Idle Issue?

[LeviMM]

Greetings
So I am having idle issues with my '87 Grand Marquis. First I had a cracked fuel injector so I replaced it with a buddy of mine. The car started and drove fine before it, and it started and drove fine the first time after replacing it. But as I tried to start the car afterwards, it would turn over but wouldn't keep an idle. I tried it again while giving it some gas and it held an idle after I gently gave it gas for about 45 seconds or so. I drove it home, and as I was pulling into my driveway coming up the hill, it idled out again and I had to basically start it while giving it gas and shifting and giving it gas. Any suggestions on what my problem may be? As always thanks guys!

[EaOutlaw1969]

I would start by looking for a vacuum line that may have cracked or fallen off during or after the injector replacement. if you have old brittle vac lines replace them all.

[gadget73]

the line to the MAP sensor is very prone to failing, and it will run absolutely awful if that happens.

[LeviMM]

Thanks for the input. For the rooks(me), where's the MAP sensor?

[Tiggie]

Thanks for the input. For the rooks(me), where's the MAP sensor?

Basically on the firewall above the passenger valve cover. Black with wiring harness and single vacuum line going to it.



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[LeviMM]

Excellent help guys! So here's an update. I went to turn it on today and it started fine. I let it idle for awhile and it was running good other than the periodical surge idle. After letting it idle for awhile, I tried to chnage in to reverse and it turned off. It's something i've dealt with for awhile. What causes that? It started back up again fine. And I let it idle again for awhile. The tailpipes were dripping water which is a good sign, right? It has been sitting with gas in the tank for about 3 or so months. I checked the MAP sensor and it was connected but i did notice a red vaccuum line near the EGR not connected.(See the picture) Where should it be going? Also does the vacuum line with the silver cap be hanging out as such? (See picture)

Another issue i'm having as well once it gets up to temp around 195 degrees and the thermostat opens up, antifreeze starts leaking/spraying out somewhere. I can smell it burning on the valve cover and droplets are on the hoses around the rear of the driver's side valve cover near the IAC. What do you think is the culprit?

Thanks again guys!

[87GrandMarq]

Is your idle adjusted correctly? Do you still have your smog pump? Im pretty sure a few of those vacuum lines are supposed to go to the smog pump.


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[Kodachrome Wolf]

The red line should go to the vacuum tree at the back of the upper intake. It feeds the vacuum supply for the EGR, TAB, and TAD solenoids.

[sly]

The coolant leak is probably the EGR cooler lines. There's 2 small diameter hoses that go to the spacer behind the throttle body. The leak is probably from the short one that goes from the spacer to a nipple down near the back of the intake manifold. Can't remember if it's on the manifold or the head, but it's in that area. Those are probably the most overlooked hoses on these cars.

[87GrandMarq]

It connects to the lower intake manifold but it rusts out so thats probably the issue like you said. The one on my intake I got from a mustang was rusted to pieces so I just said screw it and deleted the egr cooler lines.


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[Tiggie]

That silver thing in picture 2 looks a lot like a PCV valve. It should be into the back side of the lower intake, if it is the PCV valve.

[VicCrownVic]

...Also does the vacuum line with the silver cap be hanging out as such? (See picture)

That looks like a PCV valve, but that's not where you would normally find that.

The PCV should be on the back of the engine mounted in the lower intake. One hose going from the underside of the upper intake to the PCV.

2 things to ignore in the picture below:

• Our cars do not have a tee in the hose, it's just one hose.
• The upper intake in the picture is backwards, but the idea is the same on our cars.

[LeviMM]

Here's another update.. So i think i figured out the where the PCV valve connects to from the upper intake. It fit into the hole so i took that as a good sign. Is the arrow in the picture accurate for the PCV valve? Thanks for the picture VicCrownVic showing where it was located!

And next is this the MAP sensor mentioned earlier? Do you all see any issues with it? The hose felt good when I checked it.

Also are these the hoses for the EGR cooler lines? What's the process for the delete? Is it a simple plugging the end of the line? I probably should search the forum for more info. Thanks again guys.

[sly]

yes. big hole in the rear of the lower intake is where the PCV lives.

"looks fine" but it may still have issues. Unplug the electrical connector to the MAP sensor. If the engine runs the same or better, it's bad. If the engine runs worse, it's fine.

And yes, that's the EGR cooler lines.

[LeviMM]

Thanks, Sly. I'll try that. Where does the MAP hose connect to?