velorossa22

I have a 1999 Crown Vic nonpolice that has a hesistation problem. It only seems to do it in overdrive and between about 40 mph to 50 mph. It just seems to "bump" like it missed once or twice then maybe two seconds later do it again. When I give it more throttle it goes away. It used to do this thing once in awhile where suddenly it'd start missing really bad like it's on 6 cylinders and it wouldn't be able to accelerate. So i'd stop the car and turn it off and as soon as I turned it back on it'd be back to normal. So far I've changed the fuel filter and put fuel injection cleaner in the tank to no avail. I've tried 92 octane too and that hasn't made a difference. Has anyone run into this problem with your car? I'm not sure that those two problems are related but I think they are.
Also the automatic climate control only blows hot air no matter what temp you set it on. It used to work like it should but then one day it only blew hot air no matter what I did, even if I unplugged the climate control module. ANy ideas?
ANd lastly the windshield wipers only work on the fast mode. They won't work on any other setting, which is kinda annoying. I'm thinking that in this case the switch may have gone bad.
I love the car I just wish it worked perfectly. Any input from you guys I'd really appreciate it.

Rocky Bennett

Welcome to the forum. How many miles are on the car? If it has more than 40,000 miles on it you might just need to go to the Ford dealer and have your fuel injection system purged. It costs about $200 but it really makes a big difference.

velorossa22

Yeah the car has 142000 on the odo. What exactly do they do on a fuel system purge? I've never heard of it, but then maybe I live in a cave.

Rocky Bennett

When I first bought my Contour I took it down to the ford dealer for a complete service, the car already had 40,000 miles on it so I figured it could certainly use some service. I really don't know what they do, I hope somebody else will chime in, but it was one of the things that the maintanence manager highly recommended, and it sure made a big difference. I will be doing it with my Grand Marquis that I just bought. The car only has 15,000 miles on it but since it only was driven on average of 125 miles a month since it was new the Ford dealer has told me that a fuel sysytem purge will make a night and day difference to the performance. I will not have this job done there, the local Dodge dealer is currently running a special and is doing this job for $189, which I feel is a good deal.

Rocky Bennett

OK, I just did a little research. The original owners manual of my Grand Marquis (2000 with a 4.6) indicates that at 30,000 ,iles and 60,000 miles and so-forth, the fuel filter is to be changed. Talked to my mechanic on the phone just now and when they change the fuel filter they have the oppurtunity to go in and clean out all the lines and other parts of the fuel delivery system, this is called purging. It takes a shop about 4 hours of labor plus the cost of the filter. It really makes a difference.

sheebeehuh

At first pass, it doesn't sound like a fuel problem to me. Does your car have COPS (Coil-On-Plugs)? One of them could be going bad. Have you checked to see if their any diagnostic codes?

As for your windshield wipers, the switch is the most likely problem. It's a common failure item.

Your A/C problem sounds like a diverter door problem. There should be some other posts on this forum to help you diagnose that. Do a search.

velorossa22

I've never heard of Coil on plug. What is that? How do I test to see if that's the problem? That could be a problem. I have a haynes manual and it is totally worthless.
So the problem with the wipers is the motor. I tested with a friends switch and it has the same problem.

sheebeehuh

Coil On Plug (COPS) is when each spark plug has it's own coil. Ford went to that setup at some point after '97 (my '97 Grand Marquis has 2, 4-point coil packs mounted just ahead of each head). Newer models have COPS units near each plug (8). These COPS modules are problematic for many people and when one fails you often need to replace them all (as they tend to fail in succession causing you to chase you tail).

As for your wipers, I doubt it's the motor if it works fine on HI. In older cars there is a resistor panel that controls the lower speeds of the wipers. When it burns out wipers only work on hi. I'm not sure about what kind of speed control circuit your car uses but if it's something similar then that could be the problem.

velorossa22

huh,
I'm starting to see what you're talking about. I had a 95 vic that had 2 distributor caps 8 wires and 8 plugs. I'm looking at my 99 vic and I can't find spark plugs, wires or anything else. WTF?!? I defianetly need to learn more about the COPS thing. So if each plug has it's own coil where the heck are they? Obviously they look different than what I'm used to. And how much do they cost the replace? I'm getting the feeling they're kinda spendy, so is there a way to check them before replacing? I hate spending lotsa money on something just to find out it wasn't it.
Anyways I really appreciate you helping me out on that one.

sheebeehuh

The plugs are on "top" of the engine and go into the heads vertically. The COPS modules sit on top of the plugs; there are 4 on either side of the intake manifold. As such, you don't have plug wires on the normal sense.

There are some pics here ...

Ford / Lincoln / Mercury 4.6L Intake Manifold Repair

of a non-COPS engine ('07 model) that at least show you where the plugs are located. You can probably do a seach of this forum (or others) and find info on how to test the COPS units. I am told by many that when one goes you should replace them all. If you don't you'll be kicking yourself becuase they tend to go out in sequence when on fails (or so I hear).