-
Grand Future Air Dried Beef Dog Food

Carnivore Diet for Dogs

Air Dried Dog Food | Real Beef
Go Back   Automotive Forums Car Chat > Nissan > 240Z | 260Z| 280Z | 300ZX (Past Z Cars)
Register FAQ Community
240Z | 260Z| 280Z | 300ZX (Past Z Cars) The original Z cars - ones that started it all.
Reply Show Printable Version Show Printable Version | Subscription Subscribe to this Thread
 
Thread Tools
  #1  
Old 12-07-2003, 08:24 PM
90na300zx 90na300zx is offline
AF Newbie
 
Join Date: Nov 2003
Posts: 30
Thanks: 0
Thanked 0 Times in 0 Posts
Send a message via AIM to 90na300zx
1990 300zx misfire problem

so heres the problem, spark plugs were changed about 7 months ago(platinum tipped). within the last 2 months my car has had a misfire that has gradually gotten worse which makes me think it is a fuel problem. its now gotten to the point where when i start the car, it will stull out unless i hold the rpm's around a grand for a couple minutes. when the car gets warmer, for some reason the misfire isnt "As bad", but u can definitely still feel it. has anybody else had this problem? i hope its not bad injectors, i think im gonna be taking it sumwhere to get it run on the diagnostics.
Reply With Quote
  #2  
Old 12-07-2003, 09:10 PM
rizzspeed's Avatar
rizzspeed rizzspeed is offline
AF Enthusiast
 
Join Date: Nov 2003
Posts: 200
Thanks: 0
Thanked 0 Times in 0 Posts
Send a message via AIM to rizzspeed
Re: 1990 300zx misfire problem

what kind of plugs are you using? Are they the right 'temp'? Were they gapped properly?

If that's all ok, check the timing. Check your Throttle Position Sensors. They might be corroded and be in need of cleaning. Make sure you don't have any vacuum leaks, so check your hoses.

If your car is a 90, like I'm assuming, the ECU is an OBDI not an OBDII. Therefore, running a diagnostic is an easy DIY procedure. Because of the age of the car you can't take it to a shop to have them hook it up to a machine. That only works on vehicles that were made in '95 and after. Go here to learn the diagnostic procedure.

http://www.ttzd.com/tech/diagnostictech.html
Reply With Quote
  #3  
Old 12-08-2003, 12:16 AM
90na300zx 90na300zx is offline
AF Newbie
Thread starter
 
Join Date: Nov 2003
Posts: 30
Thanks: 0
Thanked 0 Times in 0 Posts
Send a message via AIM to 90na300zx
i actually did that procedure already, bad TP sensor and o2 sensor codes came up, but that shouldnt be causing the car to miss as bad as it is, and the car smokes at around 4000 RPM and higher( which still makes me think its fuel)
Reply With Quote
  #4  
Old 12-08-2003, 07:34 PM
rizzspeed's Avatar
rizzspeed rizzspeed is offline
AF Enthusiast
 
Join Date: Nov 2003
Posts: 200
Thanks: 0
Thanked 0 Times in 0 Posts
Send a message via AIM to rizzspeed
Re: 1990 300zx misfire problem

well what do you think the TPS does? It tells the ECU how much air is coming in along with the MAF. If it's reading the wrong amount of air, it'll send the wrong amount of fuel. Same with the O2 sensor. The TPS might just need to have the connectors cleaned. The O2's will probably have to be replaced. Either that or check the wiring and make sure that it's not burnt, melted, and/or corroded.
Reply With Quote
  #5  
Old 12-11-2003, 11:24 PM
Gradyman25 Gradyman25 is offline
AF Enthusiast
 
Join Date: Sep 2002
Posts: 177
Thanks: 0
Thanked 0 Times in 0 Posts
Send a message via AIM to Gradyman25
i've had basically the same problem, and yes the 02 sensors will cause it to run bad, replacing them is a pain in the ass, but worth it, if your going to replace all that you might want to clean out your upper plenum, and your throttle boddies with a carb cleaner product, some are specifically designed for fuel injected cars, but if it hasent been done you really need to do it, plus with your bad sensors, its possible you fouled a spark plug, so check them again as well, and like rizzspeed said, make sure they're the right temp, but most of the new spark plugs for the Z come pre-gapped
Reply With Quote
  #6  
Old 08-23-2012, 02:36 AM
JohhnyB.Goode JohhnyB.Goode is offline
AF Newbie
 
Join Date: Aug 2012
Posts: 1
Thanks: 0
Thanked 0 Times in 0 Posts
Re: 1990 300zx misfire problem

@ rizzspeed, did you ever have this problem solved? if so, what was the solution? my Z is having the exact same symptoms. Misfire on cylinder 1, dumping fuel and smoke when the it goes past 3500 rpms, its auto put will "stall" if i dont keep rpms up, and after a while the misfire doesnt seem as bad but i can still hear it and there's smoke and fuel coming out the pipes. before i spend on anything or everything @ Gradyman25 said, i wanna know if its electrical; the sensors or wiring, or your Z just needed cleaning
Reply With Quote
 
Reply

POST REPLY TO THIS THREAD

Go Back   Automotive Forums Car Chat > Nissan > 240Z | 260Z| 280Z | 300ZX (Past Z Cars)


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 08:34 PM.

Community Participation Guidelines | How to use your User Control Panel

Powered by: vBulletin | Copyright Jelsoft Enterprises Ltd.
 
 
no new posts