Need help with 1987 5.0 in Town Car

[86VickyLX]

^why would the lines suck air if the fuel pump is in the gas tank?lol but, your right. its not a bad idea to check the fuel system and fuel filter.

Try drinking through a straw with holes towards the top, you're gonna suck air. though you should be smelling fuel I'd think.

[marquisman]

leaking fuel is different. i understand the sucking air part if its carbed/manual fuel pump at the engine. this happened with my dads wagon

[86VickyLX]

leaking fuel is different. i understand the sucking air part if its carbed/manual fuel pump at the engine. this happened with my dads wagon

Well what I was getting at, if there was a hole in the fuel line on the limo, I'd expect to smell fuel leaking.

[marquisman]

agreed!

[jubylives]

All good points. I checked the fuel lines already and checked the fuel pressure. 39 with engine of ignition on and 30 with engine running. That's where the haynes book said I should be. It never changes from 30 even when the car is acting up. I took a break from the car as I almost threw my back out leaning over this fool thing for over 8 hours. I imagine it's the idle thingy or something obvious and simple I just can't see it. If this thing was carbuerated I'd change the accerlerator pump diaphram. That's what it acts like.

[91waggin]

Ok, you're saying that it will stumble on throttle tip-in, but it will idle fine? Then it's probably not the idle air control. All that does is allow air to bypass the throttle plate so that the engine won't stall with the throttle closed.

Your description of it acting like it needs the accelerator pump repaired is very telling. It means the mixture is wrong, and further evidence of this is the gassy smell.

I'm assuming what you describe as a "gassy smell" is a rich-smelling exhaust, rather than the smell of raw fuel. Correct?

Since the problem happens on tip-in, double- and triple-check your throttle position sensor. Testing details can be found here:

http://fordfuelinjection.com/?p=30

If you've got an analog voltmeter, use it while you test it to make sure there are no dead spots that a digital one will hide.

Double-check the resistance values on your Engine coolant temp sensor (ECT). Info here:

http://fordfuelinjection.com/index.php?p=28

Check the condition of your ACT (Air charge temp sensor). Info here:

http://fordfuelinjection.com/index.php?p=29

The manifold absolute pressure sensor (MAP) is a sensor with a vacuum hose hooked up to it that measures intake manifold vacuum. This sensor is crucial for the computer to provide the appropriate mixture. Unfortunately they can't be easily tested, but grab a few from the junkyard and you should be able to find a good one.

Check the condition of all vacuum hoses, especially the one going to the MAP. It lives under the upper intake and has a hard life. It can collapse on itself, which can fuck things up royally. Remember that many of the vacuum lines on these cars are hard plastic, and after 20+ years they get brittle and break, creating a vacuum leak. All of the plastic vacuum lines can be replaced with rubber hose, provided you make the right connections.

It will help a great deal if you check all of the above things before continuing, since it will allow us to take a great deal of variables out of the equation.

Cheers and good luck!

[gadget73]

you know, I have seen bad MAP sensors cause this sort of thing. If the vacuum line to the sensor is fine, try unhooking it and see if anything changes. If it doesn't, or if it runs better, the MAP is probably shot. For whatever wierd reason, a bad MAP sensor when connected to vacuum runs like a good MAP does when it has no vacuum. Even wierder, a bad MAP with no vacuum runs like a good one with vacuum.

[jubylives]

Oh wow. Thanks for the posts so far. Super helpful. I will go through that on my next days off. I was looking at that temp sensor as it is only $11 then I saw the hex head was brass and stopped there. Probably take the T it is connected off then vise grip it off. Looks like it will be easier to take out the distributor to get moving room. I'll post what happens after that. thanks

[87gtVIC]

Pita taking the temp sensor out. Always likes to round the edges. Crappy soft metal.

[91waggin]

Just to be clear, make sure you're getting a new ECT sensor and not the one that runs the idiot light or the gauge. The idiot light one has a single wire connector, while the one for the engine computer has more than one.

[jubylives]

Just to be clear, make sure you're getting a new ECT sensor and not the one that runs the idiot light or the gauge. The idiot light one has a single wire connector, while the one for the engine computer has more than one.

Oh yea. I had a heck of a time convincing the tard as Oreilys that there was two. He argue with me bout it. I gotta stop going there. It's just closer then the rest.

[gadget73]

all the time I have people argue with me about what parts my car does and does not have. Its quite frustrating. There are reasons I shop online whenever I can.

[91waggin]

i usually go online to oreillys or whatever, get a part #, and take that in with me. That way they don't even ask about application.

[johnunit]

"that thing didn't come with a 5.8, you're thinking 3.8. it came with a 3.8 or 5.0 if it was LX"
This AFTER I specified "full size" repeatedly, and pointing to the car parked out front. Parts store goons are ridiculous sometimes.

[91waggin]

*snort*