Car shuts off after JLT CAI and Kooks header leak maybe?

[Fuegooo]

I recently installed a JLT CAI and tuned my car for E85 with stock injectors. I've noticed that whenever i lightly tap the gas, the car would rev up to around 800-1200rpm and feel like its about to stall before returning back to normal idle rpm. Sometimes i can get it to turn off completely and the battery light comes on as if its in accessory mode. I had my tuner look at it and he says its reading similar to a vacuum leak but i couldn't find anything myself. The air/fuel ratio on my display is also capped at 10 for some reason but my car doesn't have a header or exhaust leak that I've noticed (Kooks LTH and Corsa Extreme). I already changed the MAF and i didn't notice anything different. On top of that, I notice sometimes the cars rpm would randomly fluctuate for a couple seconds at red lights before returning to normal.

Now moving on to the header leak, I installed them myself and had a shop double check to make sure there's no leak and all the bolts and tight. When i first installed it and got my e85 tune, the low typewriter knock i had actually went away. Soon after, a light knocking/tapping sound started coming from the engine bay. It's not something you can hear from sitting in the car or driving but it is noticeable whenever you go through the drive thru or an narrow alley where it echos a little. It completely goes away even in narrow alleys once its gets up to operating temp and is only audible by popping the hood. Like i stated earlier, the shop didn't notice any leaks so im hoping maybe a bolt just came loose from driving but i won't know for sure until i drop it off.

Hoping someone has experienced something similar to at least one of these things and are able to help out.

Thank you

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[tdstuart]

Pick up a smoke machine (there is some cheap ones online) and pressure test the intake system with it hooked up in the car.

I have had issues trying to find leaks and dealing with tuners and the simplest thing to do is to pull off the filter, rig up some way to shoot smoke through the cai and see if there is a leak. Tuner isn't there and will blame the intake/installation.

With the JLT intakes check the condition of the rubber gaskets that surround and hold in the vacuum line ports. Good luck!

 

[Swtbabybilly]

I 100% agree with @tdstuart it sounds like your getting un metered air into the system, if everything checks out good then id speak to your tuner, best of luck

 

[Fuegooo]

@tdstuart @Swtbabybilly thank you, im dropping the car off soon for a full inspection anyways so hopefully they have a answer for what the problem is or atleast if theres a lean or not

 

[Pistol_91]

The JLTs provided MAF curve is notorious for this type of behavior especially on e85. There's more to be desired from it and could be dialed in more tightly.

This is the exact reason I left Lund. On e85 my car would stall if I barely tapped the gas, or if I let the clutch out to move forward in a drive thru and pushed it back in. It would hesitate and die.

With literally nothing changed, I dialed in the MAF better and the issue went away, and never came back.

That's my experience with the JLT but you could have a very small vacuum leak. Id personally ditch the JLT and get a closed box intake. IATs are super high with open intakes.

 

[Fuegooo]

The JLTs provided MAF curve is notorious for this type of behavior especially on e85. There's more to be desired from it and could be dialed in more tightly.

This is the exact reason I left Lund. On e85 my car would stall if I barely tapped the gas, or if I let the clutch out to move forward in a drive thru and pushed it back in. It would hesitate and die.

With literally nothing changed, I dialed in the MAF better and the issue went away, and never came back.

That's my experience with the JLT but you could have a very small vacuum leak. Id personally ditch the JLT and get a closed box intake.

Thank you!

I should add that my car is automatic but i hope our problems are still closely related. If the air leak test comes back with nothing, i think that’ll be my next step.

 

[Fuegooo]

The JLTs provided MAF curve is notorious for this type of behavior especially on e85. There's more to be desired from it and could be dialed in more tightly.

This is the exact reason I left Lund. On e85 my car would stall if I barely tapped the gas, or if I let the clutch out to move forward in a drive thru and pushed it back in. It would hesitate and die.

With literally nothing changed, I dialed in the MAF better and the issue went away, and never came back.

That's my experience with the JLT but you could have a very small vacuum leak. Id personally ditch the JLT and get a closed box intake. IATs are super high with open intakes.

What is a Intake you might recommend? Any thoughts on Steeda, Corsa or Rotofab closed air boxes?

Thanks.

 

[ZachSteeda]

What is a Intake you might recommend? Any thoughts on Steeda, Corsa or Rotofab closed air boxes?

Thanks.

Steeda closed box FTW! https://www.steeda.com/steeda-555-3...intake?utm_source=7G&utm_campaign=zach-intake

 

[jcm3]

Not sure what tune you have, but occasionally when I go back and forth between my 91 tune and my E85 tune, I get similar results and have to reload it.

It will slowly rev to 1200 or so and is definitely off. A reload always fixes it, but not sure if this is what's happening to you.

Mods are similar to yours. JLT, E85 and long tubes, but I don't think the tune really changed much with the addition of headers.

 

[tj@steeda]

Some more feedback on our CAIs:

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