20 Most Recent 1985 Nissan 300ZX - Page 6 Questions & Answers

I HAVE THE SAME PROBLEM WITH A 1985 AUTOMATIC NON-TURBO. I READ ON ANOTHER WEB SITE THAT SOME GUY HAD REPLACED ALL KINDS OF STUFF AND IT ENDED UP BEING A TRANSMISSION COMPUTER LOCATED IN THE BACK OF THE CAR BEHIND THE SPARE TIRE. SAID HE RESOLDERED THE CONNECTIONS AND THE PROBLEM WENT AWAY. GUESS I NEED TO CHECK IT OUT AND SEE IFIT SOLVES MY PROBLEM. I WILL LET YOU KNOW IF IT HELPS ME OUT.

this old ??1985 ?? try the classic vehicle magazines

You will need ratchet and socket set, something to help hold the alt.(alternator) when tightening the belt ( like a pry bar). Loosen the bolts around the alt.. now it will move, and you need that prying tool now. use it to move the alt. so the belt has about an eighth of an inch of play. holding it there, tighten the bolts back (nice and snug). Never over tighten the bolts, they can snap on you. now start the car, and you should see the belt is not slipping any more. This job will take you about 20 to 30 minutes.

suspect 1) bad spark plug(s) - change whole set if needed, (2) failing ignition coil (3) failing
distributor component(s), or (4) worn out distributor cap and/or rotor - if these need to be changed,
change both the cap and rotor as a set.
COST: if yo do any of these repairs yourself, your parts costs would be fairly low, but getting a garage
to rebuild your distributor could be costly

it is in the fuel tank try using the trap door in the trunk.

almost certainly the fanbelt is in need of replacement/tightening,on this car the alternator is the adjuster,loosen the bolts,lever the alternator away from the engine and then tighten the bolts.DO NOT OVERTIGHTEN THE BELT.1/2" play in the longest run is fine.

the timing chain tensioner is hydraulic and either out of adjustment or defective.  You need to remove the timing chain cover and reset the mechanical correlation between the crankshaft and the camshafts.  also the other ignition time marks are on the crankshaft harmonic balancer and the cam cover.  Do not crank the engine with the timing out of sequence or you'll destroy the engine.

find a nissan dealer and buy a new lock cylinder, have them set the tumblers for you then find a video of someone installing one over on youtube.com and put it in. a dealer can put one in for you for less than a hundred bucks, but having them set the tumblers to match your original keys is extra.

I dont believe you have a fuel temperature sensor in the vehicle. I have never heard of one of those. You have a collant temperature sensor, but this does not sound like the problem. You state that it runs fine at idle and putting around town it is ok. I would start by putting a fuel pressure guage on the fuel system and measuring your fuel pressure under various loads. If the pump output drops to below acceptable limits then I would look at replacing the fuel filters first and doing the test again. If that does not work I would look at the fuel pressure regulator, if that is bad it could be dumping fuel or not providing enough under load. You can test is with a hand vacuum pump (mighty vac) it should hold vacuum. If that is not the culprit I would look at the fuel pump.

I would fix the leaking injectors first. It is a known problem and it is kinda hard to fix other fuel problems when the entire system is not working correctly. If your computer is throwing codes then you need to replace the parts that are causing faults. I would start with replacement of the faulty injectors and then replacement of the parts that are throwing trouble codes. Once you replace the injectors I would clear the codes from the ecu and drive it. See if it throw more codes before replacing any other parts.

I would start by checking the end that goes into the transmission and see if the plastic gears are worn out. It is usually easier to remove this from the transmission and see if it works by turning it to see if you get any movement in the speedometer in the dash. It is much harder to pull the dash out to see if there is a problem with the connection there.

Exhaust valve springs are beginning to weaken. Replace if you plan to continue to run at that RPM or you will be sorry. Things fly apart going that fast...

The heads of the screws are sheared off for obvious reasons(theft etc) you can drill them and use an easy out... When you replace the bolts be sure to use the correct ones and shear the heads off of them to ensure your cars security

Hi:
The fuseable link is a high amperage rated circuit, that will blow, or open, if the current is too high. When that happens, you won't have any 12v power on that circuit. You can check them with a multi meter, with the battery disconnected.

UNfortunately, due to the extremely tight and cramped conditions surrounding the motor......you will need to remove the engine to perform any major engine work.

I

Had a 1986.. same problem.. there is supposed to be a ground cable from the motor to the frame.. if this ground is disconnected.(or not connected well). the motor will not start even if there is gas and spark (which I am assuming that you have already checked), if not, make sure that your coils are firing, the coils sometimes are a problem on this car (if I remember correctly), check your fuel, make sure your fuel pump is working and that the filter is not plugged.......

sounds like a restricted exhaust
quite possibly the cat
disconnected the exhaust and retest

i have that exact problem with my 85 z. did you ever figure out the problem? [email protected]

Sounds like you have a slow (high-resistance) short in your electrical system. Tracking them down can be a real pain. The best bet would be to have a mechanic find and fix it. If you're the enterprising type, you can begin going over it with a multi-meter. Or, if you want the easy/cheap way out, you just put a big switch inline with one of the battery terminal cables, and use it as an on/off switch for the car.