A Grand Marquis far from home - Life with my 1988 Mercury Grand Marquis GS

[Mainemantom]

When adjusting the shift indicator, block the wheels FIRST. Put the lever into neutral. You can fine tune the adjustment by slightly moving the white collar and aligning / centering the indicator with the "N" Expect the collar to be broken. As others have suggested using a hose clamp or zip tie can make the collar tight.

[DerekTheGreat]

More wrenching this weekend! I'm finally feeling like I'm making progress, slowly being able to tackle quality-of-life issues rather than existential mechanical ones. The first order of business was the Idle Air Control (IAC) thing, which I took apart and cleaned as thoroughly as I could... ...I noticed that when I tried the car afterwards, it ran fine but when I put the throttle to the floor it paused for a second, almost as if it tried to take a deep breath before then revving up. This happened both in Park and under load. The car is fine to drive but I'm wondering what might cause it. Some sort of self-calibration that needs to be made? I didn't unplug the battery so maybe that has something to do with it?

While on that, I noticed these two hoses that looked really tired. They look almost like water hoses, but it can't be water running up to the throttle body. Does anyone know what these are? Vacuum?...

I'd certainly start by disconnecting the battery and reconnecting it. However, the hesitation could be caused by the EGR valve opening too much on initial throttle tip-in. If the problem still persists after the battery shuffle, trace the green vacuum line going to the EGR valve back to the passenger side fender liner. Pop the plastic cap off the solenoid deal which controls EGR operation, remove what's left of the foam filter and snort some WD-40 in there. Might help clear it up. That is of course if your EGR is functioning at all. You can test that with a hand-held vacuum pump. If the engine starts to stumble as you pull vacuum on the valve, it's working.

Two other things to look at would be the Intake Air Temperature Sensor on the driver's side lower intake manifold and the MAP sensor- specifically the vacuum hose feeding it. Make sure all that stuff is as the factory intended. The IAT probably needs to be replaced. It does in my car, causes it to sometimes stall when restarted hot.

Those hoses going to the EGR spacer are indeed for coolant. They are there for several reasons. One may be to prevent throttle icing (seeing as these are port fuel injected, I don't see how that's a problem) and the other may be just to keep temperature in moderation during highway cruise. I imagine when the EGR is flowing, stuff can get mighty hot.

[Tynnerstroem]

Thank you all very much for your input. Curiously, regarding the parking brake the car already has a release handle, and it looks factory enough so maybe some previous owner was one step ahead of me. The system has been plugged for now so at least there’s no more hissing, although I’d like to get it functional again some day. We shall see.

With regards to those two coolant hoses going to the EGR spacer, I can’t seem to find those on RockAuto, so I suppose I’ll make those myself out of whatever hosing I can find. Is there something about that I’d need to keep in mind? Do coolant hoses require some special sort of material or marking or something, like fuel lines do?

I did name this thread ”Life with”, and since I’ve now started actually living with the car here is a slice of life image from this morning’s commute. One thing I do miss from my 1996 Roadmaster is the cup holder.

[Tiggie]

The EGR cooler is 1/4 coolant hose. My local parts stores don't carry it. RockAuto has it. It's different from vacuum or fuel hose. Fuel hose works in a pinch but the right hose material is best if you can find it. https://www.rockauto.com/en/parts/ga...e+/+pipe,11564

[VicCrownVic]

The EGR cooler is 1/4 coolant hose. My local parts stores don't carry it. RockAuto has it. It's different from vacuum or fuel hose. Fuel hose works in a pinch but the right hose material is best if you can find it. https://www.rockauto.com/en/parts/ga...e+/+pipe,11564

^This. Something about the chemistry between the coolant and the hose material is the reason you want coolant specific hose. Bulk hose is the only option. It's been a while since I've touched those hoses, but I think I bought about 3feet or roughly 1m of hose to be sure I would have enough for both hoses. It's also a bit of a pain to get at the lower connections for those hoses.

[Tynnerstroem]

Thanks very much gentlemen! I'll run by a parts store here today, no need paying shipping and customs if it's not some special, ready-made stuff for the car.

I mentioned earlier that I've managed to get to quality-of-life issues with the car now which is a relief and a half. Today I'm going to pull at least one of the door panels in the front to figure out what is rattling and why the door locks aren't working. Like several of you have suggested in this thread, more likely than not it's the actuators. However since I believe people have been tearing into this car before I'd like to just try to make sure.

Another QoL-issue that is massive to me is the cruise control. It's something I just can't live without, especially since my commute is freeways all the way. I've tried reading around here on the forums a bit and it seems like there could be some differences between the years (whether the function is integrated into the car's computer or something like that). I know there's a troubleshooting guide in the shop manual, but is there any culprit that's more likely than any other? Can I check the function of the cruise servo using a handheld vacuum pump? Any good lessons learned with the cruise on 1988's that anyone can share?

[Arquemann]

If the cruise dump valve that's tied to the brake pedal is leaky or adjusted wrong, the cruise won't build vacuum and won't work. You can check the vacuum line going from the cruise servo down into the cabin, if it holds vacuum, it's fine.
Atleast on my '85 the cruise is a standalone system. If your ecm under the dash has another sizeable module to the side, it's most likely the standalone cruise module.
It could also be the cruise buttons causing problems, after I fixed my cruise, it often took more than one press to active. Switches get crusty over time if unused. Though if and when you do get your cruise working, do note that it's not like the modern electronic units. After setting the cruise it will take a second or two for the vacuum servo to catch up, so don't lift off the throttle right after pressing set. You can feel it on the pedal when the cruise takes control.

On the door rattle, have you checked the striker bushings yet? Could also be the lock and handle actuator rods.

[Tynnerstroem]

Thanks! It has occurred to me to remove the steering wheel just to look at how those switches look under there. Might try that today if time allows for it. Anything to know when doing that?

With the striker bushings, what exactly do we mean by that? This might be where English being my second language shows its weakness but is it where the door latches on to the body when the door closes? On this 1990 Grand Marquis, is it the beige part of that black thing the door latches onto? Is there any difference between the model years that I should be aware of here?
Another thing I remember just now is that my opera lamps are working so-so. They light up, then only half of them light up, and then they don't light up at all and then they might flicker a little bit. Is it easy to just pop the covers off and change the lamps under there? Or do they run on some special lamps that can't be purchased anymore?

[Arquemann]

You'll need a puller tool for the steering wheel. Might use metric bolts, not sure. The backside of the wheel is screwed on and they hold the switches too.

Those beige things in the pic is exactly that, the striker bushings.

Normal opera lights just use a regular small bulb, which is in the middle. It won't light up the entire lens unless it's totally dark outside. You can get at the bulb and socket by removing the B-pillar interior trim, just 4 screws and move it to the side with the seat belt. Though some Panthers have electroluminescent lights in the opera lights, I haven't the faintest clue how to deal with those.

[Tynnerstroem]

Thanks as always for your input. Without this forum this 30 year old corporate dude would've probably had mechanics bills deep enough to drown in, or worse - would've had to drive a boring car. Life's too short for that.

Tearing into the doors was one of those one step forward, two steps back kind of things. This is how the actuator was mounted on the passenger side. No wonder it didn't work.


At the same time, I've been having this issue with the key lock on the passenger side, where the key just spins around when you turn it. No wonder:


Behind the door panel on the drivers side, it was fairly obvious why the power locks weren't working - there was no motor!


It is when I see shit like this that I start dreaming about just accepting an electric company car. I have no issue with working on and troubleshooting things that are old and malfunctioning, but when you have to account for other people's incompetence it gets really frustrating. However I suppose it's not all bad, since this showed me pretty clearly why:

1. The power locks weren't working in the front.
2. Why both doors rattle really bad when closed

I have ordered the actuators and some other stuff from RockAuto and it should arrive on Monday.

A thought I had on the cruise control, that I was hoping to check with you guys - so since I plugged the vacuum release for the parking brake, there's no hissing. No hissing, EXCEPT for when I depress the brake pedal all the way to shift in and out of gears (or at a stoplight, if I lean heavily on the pedal). Could that hissing be due to that vacuum dump valve for the cruise control that was mentioned earlier?

[DerekTheGreat]

And you thought the bum-fuckery was bad with your Roadmaster.

Well, you're building a history with the car and that's a good thing. At the same time, you're improving your technical know-how. All good stuff. Continue to say "no" to modern vehicles.

[GM_Guy]

Things that happen when people don't take the time to figure out the why and hows before brute forcing something.

[Tynnerstroem]

Was going to take it to my mechanic for a whole host of things that require a lift, which I don’t feel like doing lying on my dads gravel driveway. Lo and behold - battery was drained! I’ve asked my guy to run a check on it, hopefully it’s just the battery that died because of the cold weather that’s arrived. Now all I have to do is wait for it to be finished, and then, hopefully, the real driving part of owning this thing can start.

[DerekTheGreat]

I like those T-Birds, especially with a 5.0.

[Tynnerstroem]

DerekTheGreat that makes two of us! That was the car I drove during my university years, but since then my dad has sort of inherited the car. It only has 99k miles and runs super great still.

It is to my great relief that I announce the car is back in my hands! You'll recall that I sold the Roadmaster almost a month ago to the day, and what a long month it was being without a car.


Reflections from taking it home:

• The cruise control is really high upon the list of stuff getting fixed ASAP. I've been researching here on the forums and have a pretty good idea of where to start.
• The auto lamp function suddenly does not work, but worked when I left the car. It has gotten a new battery since but that shouldn't be affecting it. I remember seeing the light sensor on RockAuto in the past, but now I can't find it. After some googling, I find a part called "Sentinel sensor" - is that the part on the dash that senses how bright or dark it is outside?
• The interior courtesy lights work, but also kind of don't. Opening the drivers door sometimes turns them on, sometimes does not. Turning the dimmer switch now in the garage did not turn them on, but I did notice that the courtesy lights turned on when I lifted the door handle to check that I had locked the door. Any theories as to what might be afoot here?
• Transmission kind of shifts better now after the fluid change, but maybe it's placebo. Will commute with it for a few days now so we'll see.
• I'm wondering if the fuel gauge is funky. When I picked it up the fuel lamp was on, which turns on when there's like 10% of fuel left right? It's my understanding that these have 18,5 gallon tanks, which should mean that it would've had like 1,85 gallons left. But as much as I tried at the gas station I could only get 14 gallons into it - a discrepancy of 2,35 gallons. What might this be? The sender unit in the tank packing it up?

As soon as we get temperatures above freezing again I'm doing the front brakes and wheel bearings. There's a vibration when braking but since I didn't feel it in the steering wheel I thought the drums were bad, but my guy measured the discs and they're warped from the calipers being tired. Discs for $14 from RockAuto! Not to mention the calipers that were practically free as well. I know I sound like a broken record but I can't get over how cheap the parts are. Still it feels great finally having the car back, to finally actually get to drive it! Celebrating with a commute to work tomorrow.