1984 Rough Acceleration under 2,300 RPM

[CapeCod911]

I have an 84 911 3.2 that is having some issues that are driving me NUTS. I just had a rebuild and the engine has been fully resealed, so I know it's not an air leak.

Car starts fine, but does not accelerate smoothly until over 2300 rpms. The engine bucks and won't accelerate smoothly.

his occurs for about 1 to 2 seconds and then the engine picks up a and runs smoothly as I accelerate. I can run it all the way up to red line with no problems and it has full power. But, at idle a rough start unless I gas it above 2500 again.

Any thoughts on this? Does this sound like a sensor issue, bad relay, DME???

Peter

[Discseven]

Peter... Was there anything like this prior to the rebuild? What electronic stuff was replaced if anything? Did you replace injectors?

[RobFrost]

Peel back the rubber on the AFM connector so it's still powered up, pierce the insulation on the wires and probe them with a voltage meter. Check the voltage goes smoothly from the low to the high reference values as you open the AFM flap by hand.

I don't know the reference values off hand.

Sent from my SM-G988B using Tapatalk

[917_Langheck]

What is the status of the O2 sensor?

What is the status of the closed throttle switch?

Just because the engine was resealed does not eliminate the possibility of an air leak from the multitude of sources sitting on top of it.

[proporsche]

sound exactly like your air flow meter carbon-rails are a little worn out..You can gently relocate the wiper-contact position so it slides on a different place on carbon plate....
example here what to look for