Question about JLT Cold Air Intake

I'm pretty new to Mustangs and modding cars in general. I recently bought a JLT CAI, 3.73 gears, and a tune for my 12 Mustang GT. I had the tune set for the 3.73 gears, which will be installed Monday and I was thinking about installing the CAI tomorrow. My question is will my car still run with the JLT CAI if I wait to put the tune on until the gears are installed? Since the tune is set for 3.73 gears do I have to wait until the gears are installed to put the tune on? Sorry if this is a dumb question but I'd rather ask then take the risk of messing up the car! Thanks- Matt

No, the JLT has a different sized MAF and you need to let the car know it's there.
It will run like crap or not at all.

fdjizm said:

No, the JLT has a different sized MAF and you need to let the car know it's there.
It will run like crap or not at all.

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It'll just run like complete crap. You can throw the tune on and install it. Your speedometer will be off until you install the tune.

You should be able to change the gear ratio with your sct.

zinc02gt said:

It'll just run like complete crap. You can throw the tune on and install it. Your speedometer will be off until you install the tune.

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So it won't hurt the car at all to install the CAI and the tune before I actually have the 3.73's on the car? If so this is probably what I'll end up doing. Thanks

Matt you can load the tune and adjust the gear ratio with the sct.

Ok thanks, sorry for some reason I didn't see your 1st post when I replied to his.

You can install the CAI. But it will idle like shit or wont idle at all. Will probably take 10 times trying to get it to idle. Once it does let it idle and give the o2's a chance to learn and it will run eventually it will run with no problems.

But you might as well just load the tune and change the gear setting and just reload the tune when the 3.73 is installed.

Here's the deal.... Matt ordered his tune from American Muscle for a JLT and 3.73 gears. He installed the JLT and loaded the tune, after about two driving cycles he has a CEL. His gears get installed tomorrow, my question is can not having 3.73s installed cuase a CEL? I told him to recheck the install (leaks) on the CAI and if that is good to reload the tune. Any help? Am I missing something?

Use the sct to pull the code and report back, as far as the gears go again you can enter in the stock gears into the sct and load the tune. It's really not as hard as yall are making it out to be.

jewc75 said:

Use the sct to pull the code and report back, as far as the gears go again you can enter in the stock gears into the sct and load the tune. It's really not as hard as yall are making it out to be.

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I'll have him pull the codes and post them..... I know changing the gear ratio on the SCT is not a difficult task however, I would have never thought it would turn the CEL on.... Speedo off yes but would that turn the CEL on?

No cel for gears. Tell him to reset the codes and restart the car.

Codes are P0171 and P0174 both are lean codes I believe.... He has cleared the codes and if they come I told him to call Bamma in the am to verify corect tune was sent.....

call Bama directly at 888.226.9764

Bama guys are great ppl. They will do anything for the costumers. Give them a call and they WILL straighten you out.

Kingcrabb said:

Bama guys are great ppl. They will do anything for the costumers. Give them a call and they WILL straighten you out.

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I bet they are, and I know they will make it right..... Matt give them a call tomorrow even if your CEL does not come back on just to verify you have the correct tune.

TheRookie65 said:

Here's the deal.... Matt ordered his tune from American Muscle for a JLT and 3.73 gears. He installed the JLT and loaded the tune, after about two driving cycles he has a CEL. His gears get installed tomorrow, my question is can not having 3.73s installed cuase a CEL? I told him to recheck the install (leaks) on the CAI and if that is good to reload the tune. Any help? Am I missing something?

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Did he forget to hook the sound tube back on or plug the hole on the cai for the sound tube? That will give him a lean code.

Rob72 said:

Did he forget to hook the sound tube back on or plug the hole on the cai for the sound tube? That will give him a lean code.

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Rob thanks, I wil have him check that as he did have a problem installing the tube......

Remind him that any loose connection or opening after the MAF sensor will cause the engine to run lean.

Thanks for your help everyone. I'll be checking all the hoses and clamps first thing in the morning and then calling Bama to make sure everything is good to go before I have the gears installed.

in for an update......