NISSAN 300ZX Multiple Problems

86_gas_saver

86 300ZX nonturbo 5 speed with 140,000+ miles. Issues I've encountered that I could use some assistance with as follows:

Severe miss and won't idle when cold. After it warms up runs fine with occasional miss and rough idle. Had a friend pull coded. Gave TPS sensor code but he said he recommended taking to Nissan dealership before sinking $$$ into parts. Anybody have this same type of issue?? What was your problem??

Next issue: Just today, the tranny cracked and popped when in 2nd and now has harsh wine which goes away when I push in clutch. Sounds like perhaps input shaft bearing. Worth trying to rebuild or pickup used/reman tranny? If used/reman, where's the best place to get one?

3rd & final issue: Car has had a pretty severe thump in rear end when going across the least of bumps or even accelerating quickly from a cruise. I've put on hoist and can't find anything. Shocks?? Anybody have similar issue? What was problem?

Thanks in advance for any assistance you may provide.

pauld5

1) Do you know the number to the code?
2) Could be speedometer cable, My cable connection needs work. I'd check under the stands and see, also check the fluid level in tran case behind the right cylinder head case?
3) Does this occur when you turn and accellerate? There seems to be something wrong with my 86 similar with yours on this issue. Please keep me inform?

Not much help now, but lets look ahead and continue with forum disc?

pauld5

Is your Engine an E or an ET? :confuse:

86_gas_saver

Issue re: missing and no idle when cold is possibly the Coolant Temp Sensor according to what someone on another site told me. I looked up what it does and it makes sense. This sensor sends a signal to the cpu about the temp of the head/coolant which in turn regulates fuel. I ordered one for like $25 but haven't installed it yet.

Tranny issue...had a mechanic take it for a spin and it's definitely something bad in the tranny. It whines when sitting still in neutral or moving in most gears but especially 2nd. Mechanic said the main bearings in the tranny are worn (specifically he indicated main input shaft bearing) allowing the gears to slip apart causing the loud crack/bang noise. I ordered a tranny rebuild kit for $135.

Final issue re: thump in rear end upon quick accel/decel or over rough road is some bushings up under the rear.

Found all the answers to my questions at the following site: www.300zxclub.com

Go to the "Frequently Asked Questions" section for some great information as well as there's a thread in that FAQ section entitled "Repair and info sites" with 9 other sites listed with great information. One great site on that list is http://www.xenonz31.com/index.html

Good luck.

86_gas_saver

I haven't a clue whether it's an E or ET.

turnten

1) Coolant temp, TPS, and/or MAFS
2)Pilot bearing, input shaft bearing, ring gear, or a host of other bearings. Used tranny is cheap, and rebuilds can be messed up easy
3)99 percent chance it's the subframe bushings. The entire rear subframe sits on a few bushings. The front ones tend to go leaving a lot of movement and a metal to metal clunk

pauld5

On the radiator there is a sensor that tells the Electronic control unit (ECU) when to turn the fan on and off? Or when to adjust? You have to locate. Trottle Position Sensor (TPS) Located on the trottle air intake near the Trottle cables i.e. one for the gas peddle and one for the choke. A little square black b plastic ox 2"x1.5"x 0.5" Replace but don't turn the new unit axil on installing, will damage. Last the Main Air Flow Sensor (MAFS) this is after the air cleaner filter follow the air line 3" dia. until you find the fixed box with black plastic top. Terrible too replace, good luck:?

dennis1029

Regarding the thump in rear end. Check your Body mounts. There is a rubber bushing or shim. mine was rotted out, replaced it with a chunk of hard rubber about 1/2 the size of a hockey puck. The problem went away and it took about 1/2 hour to do.

roliv46

I have 1990 300zx,when I accelerate hard it hesitate and and shutoff.after it sit for awhile,it will startup.Not sure what the problem or problems could be.