Cold Air Intake woes...

OP
OP
Avar928

Avar928

Well-Known Member
First Name
Michael
Joined
Dec 25, 2018
Messages
318
Reaction score
270
Location
DMV
Vehicle(s)
2018 JLU 2.0 Sport S Granite
Hey Michael,

This is odd and something I haven't heard of before. We ran all of our parts on our JL for several months and did a lot of highway driving and didn't have an issue. Do you know about what RPM you're running at when you feel like you're losing power?

To confirm that it is definitely the intake causing the issue, would you be willing to reinstall our intake and perform the same run? If there's any way you can log commanded vs actual boost, that would be super helpful too (not sure if that's even possible with this ECU right now).

I just went through a similar situation with my GTI (which uses a very similar turbo system as the JL, including the same diverter valve). Sometimes it would feel quick like it should, then sometimes in fourth gear it would fall flat on its face like it had no boost. I thought it was the DV+ I just installed, swapped back to stock DV, issue went away. As soon as I emailed GFB, the issue came back. Turns out my PCV valve was intermittently failing and causing the same symptoms as a bad DV.

All of that is to say that these engines do very strange things sometimes and it's tough to pinpoint issues. This really sounds like a high-load boost issue to me, but either way I'm happy to help any way I can.

-Steve
Thanks for the reply Steve. Yes, certainly would give it a shot and run through troubleshooting. She's on loan and is somewhere out Midwest with a friend so it'll be mid-August before I can re-install and document the problems. I definitely want to try and make it work.
Advertisement

 

Mishimoto

Well-Known Member
First Name
Mishi
Joined
Jul 5, 2018
Messages
357
Reaction score
419
Location
Wilmington, DE
Vehicle(s)
Jeep Wrangler JL
Thanks for the reply Steve. Yes, certainly would give it a shot and run through troubleshooting. She's on loan and is somewhere out Midwest with a friend so it'll be mid-August before I can re-install and document the problems. I definitely want to try and make it work.
No problem at all, I'll be here when it's back with you!

-Steve
 
OP
OP
Avar928

Avar928

Well-Known Member
First Name
Michael
Joined
Dec 25, 2018
Messages
318
Reaction score
270
Location
DMV
Vehicle(s)
2018 JLU 2.0 Sport S Granite
So a follow up I got my Jeep back and went ahead and reinstalled the CAI. First checked for any leaks in and around the IC pipe with some Windex and blipping the throttle a bit. None. Buttoned up the CAI and rechecked for any leaks and ran the gauntlet for a few days.

First day went well, performance appeared to be back to baseline. Not sure if it's me or anything but I do get a bit more lag when it's warming up from cold but it normalizes. The flatness feels like it's mostly gone under heavy load. I'm looking for consistency so will keep checking it on all ranges this coming week. I may swap back to stock for a day or so to get a re-feel of performance. Could have been a leak somewhere that's now sealed but who knows, I at least have some check points to look at if I feel it flatten again.

@Mishimoto Prior to buttoning it back up, I did notice some plastic flakes coming off from the oiled filter. Looks to be peeling from the seam line, I cleaned it with a rag and pulled off more flakes until it was all smooth. Made sure it was all gone before installing, something to note. I definitely didn't want that ingested at all.
 

Mishimoto

Well-Known Member
First Name
Mishi
Joined
Jul 5, 2018
Messages
357
Reaction score
419
Location
Wilmington, DE
Vehicle(s)
Jeep Wrangler JL
So a follow up I got my Jeep back and went ahead and reinstalled the CAI. First checked for any leaks in and around the IC pipe with some Windex and blipping the throttle a bit. None. Buttoned up the CAI and rechecked for any leaks and ran the gauntlet for a few days.

First day went well, performance appeared to be back to baseline. Not sure if it's me or anything but I do get a bit more lag when it's warming up from cold but it normalizes. The flatness feels like it's mostly gone under heavy load. I'm looking for consistency so will keep checking it on all ranges this coming week. I may swap back to stock for a day or so to get a re-feel of performance. Could have been a leak somewhere that's now sealed but who knows, I at least have some check points to look at if I feel it flatten again.

@Mishimoto Prior to buttoning it back up, I did notice some plastic flakes coming off from the oiled filter. Looks to be peeling from the seam line, I cleaned it with a rag and pulled off more flakes until it was all smooth. Made sure it was all gone before installing, something to note. I definitely didn't want that ingested at all.
Hey Michael,

To test for boost leaks, you'd really need to pressurize the system from the turbo - throttle at idle won't produce enough pressure to show anything without the engine being loaded. I usually use a coupler on the turbo inlet with a PVC cap and compressor fitting to pressurize the intake, just make sure you're not pressurizing any of the PCV ports in the wrong direction. Something like this usually works and you don't necessarily need the gauge if your compressor has one on it:
Boost-Test.png


But, I wouldn't go through the trouble if it's feeling normal now. And sorry to hear about the flaking on the filter. Could it have been rubber flashing from the molding process? There shouldn't be any plastic on the filter, so just wanted to make sure. Either way, I'll pass it on to the team to make sure QC knows to look out for it.

-Steve
 
OP
OP
Avar928

Avar928

Well-Known Member
First Name
Michael
Joined
Dec 25, 2018
Messages
318
Reaction score
270
Location
DMV
Vehicle(s)
2018 JLU 2.0 Sport S Granite
Hey Michael,

To test for boost leaks, you'd really need to pressurize the system from the turbo - throttle at idle won't produce enough pressure to show anything without the engine being loaded. I usually use a coupler on the turbo inlet with a PVC cap and compressor fitting to pressurize the intake, just make sure you're not pressurizing any of the PCV ports in the wrong direction. Something like this usually works and you don't necessarily need the gauge if your compressor has one on it:
Boost-Test.png


But, I wouldn't go through the trouble if it's feeling normal now. And sorry to hear about the flaking on the filter. Could it have been rubber flashing from the molding process? There shouldn't be any plastic on the filter, so just wanted to make sure. Either way, I'll pass it on to the team to make sure QC knows to look out for it.

-Steve
Hi Steve,

It was the flashing, definitely not on the filter!

Sounds like a good set up. I'll mock one up if I feel any drop-offs this week.

Michael
 

Mishimoto

Well-Known Member
First Name
Mishi
Joined
Jul 5, 2018
Messages
357
Reaction score
419
Location
Wilmington, DE
Vehicle(s)
Jeep Wrangler JL
Hey @Avar928,

Can't remember if I asked this already, but did you by chance change where you were getting fuel around the same time you put on the intake? Reading back over the thread, it could sound like a timing advance issue that I've felt with bad fuel before.

Thanks,
-Steve
 
OP
OP
Avar928

Avar928

Well-Known Member
First Name
Michael
Joined
Dec 25, 2018
Messages
318
Reaction score
270
Location
DMV
Vehicle(s)
2018 JLU 2.0 Sport S Granite
Hey @Avar928,

Can't remember if I asked this already, but did you by chance change where you were getting fuel around the same time you put on the intake? Reading back over the thread, it could sound like a timing advance issue that I've felt with bad fuel before.

Thanks,
-Steve
None that I recall, I gas up at either of two regular spots. When it was happening I switched over to stock on the same tank and it felt fine. I'm leaning towards it being a leak somewhere. So far so good I have been fairly consistent with performance this week (knock on wood). There has been about 1,700mi since initial install and removal and this install though. Not sure if that could have cleared whatever issue the initial install had but I'm hoping it stays the way it is now.
 

Mishimoto

Well-Known Member
First Name
Mishi
Joined
Jul 5, 2018
Messages
357
Reaction score
419
Location
Wilmington, DE
Vehicle(s)
Jeep Wrangler JL
None that I recall, I gas up at either of two regular spots. When it was happening I switched over to stock on the same tank and it felt fine. I'm leaning towards it being a leak somewhere. So far so good I have been fairly consistent with performance this week (knock on wood). There has been about 1,700mi since initial install and removal and this install though. Not sure if that could have cleared whatever issue the initial install had but I'm hoping it stays the way it is now.
Gotcha, just figured I'd throw it out there. Fingers crossed everything continues to perform well :fingerscrossed:

Thanks!
-Steve
 
Last edited:
Advertisement

TopLift Pros
 
Advertisement
Top