Advice for Dealing with Stuck IMRC's

Dominus

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I popped a CEL earlier this week that turned out to be code P1518 (stuck open IMRC's) and began the usual liberal usage of SeafOam and CRC intake cleaner. After doing this a few times and achieving nothing, I decided to just reach my hand back there and twist them manually. Sure enough, it was stuck hard and came free. Don't be shy. Just torque it good with your fingers and work it back and forth.

After I did this, I erased the code and took the car out for a few good revs. Sure enough, no more codes. But it needed physical intervention.

I guess my first indication that I had that problem was that the exhaust coming from the left side pipe was distinctly different from the right side. The passenger side IMRC was the one that was stuck open.
 
Check your vacuum lines and Seafoam it. If that doesn't work, you have some disassembling to do...
 
Dominus said:
I popped a CEL earlier this week that turned out to be code P1518 (stuck open IMRC's) and began the usual liberal usage of SeafOam and CRC intake cleaner. After doing this a few times and achieving nothing, I decided to just reach my hand back there and twist them manually. Sure enough, it was stuck hard and came free. Don't be shy. Just torque it good with your fingers and work it back and forth.

After I did this, I erased the code and took the car out for a few good revs. Sure enough, no more codes. But it needed physical intervention.

I guess my first indication that I had that problem was that the exhaust coming from the left side pipe was distinctly different from the right side. The passenger side IMRC was the one that was stuck open.
How did you get to the IMRC. My code is P1519. Did you just take of the intake tube and do it from there? could explain the process
 
Sorry, what I meant was you reach your hand to the back of the manifold, where the IMRC shafts actually are, as well as the connectors to the actuator. Twist those shafts with your fingers back and forth.

I don't know how it is on the Gen1, but ont he Gen 2, you can just follow the IMRC cables to the shafts at the back of the engine and twist them. Worked like a charm.
 
so you don't have to open up anything, right? You just reach behind the Manifold, and there would be shafts....
 
You think you can point me to where the shafts are by these pics

DSC09353.JPG


DSC09354.JPG


DSC09355.JPG
 
It's hard to see in your pictures. I'm going to take my own right in just a minute so you can see, but basically all you need to do is to follow the actuators cables coming from the IMRC control box to the levers on the ends of the shafts, and then just manipulate them with your fingers. Gets them free real quick.

Your P1519 means you have the driver's side IMRC set stuck closed. This side is more difficult than the passenger side, but not impossible.
 
thats your fuel rail........on your first pic, the black cable i marked goes to the pass side imrc, follow it back to find the little bracket were youll find both cables then follow the other one to the drivers side imrc, youll feel the bare cable just pull on it to open up the imrc's

imrccablethingy.JPG
 
Ok so you pull on it to open the IMRC. So mine are stuck closed so I should push it out. I first did the Passenger side, and it opens and closes but the wire isn't attached to anything. is this how its suppose to be?
An then I tried to get the driver side but I can't grab it. I can touch it but can't seem to grab it. is there a tool that can be used to get the wire?
 
Sorry I was away for a bit. You can reach the driver's side IMRC shaft, but it is just a huge pain to get at. You have to really shove your hand in there.

Those cables pull on levers attached to the shaft ends. You need to grab that lever and move it back and forth if you can.
 
srry to get off topic... but what is that round thing sitting on top of the engine. ive always looked at it and never could tell what it was..
 
What do IMRCs do, and what are some symptoms of them gone bad?
Thanks.
 
Your engine has 16 intake ports. The IMRC's open and close 8 of those 16 ports. When those 8 ports are closed, the velocity of the air going into the other 8 intake ports greatly increases compared to when all 16 are open. The result is better cylinder filling at lower rpms, which of course means better low end power and torque.

At 3500 rpm, those other 8 ports are opened up by the IMRC shafts and all 16 ports receive air. At those engine speeds, greater airflow is achieved with all 16 ports open giving greater top end power than a typical 2 valve per cylinder engine.
 
Well, besides shooting a check engine light, if you live in a place where it gets cold you can visibly see the difference between the exhaust on the driver and passenger sides. That was the most profound indicator to me. I have an LSC though, which has a dual-like exhaust (not true dual though).
 
turborich said:
How would you know if they are stuck? any obvious signs?



Lack of high rpm pull if they are stuck closed. Lackof low rpm pull if they are stuck open.

My expierence anyway.


Mike
 
please delete I updated this below and wasn't able to delete this post. Thanks.
 
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so you don't have to open up anything, right? You just reach behind the Manifold, and there would be shafts....

To me they are more like levers. Each IMRC has a lever, a cable and a return spring. The spring can get stuck without any maintenance.

I think these should be a regular maintenance item. Once a year or more depending on your climate. (moderator what do you think?)

I reached in and mine was stuck and it felt pretty solid. As Dominus says don't be shy. (Thanks Dominus!) With a bit of effort it moved but stayed in the closed position (meaning it didn't want to move back) at first anyway. A few more times moving the lever back and forth and it loosened right up. Then some silicon spray and she was fine.

This happened after she sat for two weeks. Fine when parked and the P1518 code within the first drive. Although she drove almost normal. Only thing I noticed was a tiny shake when starting cold for a few seconds.

I took some pics from the passenger side IMRC. The driver side is harder to get to and see, but was still able to spay some lubricant on the spring.

20141220_170955- Closed position.jpg

20141220_170808- Stuck open position.jpg

20141220_170955- Closed position.jpg


20141220_170808- Stuck open position.jpg
 
Hey, 91, thank you very much. I don't care if you answered a 9 year old post - it sure helped clear some things up for me. Thanks again. DaveP
 
Hey, 91, thank you very much. I don't care if you answered a 9 year old post - it sure helped clear some things up for me. Thanks again. DaveP

Happy to help! Many here have helped me and I'm glad to return the favour.

This should be on the preventive maintenance list, something so easy - a spray or two of oil every few months to keep the IMRC levers/spring moving smoothly.
 
Happy to help! Many here have helped me and I'm glad to return the favour.

This should be on the preventive maintenance list, something so easy - a spray or two of oil every few months to keep the IMRC levers/spring moving smoothly.

I should have taken my own advice. Same code two years later and the IMRC was stuck again. This is an easy fix, still I highly recommend putting a spray lubricant on the left/right spring/lever each time you change your oil.

What do you guys find works best? Wheel bearing grease? I used Rust check last time and it lasted two years, it is a great penetrating oil and stops rust, but I find it is a dirt magnet. This time I tried a silicone spay lubricant. I think it would not be easy to get high temp bearing grease to the driver side IMRC spring/level.
 
I should have taken my own advice. Same code two years later and the IMRC was stuck again. This is an easy fix, still I highly recommend putting a spray lubricant on the left/right spring/lever each time you change your oil.

What do you guys find works best? Wheel bearing grease? I used Rust check last time and it lasted two years, it is a great penetrating oil and stops rust, but I find it is a dirt magnet. This time I tried a silicone spay lubricant. I think it would not be easy to get high temp bearing grease to the driver side IMRC spring/level.
I have a spray can of white lithium grease that would likely stick to the imrc levers. I do not know as I have not tried it but it sould like the best way to apply it.
 

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