Imrc Relay ????

[SNAKEYE]

Over the last week or so I noticed that the kick in the pants at 3250 RPM's seemed to be non-existant. I also noticed that under WOT and full boost there is a bit of a lack of the old pull above 6K RPM. Then this A.M. I took it really easy and quiet in order to be able to hear the IMRC relay click. No click did I hear.

No kick, no pull, no click. CONCLUSION: NO RELAY!?

I've spent some time perusing my CD service manual and have not yet discovered the relay in any descriptions or wiring diagrams, let alone a hint as to the physical location of the relay.

Therefore, is anyone out there able to tell me where to find it? It is in the dashboard, somewhere possibly right-center from what I could hear when I could hear it.

I need to get the click, kick, and pull back. HELP!

[SNAKEYE]

Oh wow, I think I got lucky and found the IMRC in the CD service manual!
What I thought sounded like a relay clicking in the right-center of the dash apparently is the IMRC itself, which is mounted on the back of the induction plenum, that I heard right thru the firewall.
I also find that there is an instrument panel fuse involved (#10).
I had a problem with my hardwired radar detector supply wire about two weeks ago. Maybe it was piggy-backed on the IMRC fuse and blew it?!
I will check things out tonight and let the board know how things turnout incase anyone else develops a similar symtom with the IMRC.

:o

[SNAKEYE]

Originally posted by SNAKEYE
Oh wow, I think I got lucky and found the IMRC in the CD service manual!
What I thought sounded like a relay clicking in the right-center of the dash apparently is the IMRC itself, which is mounted on the back of the induction plenum, that I heard right thru the firewall.
I also find that there is an instrument panel fuse involved (#10).
I had a problem with my hardwired radar detector supply wire about two weeks ago. Maybe it was piggy-backed on the IMRC fuse and blew it?!
I will check things out tonight and let the board know how things turnout incase anyone else develops a similar symtom with the IMRC.

:o

Not so lucky last night. The IMRC fuse is just fine.
Based on some info supplied by one of the members of our local SVTOA chapter, there are two maladies that afflict our '96-'98 Cobra's IMRC setups: sticky runner mechanisms and burned out IMRC motors. Cleaning of the mechanism, as well as replacement of the IMRC unit containing the motor both involve removing the air intake cover and induction sytem within to access either the mechanism for removal and cleaning, or the changing out of the IMRC unit itself.
Before I dig that deep I am going to try some manual manipulation of the mechanisms linkages to hopefully free them if they are stuck. I can't imagine they are stuck as they are generally well exercised! But, maybe they could be. Once freed they should operate, at least temporarily, normally. If not, it's possibly the IMRC motor. I say possibly because possible problems with the PCM and the wiring still exist. I plan to do some OBDII testing and some testing of the wiring to negate the possibilities of either being the culprit. At 40K miles anything is a possibility.
I am open to any cleaning suggestions that do not involve pulling the air intake system off of the engine.

[PETSNKE]

IMRC cleaning is a pretty common problem.

Here's a nice "How To" write up I came across some time ago.
http://www.svtmustangcobraclub.com/media/pdfs/tech/IMRC_Cleaning.pdf

[Sharppony]

Snakeye, keep us informed. I'm curious to know what the problem is, perhaps it is preventable. Thanks.:cbra:

[SNAKEYE]

Originally posted by Sharppony
Snakeye, keep us informed. I'm curious to know what the problem is, perhaps it is preventable. Thanks.:cbra:

Well, yesterday I had a few minutes, so I went poking around the engine compartment. I found the cables that lead to the levers on the ends of the IMRC rods. I formed a hook on the end of a piece of coat hanger wire and lassoed the levers (1 each side). When I pulled up the levers rotated the IMRC rods, so the things are not stuck in the closed position.
So the problem is either wiring or the IMRC unit mounted beneath the intake manifold. I won't be able to do a teardown until mid-June.
In the meantime, after a discussion with a '96 Cobra owner (and director of our chapter of SVTOA) who indicated some people remove the IMRC completely, while I was in there with the heavy coat hanger wire I decided to wire the IMRC's open. It was relatively easy: lasso the lever with a hook formed on the end of the coat hanger wire and wrap the othere end over the strut tower brace near the firewall. Done.
As suspected, there seems to be a bit less grunt at lower RPM's under WOT operation. Normal driving seems perfectly normal, even smoother (for lack of a better word). The pull seems to be back in the upper RPM's.
Even though it seems to run okay at higher RPM's, I liked, and now miss, that kick when the IMRC opens at 3250 RPM. Based on the article I got from yet another SVTOA member or two, I'll be doing the teardown to get to the root of the problem, and get back that kick!
See you all at Carlisle!

[MNavycowboy1]

I heard there was a kit to remove the IMRC, I dont want to "rig" my car I want it to work but I am just having to much truble with my dang IMRC. I need help!!!