Can't go uphill

We have a 1985 Ford Crown Victoria Station Wagon. The car runs ok except going up hill. When going up hill the car bucks and misses. A complete tune up of both the ignition and fuel system was done yet the problem is still there.

Anyone have any ideas? Brian our mechanic is out of ideas of his own.

Start shopping for a new fuel pump. However have the pump pressure checked before you ask for it to be replaced. It is also possible that you have a blocked fuel filter (when was the last time you replaced it?). If it has been a while and you need to replace the pump, do the filter at the same time. Not replacing the filter as recommended can cause the pump problem.

classic fuel pump failing…

I might add, just to “save face for Brian,” that my mechanic missed the same problem with the same symptoms, because when tested in the shop, the pump seemed ok…or so he said.

The fuel pump and filter were replaced. Brian had the opinion it was in the fuel system after the tune up didn’t clear the problem. Does the throttle body need replaced?

There’s a couple of possibilities but it needs to be known which engine you have. Most (5.0) were fuel injected and a few were carbureted; and others (5.4) were carbureted. Knowing which you have narrows the possibilities way down.

Throttle body? I thought Ford did not put EFI on these cars until 1987. It should have a carb, and it sounds like it is gummed up, ready for a rebuild. Replacing the throttle body won’t do much good. Check for vacuum leaks. Also, check the TPS and MAP sensors. They may not be sending consistent signals.

The engine is a 302 and is not equipped with a carbruator. On level ground the bucking and missing dosen’t happen. Even on the freeway at 70 mph there is no missing or bucking only on an uphill pull.
My thought was the emmission system. New catalitic converters were installed about a year and a half ago.

On a car that old (get rid of it) the computer is solid state and may be out to lunch. The junkyards have stacks of them so get your old one out and see if you can find one. Don’t do it yet. Thry may be able to get a match on it and sell you the right one. Save the prom chip if so equipped.

SEFI injection was used on some 1986 models because I have an '86 Mustang GT engine. A quick look at the book shows that CFI should be used on this car (throttle body) and that 5.8 engines through '88 were carburetor equipped with the VV carb.

One of my first thoughts was a partially clogged converter but since that’s been replaced that guess is history.

Just pondering if this problem could be caused by ignition timing; as in too much retard. Ford started using the TFI-IV system in 1984 and depending on the model and emissions category (Federal or California) the car could possibly have been outfitted with the Dura Spark III.
I strongly think (key word) that your car has the TFI-IV setup. This can be easily identified by a little gray module mounted on the side of the distributor. The modules were prone to failure but normally they do not cause the symptoms that your car has.

It is very critical when checking and setting the timing on these cars that the SPOUT connector be unplugged. Failure to do so will cause the timing to be retarded quite a bit (8-10 degrees) and while the car may appear to run at least ok it’s quite possible for retarded timing (depending on the degree of course) to cause a car to start falling flat on an upgrade.
Incorrectly setting the timing is not that rare a thing to happen as many people may connect a timing light, see the mark well advanced, and back the distributor off in an attempt to bring the timing mark back where it should be. Of course, failure to disconnect that SPOUT connector before doing this makes the whole exercise useless.

Hope that helps anyway.

Yes the car is 23 years old but it is in excellent shape. It has never been hit and is in almost mint condition. The plan is to keep it as a classic car.
I’ve had the car for 18 years buying it from the original owner when it was about four years old.
Just need to find the uphill problem.
I don’t know if photos can be put up on here otherwise I would do it. My avatar has a small photo taken about a year and a half ago of the car.

Always a dispute with good advice right in front of you. You are not alone in the resistance movement. Lets just say that you are doing it for reasons of your own. If you really want to keep it forever, when do you do a restoration? If you want reliability; your chances improve without that model of car. Lucky that there are parts available. Things deteriorate in places you can’t even imagine. If it were a 1976 Impala, you would be on the low-tech side and could guaranty being able to run that bomb forever. 85 is kind of a transition year for technology and underdash complication…

The distributer does have a grey box on the side of it. Just replaced it about three weeks ago when it quit. That little box is important as the car just shut down instantly when it quit.
The uphill problem is still there as of this morning.

Those TFI-IV modules were prone to failure and the cause of a class action suit against FOMOCO.
This gets back to what I said in my previous post about ignition timing. On a lot of models the module is difficult or impossible to change unless the distributor is removed or rotated and if someone does not check and reset the timing properly after changing this module it could very well cause the problem you’re having.

Found the problem finally. Turned out to be a sensor on the throttle body that acts like a choke on a carbeurator. The sensor went south but it didn’t show up on any scan system. Also a NAPA MAP Sensor was used. The map sensor although supposed to be for the year and model of my car wasn’t compatable. A FORD MAP sensor and a new sensor for the throttlebody cured the uphill problem
Thanks for all the replies