[Fstgreg]

I have a 77 that I cleaned up the engine compartment and waxed the painted sections of. A week later I was pulling it out for a cruise and it surges at 2700 rpm. Possibly I moved a connection while waxing or water might have damaged something? Any help would be appreciated. I do have the manual, and didn't find anything of help. Maybe someone could steer me in the right direction. Thanks!!!

 

[RIK260]

My 78' would surge at around 2500 rpm. The fix was to adjust the TPS (throttle position switch) See your manual, it's a pretty simple process. Good Luck!

Richard
Woodland, CA

 

[RIK260]

Check the TPS (throttle position switch) Your manual should have the procedure for making the adjustment, it's pretty simple. Good Luck!

Richard
Woodland, CA

 

[aren77z]

You might also check your fuel filter.

Aren77z
'78 280z (Col. Mustard)

 

[Fstgreg]

I did check both the TPS, and the fuel filter has been replaced. Anyone else? This is even keeping me from taking to a shop to get it looked at. I am at a loss for answers. Thanks!!!!!!!!!!!!!!

 

[Fstgreg]

One more thing I noticed is that when it surging, (sounds like the fuel is being completely cut off) when the RPM drops if I floor it, it will backfire through the throttle body. It sounds like the fuel is cut off, then on, then off, etc... but idles great up to 25oo RPM.

 

[79-280-ZX]

Interesting.

What does your fuel pressure gauge (installed between the fuel filter and the fuel rail) read when this happens.

Wayne Monteath
Masham, Quebec.

 

[yo2001]

check vacumn advence my used to do that and it was vacumn advence

 

[johnh240]

Check connections to, and operation of the EGR valve. With backfiring from the intake sounds like an air leak.