i have a 83 280zxt and the past month or so it has been fouling out plugs due to to much gas, anyone know a sensible place to start troubleshooting to save me a lil time?

 

Back your foot off the gas pedal....sorry, I couldn't resist....check the O2 sensor.

 

Check your AFM (See the sticky above on cleaning the AFM). What do your plugs look like?? Pics would help there! Get a Haynes manual and check out some of the OHM checks you can do on some of the intake components, including the Air Flow Meter (AFM), TPS (Throttle Position Sensor), and other heat related sensors around the engine compartment. Also, make sure your vacuum lines are intact!!!

If all that checks out. come back for more info, as we are here to please!

Carl's Z

P.S. Go cheapest route first, then go from there!!!

 

install after the fuel filter a permanent fuel pressure gauge, a must for do it yourself people, or have the pressure checked, if FPR is acting up pressure will fluctuate, in your case will rise (from normal around 30 to 60's)...

 

My buddy just purchased a 280ZX 2+2 that was doing this horribly. it would run for about 30 minutes before fouling the plugs. I tried swapping out the head temp sensor and cleaning all the contact and resetting the timing and etc...
Finally I pulled the cap and it was toast. Weak spark makes for fouled plugs.

 

here are some pics.. plugs are three weeks old

 

Dude! Not trying to be mean...but those pics suck...99% of all digital cameras have a macro setting for just such shots. It should look like a flower on the camera...retake the pics only this time use the macro and a darker background and let the camera focus....I want to see these plugs.

No Macro
Attachment 5694

With Macro
Attachment 5695

 

i thought the turbos have a maf not an afm???

 

On the 300zx your correct but 280 zxt are afm.

 

ahhhh okies

 

sorry bout the pics here are some better ones that have been wiped a little


http://i31.photobucket.com/albums/c3...8/HPIM0421.jpg


http://i31.photobucket.com/albums/c3...8/HPIM0420.jpg


http://i31.photobucket.com/albums/c3...8/HPIM0417.jpg

 

Those plugs look ok to me.

 

get some NGK's

 

Yeah Those Plugs Are Fine.... Wait Till I Post Pics Of Mine.

 

look at the pix of zachs plugs, those are fouled, the ones you have look o.k. whats your gap set at, too large can cause odd problems

 

Yeah Same With Too Small... If You Don't Have One Get A Haynes Manual They Are Invaluable