Surging P/N Idle, rough start
Thread Starter
Supreme Member
Joined: Feb 2000
Posts: 1,170
Likes: 0
From: Seattle, Washington
Car: '87 IROC-Z/'82 RX7
Engine: SBC 355/1.1L Rotary
Transmission: T56/5 Speed
Axle/Gears: 4.33/3.93
Surging P/N Idle, rough start
Here goes:
'87 350 TPI 165 ECM $32B
Thus far I have reprogrammed my chip to compensate for the 24lb SVO Injectors I've installed and the 350.
The car was originally a 305.
The Cam: Comp XE262h-4 Dur 218/224 on a 114ēLSA
When I start the car it takes more cranks over than I would like.... the Rpm goes to 900 and then drops straight to 500 acting like it wants to die, running very rough, then after about 10seconds raises up to 700 and much smoother.
When the car is fully warmed up, if I am in park/n the idle will wander from 500-800 surging.
My IAC counts go from 20-40
The Spark from 19.9-27
Then for a few seconds it will idle fine and steady at 550... then surge again, and again with the changing IAC and Spark
I've set the IAC low as I've read to do in this forum. The motor is also clean and not sticking.
The ignition is upgraded with an MSD 6AL, Blaster Coil, New cap, rotor, plugs, wires.
When I am in Drive, the car idles fine at about 530. Put it back in P/N and it raises the idle a tad and surges.
Where do I go from here? I was told the cam might need a higher idle, but if so, why does it idle fine in GEAR at a lower idle than P/N?
'87 350 TPI 165 ECM $32B
Thus far I have reprogrammed my chip to compensate for the 24lb SVO Injectors I've installed and the 350.
The car was originally a 305.
The Cam: Comp XE262h-4 Dur 218/224 on a 114ēLSA
When I start the car it takes more cranks over than I would like.... the Rpm goes to 900 and then drops straight to 500 acting like it wants to die, running very rough, then after about 10seconds raises up to 700 and much smoother.
When the car is fully warmed up, if I am in park/n the idle will wander from 500-800 surging.
My IAC counts go from 20-40
The Spark from 19.9-27
Then for a few seconds it will idle fine and steady at 550... then surge again, and again with the changing IAC and Spark
I've set the IAC low as I've read to do in this forum. The motor is also clean and not sticking.
The ignition is upgraded with an MSD 6AL, Blaster Coil, New cap, rotor, plugs, wires.
When I am in Drive, the car idles fine at about 530. Put it back in P/N and it raises the idle a tad and surges.
Where do I go from here? I was told the cam might need a higher idle, but if so, why does it idle fine in GEAR at a lower idle than P/N?
Thread
Thread Starter
Forum
Replies
Last Post
