280Z EFI Inconsistent Idle

BenjEtch

Club Member
Hi guys, me again doh!

Sourced a new AFM for the Z which seems to be working fine which is great. What I did notice is that the car is now idling really inconsistently. It's all over the place.

Here is a couple of video of the idle, recorded one after the other it sounds like it loses a cylinder on the second video too.

Things I have done:
- Checked fuel pressure (fluctuating between 32-35 PSI)
- Checked for vacuum leaks and subsequently replaced a few hoses.
- Performed all of the checks on page 38 of the EFI Bible

I did find that the 2nd circuit test which is on page 48 (screenshot attached) resulted in continuity at both part and full throttle, which points to the throttle valve switch - could this have something to do with the inconsistent idle? I checked the connection and pulled off the plastic plate and all looks okay?

Any thoughts would be greatly appreciated - can't wait to get rid of this pesky efi system.
 

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Fairlineguy

Club Member
I would normally start by checking it’s not drawing air from some where.
put your hand over the air intake at idle and stifle the engine of air if it’s got a leak you’ll hear it normally sucking from some where
 

BenjEtch

Club Member
I would normally start by checking it’s not drawing air from some where.
put your hand over the air intake at idle and stifle the engine of air if it’s got a leak you’ll hear it normally sucking from some where
Good idea, I'll give that a go thanks
 
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