Engine Light on 85HP Tune

[Shermanator]

I've done the "search" stuff on this issue but can't seem to find the answer, which no doubt is simple. On the 85 tune the engine light stays on, any problems with that? Dosen't do it in the tow tune......Sherm

[mikel]

No, it should not come on, but it is not a problem.

[tuningss]

Read the codes with the Predator and post them here.

[Shermanator]

P0231 and P0603. I changed the tune and went back to the tow tune, the P0231 dissapeared but the P0603 stayed but, the engine light was not on! The truck drove fine on the 85 tune but it really belched black smoke out when I nail it and then disappears once you let your foot out of it. Sherm

[Shermanator]

So I took the tune off the system and reloaded the original factory one. Then I went back and installed the tow tune and fired it up. The P0603 is still there but the "check engine" light does not come on. Truck runs great but is there something wrong with that code? Sherm

[Shag]

I'm having the same problem with my 2002 F-250 with 7.3 liter diesel. The only tune I've tried is the 85 hp one. REALLY woke the truck up but my check engine light stays on. I checked the diags and it indicated that the fuel pressure at the rails was too high? Something like that. It also aid that was normal for a tuned truck. I'd like to NOT have that check engine light on all of the time in case something else goes wrong. Is there a problem with the 85 hp Predator tune for this truck? Any fix available for this?

[Shermanator]

Shag, I posted another question under this topic and never got a definitive answer on it. I agree with you that if theres a problem with the 85 tune blowing up the pump or something else crapping out it'd be nice to know and get it fixed! I've been running the tow tune without any problem but the 85 does seem the way to go, if possible......Sherm

[jbeasts10]

Sounds like both of you may need to invest in a boost fooler.I would get codes all day long before I installed mine.Basically when you hit over 21 to 22lbs of boost the computer doesnt like it.I set my pressure relief valve to 20psi and my fuel pressure at 72lbs, the truck keeps diggin.No lights period,I have had it this way for over a year with NO issues.

[Shermanator]

OK, so whats a "boost fooler" and how much? Are those adjustments you speak of made on this device or elsewhere, thanks..Sherm

[jbeasts10]

A boost fooler is nothing more than a air pressure regulator.It mounts in-line between your turbo and Map sensor . You can buy them as a kit,I made mine from an Air Pressure Regulator I bought at Lowes.If you do decide to make one yourself,you will need to pre-set the air pressure to right at 20psi(bench top test).This will allow the Map sensor to see No more than the allowed amount of Air pressure.Some have said that the Computer will actually cause the truck to De-Fuel if the Map sensor sees more than 22psi,Mine has Never de-fueled,merely thrown a code.
As for the fuel pressure adjustment,I installed the ITP Regulated Return Fuel System.This allows you to adjust your fuel pressure and removes the Dead-Head on Cylinder #8(Basically a Air pocket) in the fuel system.Shoot me an IM if you have anymore questions.I hope this sheds a lil more light on the subject.

[okiestroker]

Having same issue with 85 hp tune..has anyone had success with the mods jbeast10 mentioned..any issue of creating back pressure on the turbo by installing the air regulator?..what did you set the fuel pressure at after installing the ITP??....Thanks for all the insight.. been runnin the tow tune till could do some research here.. great info

[jbeasts10]

Having same issue with 85 hp tune..has anyone had success with the mods jbeast10 mentioned..any issue of creating back pressure on the turbo by installing the air regulator?..what did you set the fuel pressure at after installing the ITP??....Thanks for all the insight.. been runnin the tow tune till could do some research here.. great info

It doesnt create any back-pressure on the turbo,it bleeds it off before the map sensor reads it.Initial fuel pressure was 65psi...since playing around with the Regulated Return I have found for my set-up 72psi seems to perform the best.