20 Most Recent 1989 Mercury Grand Marquis Questions & Answers

a simple test here may reveal the fault
put the hand brake on and in neutral
start the engine
if it idles ok then put your foot on the brake
if there are problems then have the brake booster replaced
that is indicated because at lights , you have you foot on the brake
when turning people use the foot on the brake to maintain control

1989 Mercury... | Answered on Jun 17, 2017

a factory workshop manual will help you with the problems
ac moving from cool to heat means that the ac compressor is cycling from the thermostast setting
if you have climate control in use , that indicates a problem climate control module

1989 Mercury... | Answered on May 30, 2017

    If your car died suddenly while driving, it is one thing, if it just didn't start one day, it is another, but given you have not given enough information, start here. Always check fuse first, this will tell you if pump is shot in most cases. Then check fuel pump relay located left fender under hood in fuse box. There are three relays as I recall, and if fuse was good, then more than likely it is relay, if I recall, two of relays are same type, so swap positions to diagnosis, you should be able to hear the fuel pump running, so get a gift wrap paper tube and put it near fuel pump location on gas tank and you should hear it easily, so this will further narrow down problem if you can't hear it run.

    Good luck. FREE-PPV

1989 Mercury... | Answered on Dec 12, 2016

Two things pop immediately to mind...

but before even going there... be VERY CAREFUL 275 pounds seems terribly high for an '89... If something cuts loose at that pressure you best have all your helmets, flak jackets, gloves, glasses & cups on... (I'm just saying).

Pressure line should be hot and suction line should be cool... coming back to the compressor.. Yes...??

Lets get to the two things on my mind:

1. Malfunctioning Heater-A/C baffles cause lotsa grief.

2. Drier: Desiccant saturation by exposure to atmospheric moistures... replace or attempt recovery by pulling & holding a SERIOUS vacuum before re-charging your system.

ELSE: Ice crystals will form at the "ORIFACE" and PROFOUNDLY AFFECT PERFORMANCE...

Pulling & holding a 29 vacuum also certifies your main compressor seal (ergo... refrigerant & lubricant will remain intact)... Any trace of OIL BUILD-UP on the front of the COMPRESSOR (or inside the hood in alignment with your compressor pulley) should be addressed... oil level checked & augmented (only as needed)).

Hope this helps


http://www.rockauto.com/en/catalog/mercury,1989,grand+marquis,5.0l+302cid+v8,1199505,heat+&+air+conditioning,a/c+compressor+seal,6676 More Information for MOTORCRAFT YE57


More Information for SPECTRA PREMIUM COOLING DEPOT 0233168

1989 Mercury... | Answered on Aug 16, 2016

Someone will need to find out if it is fuel or spark to know which system to inspect.

1989 Mercury... | Answered on Nov 24, 2015

O2 sensors been changed lately?

1989 Mercury... | Answered on Aug 16, 2015

looks like excessive internal pressure in the engine; check your engine ventilation system and make sure any and all restictions are removed.

1989 Mercury... | Answered on Feb 04, 2015

With that Crossmember Broken It is putting a Strain on the Tranny. Replace the Crossmember and then Check your Linkage and the Bell housing Bolts on the Tranny.

1989 Mercury... | Answered on Dec 09, 2014

Wheel alignment and tire balance are the first place to look. if you feel vibrations in the seat. the rear wheels are the fist place to check. if vibrations are present through the steering wheel, then front tire alignment and tire balance are probably the cause. or something suspension or steering related. Even uneven wear on tires can cause this. but uneven wear is the sign of another problem, tracing back to suspension or steering problems.

1989 Mercury... | Answered on Oct 29, 2013

dash and tail sre tied together, so chk tail light fuse.

1989 Mercury... | Answered on Sep 06, 2013

Are you looking for a wiring diagram or a head light switch with a vacuum diaphragm to operate the light covers or to bring up your lights when you turn them on,like a corvette,if like a corvette,I had a 1971 corvette that didn't open and I used the vacuum parts on the light switch off of a 1968 Pontiac GTO,the light switch was the same as the corvette

1989 Mercury... | Answered on May 20, 2013

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