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Abneriel
10-29-2004, 09:18 PM
...figured I should probably get off my butt and clean them since I'm sure it wouldn't hurt...

How hard is the task? I've replaced the front calipers/rotors, changed oil , installed electronics (ie speedcal, stereo), etc...how much harder is tackling the IMRCs? Are there any diagrams or instructions on how to get to and clean them? Will I need to buy any new gaskets or anything?

If there aren't any diagrams...would anyone mind posting directions? Any pictures would help...

Thanks

Firme
10-30-2004, 03:26 AM
You are in luck my friend. The South Central Region of SCMC has a Tech write-up on cleaning the IMRC's

here you go..

http://www.svtmustangcobraclub.com/media/pdfs/tech/IMRC_Cleaning.pdf

Abneriel
10-30-2004, 10:31 PM
thanks!!! should make it much easier... :)

overkill91
10-31-2004, 11:25 PM
How often should you do this?

SNAKEYE
11-01-2004, 03:19 PM
How often should you do this?
I just did mine at 43k miles, and would recommend that you NOT DO THEM as some kind of routine maintenance thing, but only when you know they are not working properly, or have ceased to function. It took me about 6 man-hours. Except for assistance to lift the lower intake back into place during re-assembly (the tricky part of the job with wires and fuel rails grabbing at the intake as it was set back inplace), I did the teardown, cleaning, and reinstall myself.
Mine had ceased to function as evidenced by the loss of the kick in the butt under 6 psi of boost.
Prior to a visual inspection I had reached down to the levers at the back of each IMRC with a hooked piece of coathanger wire and was able to manually operate the linkage without difficulty. So I was prepared to have to do an IMRC module replacement.
Sure enough, after tearing the intake manifold off I really didn't have any substantial buildup of carbon and varnish as some have shown in various articles. This kind of substantiated my earlier ability to move the linkage manually.
With no apparent method to test the original module I simply opted to but in a new one and have it over with. With a friend in the local Ford dealer's parts department I got away with the required parts: (2) O-rings for the coolant tube, and the module, for around $100. It took (7) cans of carb cleaner,a couple of rolls of paper towels, and countless latex gloves (that carb cleaner will ruin your skin!). All of the gaskets are reusable.
The articles I read and used as reference during the cleaning process were detailed enough to have a successful cleanup effort. You might wish to research bolt torque values and sequences so that you don't overdue torques during re-assembly. They are low values, in the range of 70 to 180 IN-LBS! An IN-LBS torque wrench was really handy.
Upon initial startup the engine was really sloppy. It didn't want to idle until it reached normal operating temperature. I just kept it going with my foot until it smoothed out - maybe 10 minutes. That was an anxious time!
Performance since is right back to its old head-snapping, tire-blistering self.

overkill91
11-03-2004, 09:10 PM
I wish i could compare mine to something but i just bought it with 50k on the od. I guess ill look harder for the kick at 3k but cant say that there is any night and day difference at that rpm.

SNAKEYE
11-04-2004, 08:16 AM
I wish i could compare mine to something but i just bought it with 50k on the od. I guess ill look harder for the kick at 3k but cant say that there is any night and day difference at that rpm.
Before you do anything, check fuse #10 to make sure it is okay.

Then do a physical and visual check. Between the back of the engine and the cowl you will see (2) flexible cables looping up from the IMRC control module and then down to the IMRC levers. While leaning over the right fender, grab the right cable and rev the engine up over 4K RPM. You should feel the cable sheath stiffen as the cable within pulls the IMRC lever to the open position. Then get your face down in there where he cable extends down to the right IMRC lever. It is just barely visible. Then rev the engine up several times over 4K RPM. You should be able to see the lever move. If it don't move, it's stuck or the control module is shot.

After replacing my control module I first thought things still weren't working. First, I was so used to hearing a 'click' when they opened, and that 'click' isn't present with the new module. After examining the old module I concluded that no 'click' is correct. The sound was made by the motor within the module slamming into its mounting brackets. Apparently it was a bit loose due to deterioration of the rubber holddowns. As for the kick, I didn't notice initially probably because the PCM had to come back from having the battery disconnected, and I wasn't really able to move out (get into the boost) going around the block in my neighborhood. Subsequent adventures have proved its working well!

overkill91
11-12-2004, 12:32 PM
Thanks for the good info. Ill take a look at everything this weekend.
The one thing i have noticed is that there is a dead spot at 3250 or so especially when the car is cold. If you are holding part throttle and allow the engine to rev past this mark there is a dead spot in the power.
Also, at WOT it seems like the power is inconsistant. I can really feel a drop in power around 5k or so for some reason (mainly in second gear). My check engine light is also on so im going to get the codes today and see what happens...
BTW, sorry to but in with my problems on this post.

SNAKEYE
11-15-2004, 07:58 AM
Thanks for the good info. Ill take a look at everything this weekend.
The one thing i have noticed is that there is a dead spot at 3250 or so especially when the car is cold. If you are holding part throttle and allow the engine to rev past this mark there is a dead spot in the power.
Also, at WOT it seems like the power is inconsistant. I can really feel a drop in power around 5k or so for some reason (mainly in second gear). My check engine light is also on so im going to get the codes today and see what happens...
BTW, sorry to but in with my problems on this post.
I have the same 'dead spot' when the engine is cold too. I just isn't ready for the second intake to come on line. I don't know how the Vortech is programmed, but I imagine it's set to come on line around t 3250 RPM too so that all works together efficiently. BUT AFTER THE 'DEAD SPOT' LOOK OUT!
If you have a CE light the engine is not going to run right. It's like in a 'limp home mode'. All performance is forgotten. It figures you aren't supposed to be at 5K RPM when something isn't right, so it holds back. Get back with the DTC numbers and/or what the diagnostician said about the CE light.

tcrews
11-15-2004, 08:22 AM
If you have a CE light the engine is not going to run right. It's like in a 'limp home mode'. All performance is forgotten. It figures you aren't supposed to be at 5K RPM when something isn't right, so it holds back. Get back with the DTC numbers and/or what the diagnostician said about the CE light.
It depends on what has triggered the CE light. About 80% of the things that turn the CE light on do NOT affect performance. The light being on is absolutely no indication of loss performance. You need to have the codes checked to see what triggered the light. Your engine will run 100% power with the CE light on unless it's one of the few events that actually puts you in "limp" mode. The CE light does not mean you are in "limp" mode.

overkill91
11-15-2004, 11:58 AM
It was a 02 sensor code. I think it was like bank 1 sensor 2. Ill have to look when i get home. I did call a few places though and they said it was a rear sensor.

Im going to try and make it to a auto store to remove the code and see what happenes. I currently have a different set of MIL Eliminators on the car.

SNAKEYE
11-15-2004, 12:49 PM
It was a 02 sensor code. I think it was like bank 1 sensor 2. Ill have to look when i get home. I did call a few places though and they said it was a rear sensor.

Im going to try and make it to a auto store to remove the code and see what happenes. I currently have a different set of MIL Eliminators on the car.
So, 'tcrews', is an O2 sensor in the 20-percentile bracket of things that will effect performance?

Exactly what code(s) (by the numbers) did you come up with 'overkill91'?

With 50K miles on the odometer one might expect O2 sensors to start having problems. I don't know what Ford expects to get out of them longevity-wise, but I had a '90 Chevy 4-banger that got just over 60K, a '98 VW that went 65K, and a '95 Chrysler 3.0L V6 still going at 85k. With the Vortech, SNAKEYE's tailpipes are heavily coated with carbon, but no complaints from the O2 sensors (knock on wood!) or the emmisions tester.

overkill91
11-15-2004, 01:36 PM
I will post in the code later but i think it was like ph0136? Its written on a piece of paper at home.

So its not abnormal for the IMRC's to freeze at ~3K? Mine still do it a little even when its warm. Much worse when cold though.

overkill91
11-15-2004, 08:32 PM
Ok, here is the code.

P0136 O2 sensor circut malfunction
Bank 1 sensor 2

Any thoughts?

SNAKEYE
11-15-2004, 09:25 PM
I will post in the code later but i think it was like ph0136? Its written on a piece of paper at home.

So its not abnormal for the IMRC's to freeze at ~3K? Mine still do it a little even when its warm. Much worse when cold though.
I wouldn't call it "freeze"! The engine and controls just aren't ready for the sudden drop in vacuum that occurs with the sudden opening of the IMRC plates. They literally 'snap' open instananeously. A cold engine stumbles a bit. The message here might be to not go there (3250 RPM) until the temperature has reached normal. The recovery can be a kick!

overkill91
11-15-2004, 09:27 PM
SNAKEYE, does yours still do it when the engine is warm?

overkill91
11-15-2004, 09:52 PM
Before you do anything, check fuse #10 to make sure it is okay.

Then do a physical and visual check. Between the back of the engine and the cowl you will see (2) flexible cables looping up from the IMRC control module and then down to the IMRC levers. While leaning over the right fender, grab the right cable and rev the engine up over 4K RPM. You should feel the cable sheath stiffen as the cable within pulls the IMRC lever to the open position. Then get your face down in there where he cable extends down to the right IMRC lever. It is just barely visible. Then rev the engine up several times over 4K RPM. You should be able to see the lever move. If it don't move, it's stuck or the control module is shot.

After replacing my control module I first thought things still weren't working. First, I was so used to hearing a 'click' when they opened, and that 'click' isn't present with the new module. After examining the old module I concluded that no 'click' is correct. The sound was made by the motor within the module slamming into its mounting brackets. Apparently it was a bit loose due to deterioration of the rubber holddowns. As for the kick, I didn't notice initially probably because the PCM had to come back from having the battery disconnected, and I wasn't really able to move out (get into the boost) going around the block in my neighborhood. Subsequent adventures have proved its working well!


Ok, i tried everything and it all checked out. Fuse was good, i could feel the cable and lever moving.

tcrews
11-16-2004, 08:19 AM
So, 'tcrews', is an O2 sensor in the 20-percentile bracket of things that will effect performance?
Depends on which O2 (front or rear). If it's the rear O2.....no performance change period no matter what the code. If it's the front O2 then it could cause some depending on the situation (too rich and you'll lose some performance but not much, too lean and it'll try to add fuel/pull timing and if that doesn't help it can drop to "limp" mode).

SNAKEYE
11-16-2004, 09:33 AM
SNAKEYE, does yours still do it when the engine is warm?Yes, but less perceptable. If you sneak the RPM's up to the point of their opening it will be much more noticable. Less noticable if you go straight to WOT.

SNAKEYE
11-16-2004, 09:36 AM
Ok, i tried everything and it all checked out. Fuse was good, i could feel the cable and lever moving.
Then all is well. You might try running a couple of bottles of fuel system cleaner through the system. You can't drive around blasting through 3250 RPM all of the time, but when you do the cleaner can get to the IMRC plates.

SNAKEYE
11-16-2004, 10:51 AM
Ok, here is the code.

P0136 O2 sensor circut malfunction
Bank 1 sensor 2

Any thoughts?

After reviewing the diagnostic routine for the P0136 code, it is evident that there is much special equipment required to do a complete check.

The service manual says "P0136 and P0156 indicate the output voltage of the downstream HO2S is less than some calibratable functional window."

Possible causes: Wiring Concerns - Pinched, shorted, and corroded wiring
and pins
-Crossed sensor wires
Other Concerns - Exhaust leaks
- Contaminated or damaged sensor

It goes on to say "Any exhaust leaks between the engine andthe end of the catalyst can cause DTCs P0136 and P0156." Then, inspect the following:
- Exhaust flanges for leaks
- HO2S torque
- Check for punctures and cracks in catalyst and pipes leading to them.
Replace or service as required.

I am not familiar with the MIL's you mentioned somewhere. If they ever did what they were intended to do, they might be malfunctioning. Or their wiring/connections may be having problems. Such mods can create headaches, especially if originally poorly installed and you become the subsequent owner. If there are any ground connections involved with MIL installation, make sure the connection is clean and tight.

After eliminating all of the possible obvious reasons for the CE light, I'd go for a replacement O2 sensor, or two, or four. Could get pricey!

Abneriel
11-19-2004, 09:36 AM
ended up cleaning them...with the mileage on my car I figured it wouldn't hurt. Here's what the IMRCs looked like...sorry about the size.

http://img.photobucket.com/albums/v216/Scarabgoddess/DCP_1877.jpg
and the intake manifold...
http://img.photobucket.com/albums/v216/Scarabgoddess/DCP_1878.jpg

Job took a while. I am not a mechanic by any means. Only real experience is swapping out the brakes...changing oil...etc. I used the web instructions and everything turned out well. Also used a Haynes manual for the TQ sequences. Didn't find it too hard, just time consuming. My back really hurt for the next few days from bending over the engine for extended periods. Ended up using 12 cans of carb cleaner to get all the junk off. Found that the TB had a crust of carbon behind it as well and cleaned it while it was there. I can feel a difference in the throttle response and a bit more power above 3250. When they were clean they looked like the clean pics in the instructions...

SNAKEYE
11-19-2004, 12:52 PM
At 43K miles mine didn't look anything like those, or the ones pictured in those procedural instructions. But then that wasn't my problem. Maybe the Mobil gas I usually burn really does clean your engine while you drive!:D
The procedure is down-right grunt work: drain, unscrew, clean, rescrew, refill. With lots of deep knee bends and stretching over the fenders, punctuated with carb cleaner fumes and interrupted by shedded latex gloves. On re-assembly, I left the cable ends off of the IMRC levers due to the way the intertwined with the fuel lines and electrical cables running behind the engine. Re-connecting them to the IMRC levers after all was bolted down was a real treat too.:rolleyes:
All's well that ends in the well!:)
SNAKEYE is getting closer and closer to Winter hibernation time. :(

Abneriel
11-19-2004, 01:10 PM
At 43K miles mine didn't look anything like those, or the ones pictured in those procedural instructions. But then that wasn't my problem. Maybe the Mobil gas I usually burn really does clean your engine while you drive!:D
The procedure is down-right grunt work: drain, unscrew, clean, rescrew, refill. With lots of deep knee bends and stretching over the fenders, punctuated with carb cleaner fumes and interrupted by shedded latex gloves. On re-assembly, I left the cable ends off of the IMRC levers due to the way the intertwined with the fuel lines and electrical cables running behind the engine. Re-connecting them to the IMRC levers after all was bolted down was a real treat too.:rolleyes:
All's well that ends in the well!:)
SNAKEYE is getting closer and closer to Winter hibernation time. :(

definately grunt work...

although I don't think that the IMRCs would be cleaned from the gas as the injectors dont touch those ports or the valves. I use nothing but Chevron gas in mine and the ports where the injectors spray were very clean (pics shown show after a spray of carb cleaner...which is why they are shiny and there is crap on the outside of the ports) where the IMRC ports were...well, you can see in the pics. Also, the valves adjacent to the IMRCs looked like crap where the valves touched by the injectors were clean. Maybe it was the mileage? I guess in reality it could be a lot of things.

SNAKEYE
11-22-2004, 12:38 PM
definately grunt work...

although I don't think that the IMRCs would be cleaned from the gas as the injectors dont touch those ports or the valves. I use nothing but Chevron gas in mine and the ports where the injectors spray were very clean (pics shown show after a spray of carb cleaner...which is why they are shiny and there is crap on the outside of the ports) where the IMRC ports were...well, you can see in the pics. Also, the valves adjacent to the IMRCs looked like crap where the valves touched by the injectors were clean. Maybe it was the mileage? I guess in reality it could be a lot of things.
It's all got to do with the air/fuel mixture (and the additives contained within the fuel) reaching the surfaces involved. The square ports are much cleaner because they have air/fuel flow 100% of the time, whereas the round ports, within which the IMRC valves operated, are closed most of the time (unless you driving around with the tach hovering around 3500 R's!). A periodic bottle of injector cleaner probably would minimize the buildup in the IMRC ports. I dump one in about every 3000 miles thrughout my 6000-mile driving season. Could be why mines weren't loaded with crud!

overkill91
11-22-2004, 10:12 PM
Well i did notice a difference after using some Cheveron Techtron. I also ran some Lucas fuel cleaner but couldnt really tell if it helped. Anyone have good results in a certain fuel system cleaner.
I need to reset my computer since i have some other mils on now. I think ill still clean my IMRCs anyway just to see what everything looks like. Probably wont be in any hurry though.
Thanks for all your advice.