Running Rich, Need Advice
03-01-2009, 05:19 PM
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Running Rich, Need Advice Hey all,
I just recently did Pacesetter Longtubes and an ORY on my 98 Z28. I deleted the AIR and EGR and drove the car around for maybe a couple hundred miles. Before the install it had been getting average mileage (about ~16 mpg in the city), with just a TSP Rumbler catback and an SLP lid.
After the header install the car netted about ~11 mpg on my last fill up, and smells rich in the exhaust. It runs fine as far as throttle response and pick up. My main concern was that I just re-did the job to add poly motor mounts and a few other things, and when I pulled the plugs they smelled like gas and the electrodes were slightly blackened in certain spots. The plugs themselves are primo AC Delco Platiums and are only about 2k miles old.
So, my question is this: do the longtubes and deleted emissions equipment just cause the car to naturally run richer on a stock tune? If I send out for a mail-order tune can I expect the fuel tables to be tweaked to compensate for this and possibly bump my mileage back up to a respectable level? Any input any one has would be appreciated. Thanks!
I just recently did Pacesetter Longtubes and an ORY on my 98 Z28. I deleted the AIR and EGR and drove the car around for maybe a couple hundred miles. Before the install it had been getting average mileage (about ~16 mpg in the city), with just a TSP Rumbler catback and an SLP lid.
After the header install the car netted about ~11 mpg on my last fill up, and smells rich in the exhaust. It runs fine as far as throttle response and pick up. My main concern was that I just re-did the job to add poly motor mounts and a few other things, and when I pulled the plugs they smelled like gas and the electrodes were slightly blackened in certain spots. The plugs themselves are primo AC Delco Platiums and are only about 2k miles old.
So, my question is this: do the longtubes and deleted emissions equipment just cause the car to naturally run richer on a stock tune? If I send out for a mail-order tune can I expect the fuel tables to be tweaked to compensate for this and possibly bump my mileage back up to a respectable level? Any input any one has would be appreciated. Thanks!
03-01-2009, 08:03 PM
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The ORY will make it smell rich even if it's not. But most likely it is running rich. Are you getting a SES light? If it's so rich that the computer cannot adjust fueling to correct it due to the preset boundaries, it should throw a code. The only way to really know is to hook up a wideband. A good tune would put your AFR where it should be, and you would most likely pick up some power as well.
03-01-2009, 10:09 PM
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Its throwing codes associated with the emissions equipment that has been removed (egr circuit low voltage, air circuit low voltage, 02 sens 2 banks 1 and 2 low voltage). Its not throwing any rich or lean codes nor any misfire codes. I figure the mods on the car just need a tune to set the fuel tables to where they should be.
