PULLS IDLE DOWN AND CAR QUITS

1985 Lincoln Town Car

Tiny

rodney fuller

December, 17, 2011 AT 1:32 AM

85 towncar idles ok while in Park with out ac on. But with ac on and in drive, pulls idle down and car quits in drive, and at red light, and on takeoffs. Please tell me if a part is bad, or a switch has gone bad to equal idle between ac on/ ac off. Thanks in advance!

This is my Moms & Dads car. It Is In Great Shape, Always Cared For, And Repaired When Needed, But No One Seems To Know what Is Wrong.I Just Had It Totally Tuned By Professional, But he Says, He Has No Clue. I Know this Is Not right. The Older Cars Had A Device That Changes idle W/ac ON W/ac Off. Please Help, It's Hot In South Florida.

THANK YOU IN ADVANCE. Rod F.

FOUND 1919 RELATED QUESTIONS

8 Answers

Tiny

rivermikerat

December, 17, 2011 AT 1:53 AM

Check for vacuum leaks and proper fuel pressure.

Tiny

rodney fuller

December, 17, 2011 AT 2:17 AM

That Has Been Done All OK, What About Ajustmenst For Idle Up/Down?
With Foot Just A Little On Peddle Idle And All Is OK, How Can I Adust The Idle Up A Little?

Tiny

CJ MEDEVAC

December, 17, 2011 AT 2:51 AM

HOW 'BOUT LET'S CHECKIN' SOMETHING STUPID!

YOU SAY IT BOGS DOWN W/ A/C ON---MAY DO THE SAME W/ DEFROST TURNED ON

YOU DID NOT SAY YOU WERE GETTING "COOL" WITH THE A/C ON. BOGS BEFORE YOU COULD NOTICE?

LET'S GET SOMEONE TO WATCH THE A/C PULLEY BEFORE, DURING, AND AFTER IT'S ENGAGED INSIDE THE COCKPIT

WHAT WE ARE LOOKING FOR IS THE INNER MOST PART OF THE PULLEY(CENTER) TO SPIN AT THE SAME SPEED AS THE OUTER BELT DRIVEN PART. NOT STOPPED, NOT SKIPPING, NOT SQUEALING OR MAKIN' A RACKET

IN OTHER WORDS. IS THE COMPRESSOR LOCKED UP. AND ALL IS GOOD UNTIL THE CLUTCH ENGAGES THE COMPRESSOR

ON MOST MORE MODERN CARS THE "DEFROST MODE" OF THE HEATER WILL ENGAGE THE COMPRESSOR (THIS LETS THE EVAPORATOR REMOVE MOISTURE FROM THE AIR, BEFORE AIR IS BLOWN AGAINST THE WINDSHIELD)

IF THIS "IS" THE SITUATION, YOU HAVE THREE OPTIONS: 1) REPLACE THE COMPRESSOR (BEST CASE)

2) DRIVE THE CAR WITHOUT A/C OR ANY HEATER MODE THAT USES "DEFROST" (IN OTHER WORDS, BE AWARE OF HVAC SETTINGS, WITHOUT MAKING THE COMPRESSOR COME ON---AFTER A WHILE, YOU MAY BREAK OR BURN YOUR BELT OFF. IF NOT CAREFUL

3) IF YOU MUST (LIKE THE GOOD OLD DAYS)---UNPLUG THE COMPRESSOR CLUTCH UNDER THE HOOD (NOW IT WILL NOT ACCIDENTALLY BE TURNED ON)----ALL OF YOUR HEAT SETTINGS, DEFROST, AND ALL WILL WORK (JUST NO MOISTURE ASSISTANCE. JUST LIKE YESTERYEAR!)WANT SOME AIR. ROLL THEM WINDOWS DOWN, THAT WAS THE ORIGINAL REASON THEY WERE DESIGNED!

I LIKE GIVING PEOPLE EVERY OPTION---I'M NOT ONE TO SAY "YOU MUST FIX THIS TEXTBOOK, OR IT AIN'T RIGHT".I'VE HAD TO MAKE DO W/ STUFF MYSELF. WANTED YOU TO UNDERSTAND YOU "CAN" STILL RIDE, W/ SOME COMFORT LOSS.I'D MUCH RATHER BE HOT, THAN A LITTLE COLD!

KEEP US INFORMED, WE STILL MAY BE ABLE TO ASSIST FURTHER

THE MEDIC

Tiny

rivermikerat

December, 17, 2011 AT 3:18 AM

Idle adjustment on carbureted vehicles is done by turning the idle adjustment screw on the driver side of the carburetor.

On fuel injected vehicles, this is called the idle air adjustment screw and is on the side of the throttle body.

Both of these can be adjusted with a small flat screwdriver. On carbureted vehicles it may require removing the air cleaner housing to get the screwdriver on the screw head.

Tiny

rodney fuller

December, 17, 2011 AT 4:28 AM

Sorry!Maybe I Can Say This In A Different Way. AC Is New. Only 6 months old,
And Working great. The Idle Is Too Low, Which then. Car will stall when leaving from all stops. The Car wants To Die Because of too low of idle. When the AC Is Not On/Compresser is not Running! Idle Is OK. But still Not To My Standards But Will Do, The Car runs like new, other then low idle, and stalling on take offs What Part Or What Can be done to adust idle/This Car from Factory Has no air/fuiel mixture adjustments. Thanks once more. RF ps Car Was Also Checked for vac. Leaks

Tiny

rivermikerat

December, 17, 2011 AT 5:01 AM

Idle Mixture Plug Removal
Remove carburetor from vehicle. Drain fuel bowl. Drill a 3/32" hole in mixture screw plug. Use a
screw extractor to remove plug. Install carburetor and make adjustments. After adjustment, install
new mixture plug.

If injected, it requires a scantool/programmer to adjust the idle speed.

Tiny

rodney fuller

December, 17, 2011 AT 1:30 PM

Great Job! Scantool Prorammer Is Want Makes Alot Of Sense At This Time, I Will Get The Part Right Away.I Will Then, Let You know If This Corrects The Problem, I Feal You Nailed It!
THANKS again Rod Fuller

Tiny

rivermikerat

December, 17, 2011 AT 7:21 PM

My pleasure. Festive Yule and Happy New Year.

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