Failsafe engine mode

[5.0 guy]

I had to drive almost 1,000 miles round trip to Colorado springs and back to get dyno tuned. The car ran great but when I returned last night I ran it down the street and now the "failsafe engine mode" shows up on the dash. Anyone had this problem? it seems like the Mass air has a howl so I'm wondering if the meter is bad or the tps went out, everything is new as for the car only has 431 miles on the clock. Anyway's, dyno numbers with a stage3 are as follows.
20% humidity at about 5,000ft
Superflow 525RWH 536 RWT
Dynojet 565RWH 577RWT
This car still has the factory exhaust on board and the car was extremely hot after 5 hours of tuning.I was happy to get a reading of what the car does on the street when hot and not right off the trailer!:burnout:

 

[skyhighsd]

I had some issues with it when I installed my KB. It ended up being a issue with my inlet tube on the cai I didnt have it all of the way around the TB on the bottom side. After you find a problem take a lead off of the battery for 15-20 mins and replace and you should be fine. Make sure you have no issues with you CAI all of the clamps are good that is some place to start.

 

[Shaker1]

Yeah, sounds like either unmetered air or a vacuum leak/loose connection. Particularly, since you drove it all the way back after an extended dyno session with no problems until now.

You have the tuner that came with the stage 3? Try and pull codes.

Also, if you replaced the plugs, maybe one has worked loose.

 

[5.0 guy]

I ageree with both of you as far as it being something simple to do with air. I didn't drive her home, she was trailered and it didn't start howling or have speratic idle until I rolled her off the trailer. Ford did a check for me and they showed the Idle air controler haveing a failier. We went to order one and they do not sell it sepperately so I ordered another complete throttle body. I changed it out today and it runs the same and has the howl around the airfilter. It acts as if it has a vaccume leak or something. I did however change out the throttle position sensor since I had a new one on the new throttle body. I also dissconnected the battery and it still runs funky. On another note I did notice at some point someone over cranked both ends of the carbon fiber peice of the JLT and thought that may be my problem as for both sides are split. I changed back to the stock system and the howl was still their so I'm lost at this point!:bash: It spits and jerks at low speeds so I'm wondering if it could be a bad plug.

 

[Shaker1]

If the JLT is split that is going to be a problem eventually, even if it is not the current problem. Contact Jay Tucker @ JLT about ordering a new one.

I think you would be better off (temporarily) using the stock air tube with the JLT MAF housing, rather than putting on the complete old system with the new tune. But, even though this may affect your tune, probably not to the degree you are presently experiencing.

Also, since (I believe) the Stage III comes with a 160mm Mono Blade Throttle Body, and you have proven that the new (Ford OEM) thottle body has not resolved your problem, you should probably re-install the Stage III TB. Cuz it will affect your tune too.

If you are still getting IAC error codes then check the wiring harness to IAC and look at the connector/wiring for any possible damage.

Check that the harness connection to the MAF is OK and that the screws where it is mounted to the housing were not over tightened, thus bending the tabs and creating an air leak.

Check all vacuum lines that are in the vicinity of the CAI and throttle body. Both ends.

If you take off the coil covers you can check your coils and verify you do not have a loose plug. If possible use a torque wrench to re-install the plugs so you do not strip the threads. Aluminum heads, ya know.

Sometimes people spray things like carb cleaner or propane around the intake area to try and find a leak. When it gets sucked in it will change the idle. I don't need to tell you be careful, very flammable. You can also use a stethoscope or piece of tubing to listen for a "whistle", signifying an air leak.

One more idea. Sometimes an over oiled filter can get oil on the MAF sensor and throw off the reading. You might try using some electrical contact cleaner to clean the MAF wire. Remove the MAF sensor to do this. Better not try touching the wire with anything. If no contact cleaner, some carb cleaner usually works.

 

[5.0 guy]

Excellent ideas! I didn't change out th TB to stock,just the CAI and it didn't change anything.The factory tube won't fit the JLT meter so I reinstalled the complete JLT since it's tuned for it. There is definately an air leak somewhere, but I think you're right on with the plugs. I'm thinking that's why it spits at low rpm driving. thanks for your help, I'll try this stuff out and let you know the outcome.

 

[Shaker1]

OK, I see. You ordered the TB and used the IAC from it as a replacement. In that case, be sure and check the ST III TB is not leaking where it meets the intake manifold.

 

[5.0 guy]

It looked all clean when I removed it, yes you are correct, I had to buy the stockTB and then stripped it for parts! We are on the same page in what to look for, I'll keep you posted when I look further!!

 

[que4dog]

What was the outcome?

 

[91svtbird]

I ageree with both of you as far as it being something simple to do with air. I didn't drive her home, she was trailered and it didn't start howling or have speratic idle until I rolled her off the trailer. Ford did a check for me and they showed the Idle air controler haveing a failier. We went to order one and they do not sell it sepperately so I ordered another complete throttle body. I changed it out today and it runs the same and has the howl around the airfilter. It acts as if it has a vaccume leak or something. I did however change out the throttle position sensor since I had a new one on the new throttle body. I also dissconnected the battery and it still runs funky. On another note I did notice at some point someone over cranked both ends of the carbon fiber peice of the JLT and thought that may be my problem as for both sides are split. I changed back to the stock system and the howl was still their so I'm lost at this point!:bash: It spits and jerks at low speeds so I'm wondering if it could be a bad plug.

If the JLT is split that is going to be a problem eventually, even if it is not the current problem. Contact Jay Tucker @ JLT about ordering a new one.

I think you would be better off (temporarily) using the stock air tube with the JLT MAF housing, rather than putting on the complete old system with the new tune. But, even though this may affect your tune, probably not to the degree you are presently experiencing.

Also, since (I believe) the Stage III comes with a 160mm Mono Blade Throttle Body, and you have proven that the new (Ford OEM) thottle body has not resolved your problem, you should probably re-install the Stage III TB. Cuz it will affect your tune too.

If you are still getting IAC error codes then check the wiring harness to IAC and look at the connector/wiring for any possible damage.
Check that the harness connection to the MAF is OK and that the screws where it is mounted to the housing were not over tightened, thus bending the tabs and creating an air leak.

Check all vacuum lines that are in the vicinity of the CAI and throttle body. Both ends.

If you take off the coil covers you can check your coils and verify you do not have a loose plug. If possible use a torque wrench to re-install the plugs so you do not strip the threads. Aluminum heads, ya know.

Sometimes people spray things like carb cleaner or propane around the intake area to try and find a leak. When it gets sucked in it will change the idle. I don't need to tell you be careful, very flammable. You can also use a stethoscope or piece of tubing to listen for a "whistle", signifying an air leak.

One more idea. Sometimes an over oiled filter can get oil on the MAF sensor and throw off the reading. You might try using some electrical contact cleaner to clean the MAF wire. Remove the MAF sensor to do this. Better not try touching the wire with anything. If no contact cleaner, some carb cleaner usually works.

FYI---The GT500 does not have an IAC (idle air controler) at all.

The idle is controlled completly by the ETC (electronic throttle body)

All the other suggestions on checking for inlet air leakage are very good though.:beer: