Cadillac DeVille

My first reaction is that water or dirt in the fuel would cause a car to backfire and sputter.

It is a symptom that indicates the car is not getting enough fuel. You may have gotten some bad gas.

Easiest fix, pour some STP gas treatment in the tank to absorb any extra condensation or water and drive the car to use up the gas.

When you're down to less than half a tank, fill the tank with new gas at a reputable high volume gas station. If you see an improvement, just keep driving and add new gas when you can. The situation will probably clear up on it's own after a couple tankfuls.

In extreme cases, the bad fuel could be drained and the fuel filter could be replaced. On most GM cars the external fuel filter is usually pretty cheap -- like under $40 and is located just in front of the back wheels near a frame rail. The labor is pretty minimal too. It's like a ten minute job for most mechanics. Not sure about the specifics of your 94 Cadillac though.

Also, there is also usually a filter like sock inside the gas tank, where the fuel pump is.

If that is clogged up, or if the fuel pump is going bad, you might be looking at a lot of money for repairs. (Hundreds of dollars)

Tip: Never let your gas tank go lower than half a tank. The gasoline in the tank actually helps cool the electric fuel pump and prevent it from overheating and wearing out.

One other possibility is that you may have a bad spark -- spark plugs overdue, distributor cap might be cracked, (crack is really hard to see, doesn't look like an actual crack but more like a dark, fine human hair on the inside of the distributor cap) or rotor worn out....something related to that.

These are all typical replacement items that should be serviced from time to time.

At some point GM stopped using typical Distributor caps... not sure if your 94 has one.

My 92 Caddy does.

All in all, I'm betting you just got a big batch of bad gasoline (dirt or water in it) somewhere, and I wouldn't buy gas there again...at least for a while. Good luck.

There are four heated oxygen sensors on the 1996 and up NorthStars. One in each exhaust manifold, and just before and after the catalytic converter. The sensor in the right side exhaust manifold is the hardest to see and service, it's behind the engine up against the bulkhead. If the engine has an AIR system that also helps keep it hidden.

Its a simple screw in kind. The tips of the sensors are delicate so do net bang them around or get them dirty. There's usually a 1 way plug for a multy wire or a crimp for single wire sensor.

What is the P39 code for a 1994 Cadillac with a northstar motor

Maybe, Hot weather kills batteries. In cold weather a battery that has a low state of charge can freeze and be damaged. Cold weather makes the power required to start the engine increase dramatically so a battery in a low state of charge cannot deliver the amps required to start the unit. When I lived in New Jersey I used a battery charger on the battery at low amps (cheap Sears charger) overnight in the fall to make sure the battery was fully charged at the onset of cold weather. Late in December I'd top it up again. At the same time make sure the alternator belt is tight enough. With engine off and cold grab the alternator fa/pulley and try to turn it. If it spins/slips on the belt without turning over the engine it's too loose and a full battery will become a low battery. This technique was easy and way cheaper than a stalled car call in a blizzard.

On the distributor cap

take of the door panel and apply power and ground to the motor only takes about 10 minutes to get the panel on and off.

Its not your fuel Pump that shows this its your sending unit which is attached to the fuel pump and located in the Gas tank. It could be a couple of things. One the float in the tank is stuck,the sending unit is defective or the wiring is loose or disconnected. Best way to test is to remove it from the tank. This will require removing the tank. If you cant do this take it to a garage.

at the bottom of the fan, between the two fans

faulty blower module. Under hood not far from blower motor

The cabin air filter on a 1991 Cadillac DeVille is located under and slightly behind the glove compartment. All the air which enters the cabin is filtered through it to remove most contaminants.

If your STS is like mine, the battery is under the rear seat. You can pull up on the rear seat and expose the battery, at which point, you can attach jumper cables.

Don't do that.There is a plus(+) terminal under the hood.Just hook up the jumper cable to this terminal and minus(-) to the metal part(ground) and you are all set.

If it's the base Sedan Deville with the 4.9 liter, it's 5 quarts with the filter. For the Deville Concours with the Northstar, it's 7.5 quarts with the filter.

bad master cylinder calipers rubber caliper hose and if you have raer drum brakes and the rears are locking the brake shoe are wet from the wheel cyls and you are in grave danger

Either the inside of the rad is plugged, so you need to flush it, or the vanes are plugged with dirt, bugs, leaves, etc. You will need to pressure wash it from the inside of the engine compartment. Your water pump could be shot.

if it is a hand pull E-brake, pull it up slightly, push in the button and let it down. if it is a foot E-brake look down near the foot pedal for it and there should be a pull cable. pull it and it will disenguage.

I own a 1998 Deville D'Elegance and had my Drivers Side power window motor go out, upon removing the door panel (the screws are hidden) I encountered a large metal plate covering the entire door, there didn't appear to be an easy way to remove it without disconnecting the side airbag and other items such as the door handle so I took it to my local Chevy dealer (after calling the Cadillac dealer for a quote) and had the motor, master window switch (the one in the drivers door that operates all 4 windows) and labor done for around $500. This is in NW Florida and was about a year ago.

Pretty easy job, there are a few videos on youtube that show how it's done. Just did both mine on my 1994 Deville and one on my 2004 Seville. It is almost a must to have a compressor and impact gun but can be done without. Hardest part I had was making sure the axle was unstuck from the hub, had to back the nut off and then hit the axle end with a soft faced hammer, rawhide or plastic faced. The Deville was easier because the bolts are on the front of the hub where they're on the back on the Seville. You have to have both front wheels off the ground to do this because you have to spin the axle to get to the bolts, they only come out through one of the holes.

What is the firing order of a 4.9 lirte 1994 Cadillac Sedan Deville

(6) Removal and Installation of Cowl Heater Core Assembly (60, 62 & 7S Left Side) 1. Drain cooling system. 2. Remove left front fender dust shield. 3. Remove four fender to body mounting screws and block fender out from body about one or two inches to permit access to heater attaching screws. 4. Remove rubber heater-unit-to-blower-unit duct under fender. 5. Remove heater unit to blower unit support bracket. 6. Remove control cables at control assembly on instrument panel. Refer to Note 3. 7. Remove three screws and remove kick pad heater grille. 8. Remove kick pad. 9. Remove two kick pad heater duct to heater unit screws. 10. Remove two defroster hose clamps and hoses at heater case. 11. Remove clamp and remove heater air hose at heater case. 12. Disconnect water hoses from txmom of heater assembly. 13. Remove four hearer-unit-to-cowl retaining screws. 14. Remove heater unit. b. Inslallation 1. To install cowl heater core assembly, reverse above procedure.

On the 1993 Cadillac 4.9L the soleniod is located atop the starter.The starter is afixed directlyto the side of the motor at the front of the car behind the radiator.

I have a 90 Coupe DeVille and I the digital readout said 1 gallon and i put a little more than 15 gallons in, but i dont know how accurate it is. Answer The 90 Cadillac DeVille holds 18 gallons of premium fuel. I have found the digital fuel monitor system to be very accurate within a tenth of a gallon most of the time but it will read F (full) anywhere above 15 gallons.

If there is no diagram under the hood, I would have drawn a diagram before the belt was removed. Just saying.

change backup light 2002 cadillac deville

unpluge & repluge the negative terminal of yr battery.