Payback with interest for 3 trouble free years

skelly42

New Member
Feb 21, 2004
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:bang: Posted a bit on this earlier but now it's getting weird. Clutch went out on my 96 cobra at 88000. AFter some good responses in here and elswhere I chose a '99 11" Ford racing clutch kit and what I thought would be safe shop choice. A local mainstream tranny shop thats been here for years and years. Had to wait a week for parts but it only took a couple of days after that, they even came in on a Saturday to finish it up. Drove around a bit and to my horror ( after 760.00 ) it drove like crap. It had a horrible driveline vibration, an seemed to be missing to boot..

A few more questions in here and I called Monday morning and they somewhat reluctantly agreed to take a look at it Tuesday morning. My wife took it in and two mechanics agreed "something" twernt right. The manager called Ford and was told they either hadn't lined the paint dots up on the flywheel / pressure plate or, they admitted, that some bad flywheels had inadvertantly made it into the market which could take up to MONTH to replace. Holy crap. Turns out the mechanic didn't know the parts were balanced and had to be indexed. How scary is that? The ONLY do transmissions. So he had it 180 degrees off. They re-did the install, the manager took a test drive ( he test drove the first time and passed it as a-ok ) and passed it again, claiming all fixed for sure this time.

Yes it's better but it's not fixed. It has a buzz around 4500-5000rpm that'll make your hand numb on the shifter. How could he miss that? Then he tells my wife that he ran a diagnostic to check the missing ( which wasn't there when the clutch went ) and found a trouble code for the intake manifold runner control being stuck shut. And my research says that can be a mother ranging from bad computer to partially tearing out a LOT of stuff to get to the part to repair or replace.

It's like I traded my soul for three great trouble free years and now the Devils here to collect :(

So now I have an appointment with a dynotune shop to track down the IMRC problem, hoping that I wont get slammed to bad on that. And hoping against hope that Im mistaking a rough engine for a driveline imbalance because I'm pretty nervous about the capabilities of the tranny shop at this point.

So one.. anybody had a IMRC problem before? Cost ranges? And, if you were me, would you keep taking the car back to the same tranny shop until they figured it out or cut your losses and try to find someone more competent to try to iron out the problems? Do I have a chance in hell ( my current address ) of finding a shop who can iron this kind of problem out without just throwing more parts at it? I want my Cobra back!
 
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I would find a more competent shop, no offense.
Also, run a search on "IMRC" over in the SVT/DOHC tech section of corral.net 's msg board (you could try a search in here, but I don't know if anyone cross-linked it). There's quite a few threads about what to do in order to R&R the IMRC issue that so many 96-98s are facing...
 
Yeah, I'll second that. They had a link to a page with very well laid out and detailed instructions for breaking down the engine to get to the IMRC to pull them out and clean them. If you've got that many miles on her that may more than likely be an issue. They naturally get dirty from use and will eventually start to stick. Mine do it sometimes but it isn't nearly bad enough to make me want to tear the engine apart to clean them just yet. With a pair of competent guys and a set of good instructions it can be done in a day.

The only thing is that I don't think a stuck or dirty IMRC would cause a vibration like that in the transmission. A sticking IMRC will cause a lag pulse that feels like a loss of power at around 3200rpm. The pulse comes from the things sticking and not opening smoothly. What you described I've never seen or heard of before. I have a 96 as well so I look for crap like that and file it away in my mind for future reference.

The bad news is the buzz issue is a mystery to me. The good news is that if there is a problem, its most likely being caused by good parts simply being dirty. Good news is that they can be cleaned and you shouldn't need to replace them. Bad news is that it isn't impossible but it is a bitch to get them out.

I probably didn't help much but I hope I did. Good luck bro!
 
Hold your IMRC cable covers and have someone rev it over 3200 rpms. You should see and feel the controller pull the cable. If it gets tight but the IMRCs do not open then the IMRC plates are stuck. If nothing happens it is then the electronic controller.
 
LeadSled1 said:
Hold your IMRC cable covers and have someone rev it over 3200 rpms. You should see and feel the controller pull the cable. If it gets tight but the IMRCs do not open then the IMRC plates are stuck. If nothing happens it is then the electronic controller.

Um, dumb question probably :) But how do I know when they are open or not? How much difference does it make if they are stuck shut ( which the code says they are on bank 2 ) I'd guess that they were doing something good when they work, but how much good? This car had 50000 when I bought it and until my clutch problem I really can't say I noticed any specific problems or thought it was running any slower than when we got it.
 
If you are still getting the faulty IMRC and the cables are activated by the controller (cables go tight) the IMRC plates are stuck. If the cable never goes tight at 3200 you would have a bad controller. If it is only happening on bank 2 I would suspect the IMRC plates are stuck on bank 2 and not a faulty controller as bank 1 is opening and not tripping a code. The controller runs two cables, one to each bank to activate the plates. With the IMRC plates stuck shut on bank 2 that bank will not make power much past 4000 to 4500 rpms. With the other bank opening the car will rev higher but run like crap.

The 96-98 DOHC uses two intake ports from the intake manifold to the head. The IMRC plates block of one of the ports to keep air velocity up in the lower rpms. Around 3200 RPMS the controller activates and rotates the IMRC plates to open up the second port. This allows the motor to get the air it needs to keep making power in the upper rpms.

If it is just a stuck IMRC this does not need any additional parts. You can remove the intake manifold and carefully clean the IMRCs with carb cleaner and free them up. You will want to put something in the port to keep the debris you knock loose from falling down into the valve area.


Hope this helps,
Jess