P0400 EGR flow Code

[97Trans-AM]

Disconnect both terminals on your battery and touch them together for about 10 seconds (don't touch the battery when you are doing this). This discharges any capacitors in the system. Then hook your battery back up, and your PCM will default back to factory settings. Over time they learn driving habits and other crucial info from their environment for better performance. I recommend doing this when buying a used OBDII vehicle and when moving so your PCM can adapt to its new home/driver.

[Captainofiron]

Originally Posted by 97Trans-AM

Disconnect both terminals on your battery and touch them together for about 10 seconds (don't touch the battery when you are doing this). This discharges any capacitors in the system. Then hook your battery back up, and your PCM will default back to factory settings. Over time they learn driving habits and other crucial info from their environment for better performance. I recommend doing this when buying a used OBDII vehicle and when moving so your PCM can adapt to its new home/driver.

ok I will give it a try, to I need to leave it unplugged for an extended period? or just touch them and hook it back up?

[Bennylava]

Thread necro.

I am having the same problem on my 96 Firebird formula. I can't seem to figure out what is causing this flow issue. Can I just put my hand over the top part of the EGR valve where the tube connects, to check for vacuum?

I also have longtube headers. They have a bung and everything but we are having a pinch issue with the tube that comes off of there.

[Captainofiron]

Originally Posted by Bennylava

Thread necro.

I am having the same problem on my 96 Firebird formula. I can't seem to figure out what is causing this flow issue. Can I just put my hand over the top part of the EGR valve where the tube connects, to check for vacuum?

I also have longtube headers. They have a bung and everything but we are having a pinch issue with the tube that comes off of there.

I still havent fixed this, I was rebuilding my exhaust system (im thinking that my cutouts were causing back pressure problems in the primary where the EGR connects and causing the computer to think the EGR was acting up.)

BUT while I was working on this my OPTI took a crap, and since I just moved and was remodeling the new house, I hadnt had any time to work on it, now that the garage is not filled with boxes and furniture, I have started to work on it again.

I really think there is a leak which is causing the code