Mechanics

3.8V6 CUTS OFF WHEN YOU LET OFF OF GAS PEDAL INSTALLED NEW ISC BUT NEED TO NO WHERE TO ADJUST IT MOUNTING BRACKET. AND IT IS A C.F.I CAR

1985 Ford LTD • 220,000 miles

Replaced T.P.S and then noticed the I.S.C was not working to control idle way to high so I unpluged it and adjusted the mounting bracket down so the idle would go down. Order new one installed it now I need to know to set it for idle. First it drove fine then after about 10 miles everytime you let off gas it cuts off.
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I learned the same thing about 10 years ago all my dad's 1986 Ford Thunderbird.

THIS IS WHAT WE ARE TALKING ABOUT?

http://www.autozone.com/autozone/parts/1985-Ford-LTD/Idle-Speed-Control-Motor/_/N-ijot3Z9gsoi?filterByKeyWord=MOTORS&fromString=search

Do you have a tachometer/dwell meter?

What we must do is adjust base idle is the ISC in the retracted position right now, out-of-the-box?

I just got Dragon for Christmas and this is the first question I'm trying at on.

Base idle on my dad's 3.8 was 400 RPM----YOURS MAY BE THE SAME, OR ON A DECAL UNDER THE HOOD

OK THE DRAGON (TALK, NO TYPING) IS NOT UP TO SPEED YET (STILL NEEDS TO LEARN MORE) SO I WILL JUST HUNT AND PECK AGAIN

I MESSED WITH THE IDLE SCREW AND GOT EVERYTHING OUT OF SYNC---THE ENTIRE SYSTEM RELIES ON THE "BASE IDLE" TO SYNCHRONIZE THE COMPUTER TO THE REST OF THE SENSORS ETC.

THE WAY I WAS SHOWN (WITH IT CONNECTED AND EXTENDED), I HAD TO CRANK IT UP AND SORTA QUICKLY PUT MY FINGER IN BETWEEN THE ISC TIP AND THE PLATE(THROTTLE ARM)

WHEN YOU DO THIS--THE THROTTLE GETS KINDA HIGH---BUT THE ISC WILL RETRACT IN (TRYING TO SLOW THE ENGINE SPEED) WHEN IT'S FULLY RETRACTED HAVE YOUR BUDDY UNPLUG THE WIRE TO IT....NOW PULL YOUR FINGER OUT!.....BEST TO HAVE THE CONNECTOR SORTA HALF CONNECTED SO YOU CAN DO THIS FAST!

THE BEST TIME TO PERFORM THE ADJUSTMENT IS WITH THE ENGINE AT OPERATING TEMP......GET IT THAT WAY 1ST (BEFORE YOU RETRACT THE ISC OR NURSE IT ALONG WITH THE PEDAL)....JUST GET 'ER DONE!

IF YOUR NEW ONE IS RETRACTED RIGHT OUT OF THE BOX---INSTALL IT BUT DO NOT PLUG IT IN YET (IF YOU DID, AND NOW EXTENDED--BACK UP 3 PARAGRAPHS)

OK , ISC IT NOT TOUCHING

HOOK UP THE DWELL/ TACH TO THE NEG SIDE OF THE COIL AND A GROUND

CAR IS OPERATING TEMP---ADJUST IDLE SCREW TO 400 RPM (OR TO YOUR FINDINGS) MOST LIKELY 400 ON THE 3.8

MAKE SURE YOU ARE HAPPY!

TURN CAR OFF

PLUG IN ISC

TURN CAR ON....WAIT A FEW SECONDS...ISC EXTENDS HITS PLATE...EVERYBODY IS "ZEROED UP" AGAIN!

CRANK

STICK YOU WITH A FORK---YOU ARE DONE!

SOUND LIKE YO CAN DO THAT?

UNDER THE HOOD---WATCH OUT FOR THOSE PESKY MOVING PARTS!

ANY QUESTIONS?

MY DAD'S CAR HAD THE SAME "CUT OFF PROBLEM"

THAT'S HOW I LEARNED THE ABOVE

IMMA JEEP KINDA GUY, BUT I TRY TO HELP ALL I CAN

I'LL COPY AND PASTE MY DEALINGS WITH IT FROM ANOTHER POST---IF IT MIGHT HELP IN ANY WAY....PASTING

Had similar problem with my Dad's '86 T-Bird, on his it was inability to idle (sometimes it would, sometimes not).........It was the injectors, they are not "Monitored" by the Computer, The computer just "operates" them. However when they act up, they do make other things throw codes randomly.

The 1st thing we did was the coding w/ the Scanner--It take s a bit to catch onto--listening/ watching the flashing light/ beeps and counting---watching it go thru a sequence

I was pulling my hair out and made several trips to the salvage yard and obtained nearly every sensor (2-3 of each) off of T-Birds and Cougars

I thought surely they all cannot be bad, I got a bagful for like $10!

My intentions were to figure out which one was being evil----THEN BUY A NEW ONE!

My Dad and I wound up taking it to the feller that the stealerships take their problem cars to.....he let me watch the process.

Everything was in perfect order, He put stuff on an oscilloscope, and explained what he was doing...the only thing he came up with that was not perfect was the TPS--I had replaced it with 2 from the salvage yard and wound up buying a new one from Advance Auto (This new one was supposedly bad)

This feller even confirmed "Base Idle" was dead on (another learning experience). Don't mess with the adjustment screws--I learned that throws the computer out of sync with the sensors---there is a specific procedure to get it right----at least I had got it right before this guy checked it out

Dad paid the feller $200 and off to the stealership for the "OEM TPS".....It's cost was much more than Advance Auto

Guess What????

This did not work, in fact, I took it back and got another

Same deal.....will not idle! (NOTHING WRONG WITH THE ONE FROM ADVANCE AUTO!, OR THE OTHERS!)

I was on the Verge of Suicide.

My buddy had went back and got the whole throttle body off of a wreck that had low miles, for $20.

I laughed when he showed up and gave it to me.

He said this is the only thing we haven't tried, the price was right!

Every other knowledgeable person (I talked to many, many people) insisted it was a sensor problem and I had spent a MONTH changing everything in the world.

I even had a composition notebook started w/ what I had done, the various code changes I got, How it ran, how long before it would not idle

It was the Two INJECTORS the Whole time!

Need a Bagful of sensors?

I am not a Paid Mechanic (as you can see) I do know Jeep CJs very well (They don't have a computer)

I hope this could be your problem, maybe you can try some used ones prior to buying new ones, just to be sure.

You could just use the excuse I use to justify getting new parts, whether it's the problem or not---"It's gotten the car to $300,000 miles already, something new is just preventative maintenance...the car is paid for, this is way less than one payment on a new one!"

THIS IS WHAT I MEAN BY "NOT MONITORED" BY THE COMPUTER---FUEL BURN IS MONITORED....THE COMPUTER REACT AND "TELLS" THE INJECTORS TO REACT...MORE FUEL OR LESS FUEL

WHEN IT TELLS THE INJECTORS TO GIVE IT MORE FUEL SO IT WILL IDLE, AND THE INJECTORS ARE INCAPABLE OF DOING SO (MESSED UP)---IT WILL THROW VARIOUS RANDOM CODES---AND THE ENGINE DIES (EVERY CODE THAT WAS THROWN POINTED TOWARD A SENSOR PROBLEM)

THE INJECTORS IN A '86 THUNDERBIRD ARE "DUMB", IT DOES NOT "SPEAK" TO THE COMPUTER IN NO WAY, SHAPE, NOR FORM, TO TELL MR. COMPUTER IT IS SICK

BEING THAT PAP'S WAS EMITTING TOO LITTLE FUEL AND YOURS IS EMITTING TOO MUCH---I KINDA FIGURED THAT MAYBE YOUR INJECTORS WERE SICK ALSO

I'M SHARING MY EXPERIENCE SO THAT YOU MAY POSSIBLY EXPLORE THE OPTION THAT FINALLY FIXED THE PROBLEM

I TOO LISTENED TO EVERYONE ELSE SAID TO BE "THE MAN"...OR..."IF HE CANNOT FIX IT NOBODY CAN".....OUT OF A DOZEN OR SO COMPETENT MECHANICS WE SPOKE TO, NONE SUGGESTED THE INJECTORS.

EVEN WITH THE HEADACHES AND TIME, I STILL FEEL WE STILL GOT OUT WAY MORE CHEAPER THAN AT THE STEALERSHIP

I TYPE VERY SLOW AND I WOULD NOT WASTE MY TIME TRYING TO MISLEAD YOU, I JUST TRY TO HELP AND OFFER LESSER EXPENSIVE OPTIONS

I WILL CONTINUE TO FOLLOW THIS QUESTION, BUT RESPOND NO MORE....UNLESS YOU RESPOND TELLING ME I WAS RIGHT....THEN I WILL DO MY VICTORY JIG AS MUCH AS I CAN IN TEXT!

PLEASE CONTINUE TO REPORT BACK, UNTIL YOU ARE FIXED

GOOD LUCK AND MAY THE FORCE BE WITH YOU

The Medic



Tiny
CJ MEDEVAC
Jan 6, 2012.


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