ISX 15L (cm2250) jake brake ?

**TimberTaxi** · 08.27.2012

Can anybody explain in detail why deleteing the Urea, DPF and EGR weakens the jake on the new ISX 15 (cm2250) ? Dose the DPF and EGR create that much more back presure in the exhaust or is it just something in the ECM that weakens the jake ?
Thanx TT

**Sportster2000** · 08.27.2012

It is a little bit of the DPF/back pressure, but I think that it has more to do with the VGT than anything. The VGT is what gives you that extra engine braking performance.

**TimberTaxi** · 08.28.2012

Thanks for the response. I'm not deleteing the VGT until it gives me troubles. But I am told I will still lose jake power just by doing the other deletes.
TT

**Heavyd** · 08.28.2012

The VGT is used to create additional exhaust back pressure to increasing engine loading and increase braking effectiveness. I don't get into deletes. I have no idea why the deletes would effect it unless the delete no longer uses the VGT through software changes.

**Sportster2000** · 08.28.2012

Everything that you listed in the original post, if you got rid of them, would not have an effect on the engine brakes. If you are losing engine braking performance it is because the "delete" tuner did something wrong. There I said it. Now I can be hounded by the people that make the deletes by telling them that they are doing something wrong.