Is it worth changing this out if bad? Does this help on cold starts that much? We have a few trucks that are kinda hard to start when cold. I reacently repalced the GPR's last year on them. So we know they are ok. And how would a guy check to see if they are bad at all? Thanks abunch AGAIN

Does any body know what the part number for this is? Is it just a reg relay?

 

The air intake heater doesn't do anything on startups. I have seen a couple good explanations of the AIH on here, but I can't find one at the moment.

 

^^^This is correct. The AIH does not affect start up in any way. It only comes on after the engine is up and running and usually after the glow plugs have cycled off. It's purpose it to minimize excess smoke in cooler ambient temps while idling a cold engine. It really could quality as a sort of emission control item since that is what it's function really is.

 

Found it.

FAQ: What is the real purpose of the intake heater, and when does Ford say it will operate normally?
"To reduce white smoke during long idle periods at low ambient temperatures, the PCM will activate the intake air heater. Specific conditions must be present before the heater is activated: "
• ambient temperature must be below 0 deg C (32 deg F)
• engine oil temperature must be below 55 deg C (131 deg F)
• vehicle power must be between 11.8 and 15 volts
• parking brake must be applied on manual transmission vehicles
• the transmission must be on park or neutral on automatic transmission vehicles
• glow plugs must be off

I think this is actually from Rifraff's web site. It has been quoted on these forums often.

 

Ok. THANK YOU SO MUCH!!!!

 

As far as I know it is the same as the Glow Plug Relay and same part number. 25.00 At NAPA when asked for under part number GPR109.

As with the specs stated above it is most likely not to come on very often. If your GPR goes out and you need the relay I think that you can move this one over to it (GPR) until you get it replaced.

 

Lots of folks just delete the AIH altogether. Use the leftover port for a boost gauge or just plug it. We deleted the AIH's from our trucks but left the relays in place as "ready to go GPR spares"

Thinking of Trying an exp on one of ours - use the orig GPR to power the GP's on the left and the old AIH relay to power the right side GP's. Hook up the signal lines from the PCM to a small switching relay and then put the "dual GPR's" in parallel so both come on @ the same time. Figure 1/2 the current should increase the relay life. Haven't done it yet but we've mapped it out on an 02 F350 SRW that seems to eat GPR's. (Mainly cause this one gets a lot of starts)

 

Nice!!! Will keep that in mind!

 

are the part numbers the same for the glow plug relay and the air intake relay?

 

Yes, at Napa GPR109