Hey, I am new I picked up a 85 300ZX non-turbo last week.

My car is running rich for one
secondly, it has a very rough idle (hot or cold) (the car will idle at the 700-1000 rpm and it seems to be random on either rough or not)
third, it accelerates in stages almost, you can feel when it is bogging down and then it will pick up, and then bog down again and pick up again.


You can hear a fuel injector(s)
The clutch was apparently put in 10 000KM ago, however it won't engage till you are near the top of the clutch. Any suggestions on that?

I replaced the PCV, Spark plugs, wires, rotor, distributor cap, fuel filter, oils, air filter and exhaust the first day I had the vehicle.

Where can I get performance parts for these cars? Are any on the internet? I just want to buy the standard bolt on parts

 

fuel injector cleaner?

 

Crazy question but how do you know it is running rich?

 

Probably has an air to fuel ratio gauge

 

intake or exhaust leak

 

Fuel is coming out of my exhaust. The car is NA. When it is cold all you can smell is the gas coming out of the exhaust.

I have to let the car warm up till it is drivable.

New muffler system and new intake system. good guess though. I am swapping out the O2 sensor today. I hope that helps a little. Either way it is covered in the extra gas I imagine.


Pete

 

I would pull out each spark plug and see which ones are wet. If only one is wet you have the cylinder with the problem. If it turns out all are wet then you have a fuel delivery problem possibly caused by a bad sensor.

 

Thanks. Unfortunately I just changed them the other day. All were dry.

Pete

 

Okay, they were dry but how black were they?

 

not black either. They were a little hot (ie white) but thats it.

Pete

 

So, the car is running rich but there are no signs of it on the plugs. That makes no sense.

 

So, let's get something straight. Can you actually see gas coming out or are you just smelling it? Did you happen to change catalytic converter or just behind the cat when you replaced the exhaust?

 

haha yeah sorry to be difficult. There is no cat. Just a resonator and it was from the headers back. But all of it is new.

it MAY not be fuel coming out of the exhaust, however there is a liquid that comes out of the exhaust. It only does this till the car warms up. To be honest I'm not sure it is fuel, it has a small hint of gas smell to it.

between 1000 and 2000 RPM the car bogs down and stutters. It seems like it is getting way to much fuel. when it warms up it drives normal.

Maybe it isn't a fuel thing at all?

thanks so much guys,

Pete

 

the liquid isa probably condensation, which is perfectly normal.. the reason it has a gas smell to it is that its been in your exhaust. the stuttering before warm up sounds like, correct me if im wrong guys, your cylinder head temp sensor. check your ecu codes, if you get a 13 its the chts.

 

check sensor

 

actually, i have a copy of the service manual, and it says the cars equiped with a fuel pressure regulator that has a small one wire sensor hooked to it. if the sensor is bad(open thermistor) it will run rich. i have the same problem. problem there is you can't just buy the sensor. you have to buy the whole pressure regulator.

 

I was just trying to see if the car really was running rich which I doubted b/c the plugs were dry and white. Mine was stumbling down low and my plugs were white and I replaced the fuel filter and it cleared right up.

 

I will check both of those out. thanks guys. Now I just have to wait till pay day. haha


Mellow, I changed the fuel filter too

 

yes, but his problem is only before it warms up, not all the time. mine does the same thing, i've just been too lazy to mess with it and just let my car warm up. fsm and everything else ive heard sez chts not fpr. bet he throws a code 13.

 

Hey guys, sorry for no updates. I have been a wee bit short of cash between jobs. Anyways I meant to add to the fact that the car will idle better if you turn the heater on.

Pete

 

I just had this happen to my 1984 300ZX Turbo.

Exactly the same issues that you describe. The problem with mine was the mass air flow sensor, (rigid wire type in the 84). It was going bad, and the problem progressively got worse.

It started out as a cold only issue, then began to effect driveability, until the car would bog down even when hot.

I took it to a dealership to find out the problem after suspecting the plugs, injectors, fuel pump, vacuum fuel flow control, and just about EVERYTHING else...

Long story short, get a book on your car, and look at the diagnostics on the engine conmputer. It will save you the $$ I spent at the dealership.

Good luck

 

Does it immediately idle better when you turn on the heat or after a few minutes?

 

Mine originally Idled better when the motor was warm, but I suspect that was due to other factors, such as the O2 sensor and the Mass Air Sensor warming up and changing the fuel flow...

Since it's been fixed, the only problem I have now is overheating... but I know what's wrong there... need to flush the radiator, and fix the cooling fan.

That's my 2¢, YMMV.