Hello everyone, a while back I installed a bd boost fooler along with a set of RV275 injectors. I installed a boost gauge before this just to see the difference, if any before and after this was done. My truck would build 24ish pounds on a hard pull, same with a trailer behind it. No change in boost after injectors or fooler. I had my scanner hooked up yesterday playing around and noticed my ECM was seeing 14lbs at idle, and when my truck was actually making 20lbs the ECM would show 34lbs. Shouldn't that be setting an overboost code? Was just curious if this was normal with the foolers?

some of that would depend on your scanner. I have a scan gauge II that shows 29 psi at idle and 32 at WOT. As far as more boost you will need a boost elbow to delay opening of the waste gate to make more boost. It bleeds pressure off of the waste gate so it opens later. The boost fooler takes care of the electronics but the waste gate is mechanical.

The 14 psi at idle is atmospheric pressure where a dash mounted gauge will show 0 psi.  When I put my code reader in live data mode it shows the atmospheric pressure also at key on engine not running where the dash gauge reads 0.  The ECM has to take into account the loss of pressure as the truck goes up in altitude so that it can decrease the fuel for a better burn.  So what you are seeing is normal.

No scan tool can read the MAP sensor correctly. Mine reports 28.3 at 2,800 feet for 2001 MAP sensor. Mine will max out at 37.3 PSI

 

 

Thanks to everyone for the replies, I have a Snap On Modus as my scanner. The truck was an automatic when i got it, I swapped a 5 speed in but still have the HY35 with the wastegate J-Hooked shut. 

Edited October 30, 20195 yr by OldSmokey