Extreme rich condition - ZR-1 Net Registry Forums

Perry Mitchell · 06-25-2020

Before any work was done and before the plenum was removed, the motor ran extremely rich. After talking with Marc and Jerry, I removed the plenum and eliminated the complete secondary system. I replaced all the injectors with FIC ones and the fuel pressure regulator with Jerry's new and improved unit (which I have to say is a work of art). The prom was re-calibrated by Marc and a resistor was installed between pins B22 and C18 on the computer which got rid of the code 66 that I had. I now have NO codes but still have the extreme rich condition. I suspect a failed sensor or vacuum leak but with all the vacuum stuff removed and ports capped off, I am at a loss. Any ideas?

-=Jeff=- · 06-25-2020

How are you detecting the rich condition? Are you using a scan tool? if so, do you have logs?

XfireZ51 · 06-25-2020

https://www.zr1.net/forum/showthread...ght=OBD1+codes

What's a code 66?

Perry Mitchell · 06-25-2020

A code 66 is a power fault for the valet switch.

Perry Mitchell · 06-25-2020

I do not have a scan tool but what I did was jump the terminals A and B in the ALDL connector and it showed no fault codes, only the code 12. All the plugs are black and sooty and the exhaust is very black and rich. I can't let it run very long as it smokes us out of the area.

XfireZ51 · 06-25-2020

Quote:

Originally Posted by Perry Mitchell

I do not have a scan tool but what I did was jump the terminals A and B in the ALDL connector and it showed no fault codes, only the code 12. All the plugs are black and sooty and the exhaust is very black and rich. I can't let it run very long as it smokes us out of the area.

Have u checked coolant temp sensor, not the gauge sensor?

Dynomite,

Need to add Code 66 to ur list of MALF in stickies.

Perry Mitchell · 06-25-2020

No, have not checked the coolant sensor. Can I do that without removing the plenum? It is rich right at startup.

PhillipsLT5 · 06-25-2020

Were the FIC injectors new or rebuilt?

Perry Mitchell · 06-25-2020

Quote:

Originally Posted by PhillipsLT5

Were the FIC injectors new or rebuilt?

I assume they were new as I bought them from Jerry and I am sure he would have told me otherwise.

XfireZ51 · 06-25-2020

Also, have u looked at Fuel Pressure Regulator. Can u put an FP gauge on the right hand fuel rail?

06-25-2020	#1
Perry Mitchell Join Date: Nov 2018 Location: Washington Posts: 98	Extreme rich condition Before any work was done and before the plenum was removed, the motor ran extremely rich. After talking with Marc and Jerry, I removed the plenum and eliminated the complete secondary system. I replaced all the injectors with FIC ones and the fuel pressure regulator with Jerry's new and improved unit (which I have to say is a work of art). The prom was re-calibrated by Marc and a resistor was installed between pins B22 and C18 on the computer which got rid of the code 66 that I had. I now have NO codes but still have the extreme rich condition. I suspect a failed sensor or vacuum leak but with all the vacuum stuff removed and ports capped off, I am at a loss. Any ideas?

06-25-2020	#2
-=Jeff=- Join Date: Jul 2007 Location: Bartlett, IL Posts: 7,158	Re: Extreme rich condition How are you detecting the rich condition? Are you using a scan tool? if so, do you have logs? __________________ 1990 Corvette ZR-1 #1051 Watson Headers (2" Primary) - Flowmaster Cats - Borla Catback Late Model IH - Plenum Coilovers - 4.10s Shelby Series 1 - Wilwood Brakes Custom Interior NCM Lifetime Member #978

06-25-2020	#3
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,685	Re: Extreme rich condition https://www.zr1.net/forum/showthread...ght=OBD1+codes What's a code 66?

06-25-2020	#4
Perry Mitchell Join Date: Nov 2018 Location: Washington Posts: 98	Re: Extreme rich condition A code 66 is a power fault for the valet switch.

06-25-2020	#5
Perry Mitchell Join Date: Nov 2018 Location: Washington Posts: 98	Re: Extreme rich condition I do not have a scan tool but what I did was jump the terminals A and B in the ALDL connector and it showed no fault codes, only the code 12. All the plugs are black and sooty and the exhaust is very black and rich. I can't let it run very long as it smokes us out of the area.

06-25-2020	#7
Perry Mitchell Join Date: Nov 2018 Location: Washington Posts: 98	Re: Extreme rich condition No, have not checked the coolant sensor. Can I do that without removing the plenum? It is rich right at startup.

06-25-2020	#8
PhillipsLT5 Join Date: Aug 2005 Location: Scottsdale, AZ Posts: 2,446	Re: Extreme rich condition Were the FIC injectors new or rebuilt?

06-25-2020	#10
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,685	Re: Extreme rich condition Also, have u looked at Fuel Pressure Regulator. Can u put an FP gauge on the right hand fuel rail?