Diesel Place banner
1 - 3 of 3 Posts

·
Registered
Joined
·
3,808 Posts
If you are getting an EGR code you have not deleted it properly. It might be the cause of de fueling but I am not sure.
EGR codes tripped in my truck always made it run worse. Its programed in that way so you will get it fixed. Because its emissions.
How exactly did you delete it? You cant just un hook stuff. You should get a new chip for the PCM with EGR deleted.
But on OBD1 trucks sometimes you can get away with leaving the Baro sensor hooked up to the vacuum line. If you have done a vacuum pump delete. You need a new chip.
 

·
Registered
Joined
·
3,808 Posts
This is how the EGR system operates.
When at a steady cruise above 45 MPH . The PCM commands the EGR valve to open and close 3 or 4 times in succession. As the EGR opens and closes. The PCM looks for vacuum changes in the line feeding the EGR. It uses the baro sensor on the firewall. Which is also hooked to the EGR control vacuum line, to sense the changes. If it does not see changes in vacuum. It lights the CEL.
Also I believe The PCM looks for small changes in the Boost sensor readings as the Valve cycles. In my truck I can see the PCM cycling the EGR in the boost gauge. It will go down and up a pound or two as the EGR cycles open and closed after I have been at cruise speed above 45 mph after a few minutes. If PCM sees EGR is not operating it throws the codes.
So The PCM is hard to fool because it uses redundant systems to check EGR operation. On OBD2 trucks like mine, they throw a MAF sensor in the mix. To sense changes in air flow . For further redundancy.
Best way to delete EGR is a performance tune with EGR delete. The performance tune will put a smile on your face:)
Just so you know. Deleting the EGR violates federal/ emission laws. So Joe Biden may come knocking at your door and tell you to. Get jabbed, put on your mask on, and hook up your EGR!

Getting the" F" lower intake to go along with the upper you have. Will help with air flow and power.
 

·
Registered
Joined
·
3,808 Posts
One other thing that can make your truck act like yours does. Check the gas cap. Make sure it is the proper vented cap for diesel engines and the internal vent is working. The fuel tank must be vented or vacuum builds and fuel cant be drawn thru by the lift pump.
 
1 - 3 of 3 Posts
Top