Idle concerns - ZR-1 Net Registry Forums

Jim Nolan · 11-30-2009

With the cams reset after full porting will there be a lope in idle? The RPM is about 900. The second issue is when I get on it there seems to be little difference with key on or off, RC injectors installed 2 years ago. I am debating wether to pull the plenum off and check the secondary advance. I put a vacuum gage on with engine running and it holds about 23 hg. SW headers also. Any thoughts.

jonszr1 · 11-30-2009

i dont think you should have any lope , my callaway car has the cam timing redone and its smooth. by advance you do mean the opening of the secondary vac system???/when you turn the car on does the pump go on and then stop ?what year is your car????if its a 91-95 do you have the prom changed so the valet key is allways on ???.you might ck the fuse for your sec system its on the drivers side wheel well if its a 90 . sounds like your valet key is either turned off , switch is bad or fuse is out. other chime in ,but thats what little i know hope it helps

Jim Nolan · 11-30-2009

The e-prom has been reflashed but not for constant key on. I can go key on during hard acceleration and feel a little more power but not much. I was wondering if the secondaries on one side were not working would it just be a lack of power or a noticable miss or what. At idle it may look like a lope or a miss but no miss is noticed at full throttle. The pump does go on then off. It's a '92

11-30-2009

Jim, when you say lope, is the whole car shaking? Or can you just hear the lope in the exhaust?

Jim Nolan · 11-30-2009

The engine has a has a slight even shake that reminds me of my old '66 327/350.

11-30-2009

Sounds like a miss. Check spark.

Kb7tif · 11-30-2009

Let it warm up real good Listen to your tailpipes for a miss.. Both sides should be close.

ZR1ROB · 11-30-2009

you should feel a little lurch around 3K. if not, your secondary system isnt coming on. maybe the key circuit - a tech1 will tell you that. The green light is controlled by the ECM so if you see it, then the key circuit is working - the tech1 really isnt necessary for that. spark was mentioned, check your plugs - make sure they are torqued to spec - 20Nm. and make sure the plug wires are connected securely. It could be your secondary fuel pump is bad, or the relay for the secondary injectors is bad, or a wire is cut. Any codes? check your fuel pump fuses - there are two. and check the injector fuses, 2 too! sooty black exhaust? again, maybe a bad plug or wire.

Demps · 11-30-2009

Jim,
Come over to Ft Walton and we'll check it out.
Ted

Jim Nolan · 12-01-2009

Where at in Ft. Walton. I'm pretty familiar with the area as I lived there for 20 years.

11-30-2009	#1
Jim Nolan Join Date: Jan 2007 Location: Florida Posts: 240	Idle concerns With the cams reset after full porting will there be a lope in idle? The RPM is about 900. The second issue is when I get on it there seems to be little difference with key on or off, RC injectors installed 2 years ago. I am debating wether to pull the plenum off and check the secondary advance. I put a vacuum gage on with engine running and it holds about 23 hg. SW headers also. Any thoughts. Last edited by Jim Nolan; 11-30-2009 at 01:51 PM.

11-30-2009	#2
jonszr1 Join Date: Sep 2006 Location: lone pine and mammoth lakes Posts: 1,406	Re: Idle concerns i dont think you should have any lope , my callaway car has the cam timing redone and its smooth. by advance you do mean the opening of the secondary vac system???/when you turn the car on does the pump go on and then stop ?what year is your car????if its a 91-95 do you have the prom changed so the valet key is allways on ???.you might ck the fuse for your sec system its on the drivers side wheel well if its a 90 . sounds like your valet key is either turned off , switch is bad or fuse is out. other chime in ,but thats what little i know hope it helps

11-30-2009	#3
Jim Nolan Join Date: Jan 2007 Location: Florida Posts: 240	Re: Idle concerns The e-prom has been reflashed but not for constant key on. I can go key on during hard acceleration and feel a little more power but not much. I was wondering if the secondaries on one side were not working would it just be a lack of power or a noticable miss or what. At idle it may look like a lope or a miss but no miss is noticed at full throttle. The pump does go on then off. It's a '92

11-30-2009	#4
Jeffvette Guest Posts: n/a	Re: Idle concerns Jim, when you say lope, is the whole car shaking? Or can you just hear the lope in the exhaust?

11-30-2009	#5
Jim Nolan Join Date: Jan 2007 Location: Florida Posts: 240	Re: Idle concerns The engine has a has a slight even shake that reminds me of my old '66 327/350.

11-30-2009	#6
Jeffvette Guest Posts: n/a	Re: Idle concerns Sounds like a miss. Check spark.

11-30-2009	#7
Kb7tif Join Date: May 2009 Location: S Nevada Posts: 351	Re: Idle concerns Let it warm up real good Listen to your tailpipes for a miss.. Both sides should be close.

11-30-2009	#8
ZR1ROB Join Date: Oct 2006 Location: Tijeras, NM, USA Posts: 23	Re: Idle concerns you should feel a little lurch around 3K. if not, your secondary system isnt coming on. maybe the key circuit - a tech1 will tell you that. The green light is controlled by the ECM so if you see it, then the key circuit is working - the tech1 really isnt necessary for that. spark was mentioned, check your plugs - make sure they are torqued to spec - 20Nm. and make sure the plug wires are connected securely. It could be your secondary fuel pump is bad, or the relay for the secondary injectors is bad, or a wire is cut. Any codes? check your fuel pump fuses - there are two. and check the injector fuses, 2 too! sooty black exhaust? again, maybe a bad plug or wire.

11-30-2009	#9
Demps Join Date: Jan 2006 Location: Niceville Posts: 1,001	Re: Idle concerns Jim, Come over to Ft Walton and we'll check it out. Ted

12-01-2009	#10
Jim Nolan Join Date: Jan 2007 Location: Florida Posts: 240	Re: Idle concerns Where at in Ft. Walton. I'm pretty familiar with the area as I lived there for 20 years.