Intake air heater
 

Delete or not?Does it actually help?It seems awfully restrictive if you ask me.Every little thing counts to make these animals breath so I would think it to be a good thing.

Well, I deleted mine about a year ago. All I can really say is that I haven't had any negative side-effects. It makes for a great spot to plug in your boost pressure gauge sensor if you get an AIH delete plug that is tapped for it.

It's your call on whether or not you want to take it out. It's not hurting anything by being there, but it's not doing much of anything anyway.

It only turns on when ambient air temperatures are below a certain temperature and the engine is idling for a specific amount of time.

If you delete the heater, be sure to leave the relay and wiring in place (it's easy to tape up and stuff the red power wire into the engine valley) so that you don't get any codes. If you delete the relay and wiring, you WILL get a code that will fail your emissions test if you currently have testing in your area. Depending on the truck, it can turn on the check engine light if the relay and associated wiring is disconnected.

Good point Cody. I do get a soft code from deleting the AIH, but it doesn't set any lights. The only detrimental effect I have seen is that I was unable to run a cylinder contribution test because of the code (which I couldn't clear because the AIH and wiring is gone).

Good point, Bob. I forgot about that.

It just appears to be restricting the air flow with such a large heater sticking thru the center like that,but if it isn;t going to gain anything why would you remove it.

It may affect airflow to a small degree. I got rid of the one on my '01, but at 310 RWHP, I wasn't leaving any performance on the table with it installed or not. I just put a boost gauge fitting in the hole and called it good.

For a almost free mod I would pull it, it is not helping anything. It might not be a big improvement but it will help.

heater
 

I have often wondered if it could be wired to come on during the glow plug warm up to help warm air for a cold start. Isn't that all the cummins has for cold starts. Has anyone wired it that way?