Odd 2.4 rattle only under load while moving

Guitarguy

TJ Enthusiast
Joined
Sep 21, 2019
Messages
126
Location
Kansas City
Hey guys! So I've got a 2006 Wrangler 2.4 with a 6 speed. For awhile now, it's had a weird rattle sound from between 2000 and 3000 rpm. It's slowly gotten worse over the last month or so and I'm doing my darndest to figure it out but the kicker is it only does it under load when it's moving! It gets much better as it warms up too. By the time it's warmed up to around 190-200, the rattle is very faint and it only happens between 2k and 3k rpm and only when I try to accelerate, not when I coast at the same rpm. I do have a whirling idler pulley and a check engine light for a very small evap leak but surly that's not it right? What do y'all think? Any help would be greatly appreciated. Thank you.
 
Everyone describes noises differently. What I call shrieking harpy screeches, my wife calls polite subtle requests. What you call a rattle others may call a knock. You could be hearing valve lifter noise or God forbid bottom end noise. Who knows? Could be a multitude of non-issues as well. Can you upload a recording? Understand, it is better to have a competent person looking at it first hand rather than trusting an upload that may have a noise in it, but the recording will not be easy identify the source location. Exhaust leaks can be deceptive and injectors can click as well.
 
Good point. I'll upload a video either when I get off work or on my way to work tomorrow. I'm really hoping it's that idler pulley 😂. I'll replace that tonight and see if that solves it.
 
I had to pull the heat shield off of the exhaust on my 06 2.4 it was rattling like crazy. The one under the hood above the cat.
 
I ripped that heat shield off when I tried to change the oil pressure sensor hahaha also here's the video. I haven't seen it yet so I hope the rattling comes through.
 
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I ripped that heat shield off when I tried to change the oil pressure sensor hahaha also here's the video. I haven't seen it yet so I hope the rattling comes through.
That's exactly when I ripped mine off, the oil pressure sender would randomly fail causing my gauge to zero and dash warning to beep, I got rid of two annoying sounds at once.
 
Hey guys! So I've got a 2006 Wrangler 2.4 with a 6 speed. For awhile now, it's had a weird rattle sound from between 2000 and 3000 rpm. It's slowly gotten worse over the last month or so and I'm doing my darndest to figure it out but the kicker is it only does it under load when it's moving! It gets much better as it warms up too. By the time it's warmed up to around 190-200, the rattle is very faint and it only happens between 2k and 3k rpm and only when I try to accelerate, not when I coast at the same rpm. I do have a whirling idler pulley and a check engine light for a very small evap leak but surly that's not it right? What do y'all think? Any help would be greatly appreciated. Thank you.
 
Sorry it's not letting me upload anything for an audio file or a video. It got a lot worse today with the cold though and that idler pulley wasn't it.
 
It's a diagnostic tool that plugs into your OBD port and reports to your phone. The bluetooth OBD plug cost around $10bucks and the Torque pro software is another $10.
ELM327 adapters are available on Amazon, Ebay or Autozone. The Torque Pro software is available at the Google play store on your phone, tablet or computer.
20200117_000241.jpg


The program looks like this on your phone you can watch various sendors in real time like timing advance, to rule out detonation.
Screenshot_20191006-192031_Torque.jpg

There is also various driving tests you can run including a detonation test.
 
Oh wow yeah I'll definitely check into that!!!
It's a great tool to have, I have a spare tablet I use as a separate gauge cluster in Torque pro when I'm towing to watch things like transmission temperature, fuel consumption and other important stuff when stressing out the vehicle. Plus its very helpful in fixing intermittent problems like vacuum leaks that can trigger engine lights which it can ckear as well.
 
Hey guys! So I've got a 2006 Wrangler 2.4 with a 6 speed. For awhile now, it's had a weird rattle sound from between 2000 and 3000 rpm. It's slowly gotten worse over the last month or so and I'm doing my darndest to figure it out but the kicker is it only does it under load when it's moving! It gets much better as it warms up too. By the time it's warmed up to around 190-200, the rattle is very faint and it only happens between 2k and 3k rpm and only when I try to accelerate, not when I coast at the same rpm. I do have a whirling idler pulley and a check engine light for a very small evap leak but surly that's not it right? What do y'all think? Any help would be greatly appreciated. Thank you.
Man i had an 03 with a 2.4 and i regretted it badly. The engine was knocking horribly under a load especially. Always changed oil and ran full synthetic from day one. The jeep only had 29k miles on it and was still under warranty. However, they told me that cuz i had a 2.5" lift and 34's that it voided my warranty. Thet wouldnt fix it so, i told em to come get it. They never did so i parted it out. Lol. Screwed my credit but its ok now. Lol
 
Dang! Mine has 120,000 on it now. No lift but when I got it, it had 31x10.5 tires with centerline rims. It didnt do the rattling thing but wow was it slow. I bought some stock rims and tires and now it's drivable again! It wasn't for a few thousand miles later that it started rattling. I definitely agree though after doing a valve cover gasket, timing belt, and oil pressure sensor, it's definitely not as well built as the 4.0. It is pretty great on gas though!
 
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There's a huge restriction in the exhaust hidden above the transmission skid plate. Once I removed that and put a 4.0 airbox on mine I gained 20hp at 4800rpm went from 101hp at the wheels to 121hp. I really like the 2.4, its so much faster than the 2.5 and way lighter than the 4.0. It goes great offroad as long as your not afraid to rev it. It does suck on the highway compared to the 4.0 though. Once I do the cams and add a turbo its gping to be fun. I run 31x10.5s also
 
My other tj is a 2.5 and i def love it more than my 2.4. Once i added some gearing to it, it was apot more peppy. Im able to run 34's and be right back to where it was stock. The availability for parts and the more simple design makes it alot easier to work on if broke on the trail. The low end torque is much better it seems on my 2.5 as well. Learned the hard way that revving alot of rpm's off road with stock axles, dont work out too well with any motor. Lol. First the ring and pinion goes and then after gearing it, ya start popping axles. My opinion is to gear em low and crawl through whatever. Hopefully nobody buys a jeep to go "fast".
 
My other tj is a 2.5 and i def love it more than my 2.4. Once i added some gearing to it, it was apot more peppy. Im able to run 34's and be right back to where it was stock. The availability for parts and the more simple design makes it alot easier to work on if broke on the trail. The low end torque is much better it seems on my 2.5 as well. Learned the hard way that revving alot of rpm's off road with stock axles, dont work out too well with any motor. Lol. First the ring and pinion goes and then after gearing it, ya start popping axles. My opinion is to gear em low and crawl through whatever. Hopefully nobody buys a jeep to go "fast".
I don't know if you realize this but the twin cam 2.4 Chrysler engine produces more low end torque than the 2.5 as well as much more top end. Chrysler as well as Mitsubishi has built millions of these motors begining in the late 70s many of them turbo charged so there are tons of parts available new and used in junkyard vehicles. In the 90s Chrysler along with Lamborghini redisigned the heads resulting in the Turbo SRT motor Shelby routinely got 300 reliable horsepower from these motors. My 2.4 TJ came stock with 4.10 gears and a 6spd stick shift, I have no intention of going bigger than 31x10.5 tires and with only 120 wheel horsepower I have no fear of breaking ring and pinions. At 88k miles mine is still going strong and has been relatively maintenance free.
The newer 2.4 World engine that came out in 07 is another story. That motor is built by the Global Manufacturing Alliance in their factory and is a giant POS it shares zero parts with the Chrysler/Mitsubishi motor.
 
Hey guys sorry it took so long to get this posted but I finally had a second to get this video up. I hope it comes through on the audio. Sorry for my goofy sounding voice, I'm getting over a bit of a cold.