Re: Hanging/Slow dropping RPM FIX inside.
 

I noticed my Mach having problems when the hole in the plate was 9/32s. I uped it to 11/32s and haven't had any problems since. Checked my A/F and it's running around 13.2.

Re: Hanging/Slow dropping RPM FIX inside.
 

I had to do the same thing because mine idled very erractically with a 9/32" hole. My restrictor plate has been in since early last summer, and only recently the idle started hanging around 1200 rpm again. May be something to do with Diablo tune version r50c/running lean, so I will probably monkey around with that and see what effect it has.

Re: Hanging/Slow dropping RPM FIX inside.
 

Well, I've got some good news! Never was too sure by reading the posts on here whether I had the same problem as ya'll or if I had my own seperate problem, but Ford found my problem this morning and fixed it!

I posted a thread in the Technical, TSB thread section called High Idle Problems.

http://www.mach1registry.org/forums/...668#post294668

Re: Hanging/Slow dropping RPM FIX inside.
 

GREAT MOD. THANKS. I DO HAVE ONE PROBLEM. MAYBE SOMBODY OUT THERE HAS HAD THE SAME. I WENT WITH THE 9/32 SECOMD HOLE LIKE YOU REC. LOVE THE IDLE DROP AND THE (BURBLE). MY PROB. IS THAT I HAVE A HIGH IDLE(1100-1300RPM). EVERY KNOW AND THEN IT WILL CUASE A CKECK ENGINE LIGHT. I AM LUCKY ENOUGH TO BE ABLE TO SCAN MY OWN CAR AND THE CODE THAT POPS UP IS P0507-IDLE CTRL SYSTEM RPM HIGHER THAN EXPECTED. DID I DO SOMTHING WRONG OR IS THIS NORMAL FOR THIS MOD. UNFORTUNATLY I AM GOING TO TAKE THE PLATE OUT TILL I CAN FIND OUT WHAT IS WRONG. ANYBODY GOT ANY SOLUTIONS. THANK :hail1:

Re: Hanging/Slow dropping RPM FIX inside.
 

I've done two cars with my homemade IAC plates, no problems. Did you disconnect the battery and do the idle thru drive cycle procedure for the computer? If you did this already it maybe an unrelated problem. If under warranty, take or keep the plate out and get it fixed. Good luck, let us know what the problem is.

Re: Hanging/Slow dropping RPM FIX inside.
 

It could also be that the hole maybe too small. Every Mach is different and depending on your location could have this effect. I would recommend enlarging the hole to 11/32s. I've had great success with it at that diameter.

Re: Hanging/Slow dropping RPM FIX inside.
 

:agree:

I reinstalled an older Diablo Predator tune (r42b) and the high idle all but disappeared, with a restrictor plate with a 11/32" diameter smaller hole still installed.

Re: Hanging/Slow dropping RPM FIX inside.
 

WELL I TRYED THE 11/32ND HOLE TODAY. THIS IS WHAT HAPPENED. AT FIRST IT WAS WORKING FINE, THEN WHEN I WOULD LET OFF GAS THE IDLE NOW IS STICKING AT 1500-1600 FOR ABOUT 20 SEC. THEN DROPPING TO NORMALL. DROVE CAR FOR ABOUT 20 MILES THEN CHECK ENGINE CAME ON AGAIN. THIS TIME WITH 2 DIFF CODES THEN BEFORE. BOTH WERE FOR O2 SENSORS READING TO RICH AND STUCK IN OPEN MODE. THE NEXT STEP I AM GOING TO DO IS PUT A GASKET ON BOTH SIDES OF THE PLATE.MAYBE POSSIBLE I AM NOT GETTING A PROPER SEAL AND SUCKING AIR. WILL UPDATE TOMMORO. THANKS FOR THE INPUT.

AFTER I POSTED THIS MESS. I THOUGHT IT COULD HAVE SOMTHING TO DO WITH THE SUPER CHIP MICRO TUNER, SO TOOK THE PROGRAM OUT AND INSTALLED STOCK PROGRAM AND PUT THE PLATE BACK IN(11/32 HOLE0. BAD MOVE!!!! . I DONT KNOW WHAT HAPPENED BUT THE CAR RAN LIKE ABSOLUTE S?IT. REINSTALLED SUPER AND TOOK PLATE BACK OUT AND EVERYTHING IS BACK TO NORM. I DONT KNOW BUT IT LOOKS LIKE MY CAR JUST WONT EXCEPT THE PLATE????

Re: Hanging/Slow dropping RPM FIX inside.
 

:hail1: well after 8 days of playing with diff combos to try to get thr plate to work, i found the prob. in another thread we are having a discussion about the turbonator that i have in my car. well that was the prob. beleive it or not. i took the turbonator out today and installed the plate with the 11/32 hole and every thing is great :yeh: so now i will rather the quick drop rpms over the better gas miladge anyday. as i mention in the other thread i have a date with the dyno soon. i will be testing the turbonator to see the actuall numbers it produces or dosnt. when i get the numbers, be asured i will post them. thank for the great mod, but dont use it with the turbonator.

Re: Hanging/Slow dropping RPM FIX inside.
 

I'm gonna make these at the hangar where we have an aircraft Sheetmetal Shop. Not trying to make a profit... just helping out those who can't manufacture there own. $5.00 SHIPPED

Paypal... ruben.olivencia@us.army.mil

Re: Hanging/Slow dropping RPM FIX inside.
 

I just installed the plate with a 5/16 hole. Works great! Thanks;)

Re: Hanging/Slow dropping RPM FIX inside.
 

I've had nothing but problems with mine! Installed it Friday night and the car ran pretty good for about 5min, then the RPMS would hover around 1800/2000, and the car would drive itself, as well as having a far worse hang in the RPMs (11/32 plate). Took that plate out and tried and smaller hole (5/32) and the I thought it worked, until I noticed the RPM's hovering in the 1000-1300 range, then my SES came on. as far as I know I dont have a chip, BUT I bought the car used and its had plenty of surprises (4.10 gears, Slotted Rotors, looks like it had CC plates, Im still finding stuff!)

Anyone else have some input? Im removing the plate all together and seeing what happens, if it throws the light again, then its off to the dealer, if not, then its gotta be the plate, but I've put 3000 miles on the car prior to the plate with no SES lights...

maybe I'll try a larger hole and see what happens.

-Wes

Re: Hanging/Slow dropping RPM FIX inside.
 

When you say the car seems to drive itself, did you notice anything like this before the plate install? If so I may have some info for you.

Re: Hanging/Slow dropping RPM FIX inside.
 

Nope, started after the install. and when I say Drive its self, I mean the car would actually Accelerate until I was at 1800/2000 RPM.

Tried a larger hole last night and the car ran the same as it did when I took the plate out.

-Wes

Re: Hanging/Slow dropping RPM FIX inside.
 

Just Installed. Less Than Five Minutes. Works Great. Thanks!
Would Have Been Willing To Pay $40 For This.

Re: Hanging/Slow dropping RPM FIX inside.
 

Hmmmm...I don't know then? Sorry.

Re: Hanging/Slow dropping RPM FIX inside.
 

Weird.... Something ain't right there. Might have a faulty IAC. It can't be the plate. I've had mine in for over a month. No problems at all. All positive feedback from the ones I mailed to several guys and gals.

Re: Hanging/Slow dropping RPM FIX inside.
 

I wonder if I have an leak somewhere, the car will stall out sometimes (from time to time when I come up to a stop sign/light, the car will just die on me if I coast up, same with getting off the freeway)

I took it into the dealership and they said it was a bad PCV valve and it was replaced, Guess I'll have to look harder.

-Wes

Re: Hanging/Slow dropping RPM FIX inside.
 

I just came across this today, but it's something I've lived with for years now.. DUH!! My first mustang that I got in 2002 had this problem and yes it was annoying but I just never looked more into it. I just purchased a new 04 GT and it of course does the same thing. NOW i'm like, what the hell is with Ford?? SO, going to give this a try tonight and see what happens.. Definitely sounds like the ticket though!

Thanks a lot! GO CANADA GO

Re: Hanging/Slow dropping RPM FIX inside.
 

I made a plate for my Cobra engine (N/A) with aluminum and it fixed it right up.
No more RPM hanging.
Much nicer to shift with RPM match like a carbureted engine.
I used a 9/32 hole in mine.
Gasket at Ford was 68 cents.

Re: Hanging/Slow dropping RPM FIX inside.
 

I have this exact problem on my 2004 5 speed V6...I tried the restrictor plate, but it made the car run worse (the car would kind of stumble and the RPM hanging was sometimes WORSE) So I took it out and the car runs better, but the RPMs still hang...that fast idle TSB sounds like a good thing to check out...but I'm wondering if they would even look twice at it "becuase it's a v6 and not a v8" Stupid for dealers :rolleyes:

Re: Hanging/Slow dropping RPM FIX inside.
 

Earl, like a few others have posted, try different sizes. Thats why I recomment starting with the smallest hole, and keep increasing size and retrying until you find the best benefit.
I would rather spend 5 min pulling out the plate and making the hole bigger as few times...rather than spend 1 hour, make it once, and it doesn't work the first time so you forget it and live with your hanging RPM's...

Re: Hanging/Slow dropping RPM FIX inside.
 

If you have removed your Mass Airflow Sensor "Screen" then put it back in. It may take a little modifying but that has been known to help correct the lean condition. Also, Try rotating the MAF (Clockwise or CCW) slightly a few times. That may help also.
Hope this helps,
Frankie

Re: Hanging/Slow dropping RPM FIX inside.
 

I have a 2002 Mustang GT that has an IAC with only one hole. How would I go about doing this mod. Thanks

Re: Hanging/Slow dropping RPM FIX inside.
 

I made and installed a IAC Restrictor plate and loved it. I got best results with the 11/32 hole. I think anything smaller just makes the motor act wierd. :smokin: