ToxicZ

Just got the head back on and I'm not sure about all these vacuum lines. Car is an 81 with 240sx TB. Will only start with plenty of gas, runs with a fair bit of backfiring and dies as soon as the throttle is let off.

Today I made sure my timing was correct. Set the crank pulley to zero degree marker and set the cam to TDC (rabbit ears on cylinder 1). As per cleaning up the intake manifold I have removed air regulator, mixture screw assembly and capped off all manifold ports except for charcoal canister and fuel regulator. Plugged the big port on the TB and the small one goes to the vacuum advance.

Spark plugs are all new, injectors rebuilt with all new fuel lines and rail. Does anyone have good pics of the vacuum port area of the TB and advance?

ToxicZ

Nevermind! My brain was missing a critical piece of information. Car gets much better mixture when you plug in the AFM. Now for a hot valve adjustment and I'll finally drive this thing after too many months of waiting.

skittle

ohhh yeah that would do it.

thxone

Make sure the AFM is plugged in....

ToxicZ

Yepp, I'm a smart guy. Still rough, but now it's just down to timing (and possible vacuum leaks). Timing notch is pretty much exactly in line with the dash, on the #2 position but general consensus leans towards having the notch just to the right of the dash, so my timing may be advanced slightly. Pulls very well in the operating range (2500-6500) but just doesn't idle worth **** and smells like fuel.

jmmorriso

Id say if everything else is new, get a new AFM. Rod said it did wonders for his Z Thats what Im down to on mine too

hoov100

why not do a MAF conversion?

ToxicZ

A MAF conversion is in the cards, but the AFM was working correctly before, and I have inspected the internals and adjusted the wiper for good contact. I will be doing some comp. testing and timing adjustments this weekend so I'll see what comes of that.