Gas Gauge Acts Crazy

Gas Gauge Not Performing right

Jeep Grand Cherokee, Nut'zy Gas Gauge

Q: The gas gauge on 1997 Jeep Grand Cherokee will drop to empty then return to 3/4 to 1/2 tank every so often or until I fill it up or the gauge goes below half tank. The dealer said I need a new pump but there isn't anything else going on. Any suggestions?

- Salvatore T.

A: Your vehicle is notorious for gas gauge problems. In fact, there was a safety recall that affected about 400,000 Jeeps including the Jeep Grand Cherokee built in ‘97. The problem was the gas gauge would report that there was enough fuel when, in reality, there was not enough fuel and the vehicle would be dead on the side of the road. I’m not sure that your Jeep qualifies for this recall but it is worth checking into. Also, you’re not being told the whole story. If your Jeep dealer checks his/her Technical Service Bulletins (TSBs) they will find TSB# 08-19-97 that provides the part number for a replacement fuel sending unit that is sold separately. The TSB goes on to identify which of the 3 possible replacement part numbers that would fit your Jeep. The gas tank still has to be removed to service this part, but it is at a considerable savings to the vehicle owner compared to buying the complete fuel pump module. The fuel pump module is a new fuel pump and sending unit all together and is a bit on the pricey side. One last note, if your fuel pump has 100k and has not be replaced I would suggest installing the complete module. About any fuel pump with that kind of mileage is living on borrowed time.

Brakes are ratcheting and makes clicking sound

Brake Ratchet and Makes Clicking noise

Q: I changed the ball joints on 1997 Jeep Grand Cherokee 4 wheel drive. After that  brakes act strange. It seems my ABS is acting up and I hear a clicking sound as I increase in speed.When I apply the brakes it sounds like my brakes are ratcheting.


A: Take a look at the front axles of your jeep just where they enter the hub assembly. You should see a part that looks like a gear that is mounted on the axle. That gear is called a toner ring. As the teeth/gear looking part of the toner ring pass by the wheel speed sensor, a signal is created that the ABS system uses to monitor wheel speed. If a tooth is broken off the gear, the ABS computer will think that the wheel is turning at a different speed. This will cause the ABS computer to become active when it doesn't have to be. It doesn't take much to mess up the toner ring or even the sensor. I would suggest a close inspection of these components on both sides of the vehicle for possible damage. Any signs of damage will require replacement of the sensor, or if the toner ring is damaged the axle will have to be replaced. The toner ring is not sold separately.

Squeaking Brakes

Jeep Cherokee Brake Squeaks


Q: Brake job done on our 1996 Jeep Grand Cherokee back in April of 1998. A few weeks later I went back because the brakes were squealing. They said, "It's supposed to sound like that because there is no more asbestos in the brakes". They also said, "It will wear off after I run the car a while and put on a few miles". I recently took it back again in June of this year. Again they said, "Nothing is wrong, they are suppose to squeal". I asked them," How come the brakes don't squeal on the new cars in this lot?" No reply! My question to you. What do you think? Is there anything I can do about this?... Squeaking brakes!!!!!!!

A: Well, you've got them. The brakes are not supposed to squeal on your vehicle, but the noise doesn't mean the brakes are unsafe, there could be other factors. The squealing noise is an indication that not all the necessary procedures were followed while the brake job was being performed, or that the friction material used on the brakes was of questionable quality. The high frequency squealing sound, when braking, is caused by brake pads vibrating. Improper assembly procedures are the most common cause for brake squeal. Proper inspection, preparation, cleaning and lubrication of braking components is critical in preventing brake squeal. Also, realize that not all braking materials, brake pads or shoes, are created equal. Discount brake pads or shoes are not of the same quality engineering and material as original equipment or quality aftermarket brakes. It's like re-capped tires compared to radials tires. They both do the same job but...

Repetitive Brake Problems

Brake Issues Occur Again n Again on Jeep

Regarding Jeep Grand Cherokee, Brake Problems
Q: My vehicle is 97 Grand Cherokee with 55k miles. Wee just replaced 4th set of  brakes put on including the original set. The rotors and pads were replaced each time. That equals a new set approximately every 14k miles. It is driven in very mild conditions around town with no heavy braking. It always has the same problem. The brakes feel like they engage and disengage as you come to a stop. It gives a slow pulsing sensation.

The first evaluation always offered is warped rotors. The problem is that immediately after a brake job you still can feel this problem. It’s milder at first and then becomes more pronounced as time goes on. I also know it has nothing to do with the rear brakes because if you use the hand brake to stop you don’t get the symptom.

The second theory is some type of ABS malfunction.This has been completely dismissed by the dealer.

Any idea what the problem could be??

A: How about checking the hub that the brake rotors are mounted on? Just the day of answering your letter we a had a Mercury Crown Vic in the shop that had a brake pulsation complaint. Diagnosis indicated that the front brake rotors were the problem. From what we were told, they had been a problem for sometime. As often as possible we’ll machine the brake rotors on the vehicle. When the equipment was installed on the vehicle to machine the rotors there was a problem. The computer, yes we used computerized equipment to perform this task, was at a loss. It could not calibrate itself properly, meaning it needed help from a carbon based life form (humans). Inspection found that the hub that the brake rotor set on was off by .003" of an inch. Now .003" of an inch is just about 2 hairs stacked. That’s not much you may say. But, in the world of brakes that adds up to a lot when you carry that line out another 4 to 5". My point is that no matter how many brake rotors are installed on this vehicle the brakes will always end up pulsating,, which could very well be the problem with your vehicle. They just have to look deeper. As for the Crown Vic, there is no silicone based form (computer) that can problem solve the way the carbon forms do.

Evaporator Coil Replacement

 Replacement Evaporator Coil For Jeep Cherokee



Q: A query from inexperienced mechanic, I was wondering if I am able to replace the evaporator coil for 1996 Jeep Grand Cherokee with a 5.2 liter engine. Where can I find complete instructions on how to do it?
Please Help !!!!!!!!!!!!!


A: First, you would have to define inexperienced. I’m a believer that anyone can do about anything they put their mind to. The main tools you’ll need for a job such as replacing an A/C evaporator in your Jeep is patience, attention to detail and information. Information can be found but the detailed information you need, to maintain patience, will need to be borrowed or bought. You can purchase factory information and diagrams on-line. An example would be found at alldata.com. ALLDATA Information Systems has a Do It Yourself (DIY) section that allows you to purchase vehicle specific information. If you want to DIY this job, be organized. Have information and allow plenty of time. If you’re inexperienced, tackling a job like replacing an A/C evaporator without good information will have you throwing tools down the driveway. In which case, you should park your Jeep to allow for easy access for the wrecker, in the event you throw all your tools down the driveway.

Low Oil Pressure

Oil Pressure Very Low on Jeep Grand Cherokee

Q:My Vehicle is 1996 Jeep Grand Cherokee with a 5.2 liter engine and the oil pump failed on vacation. The mechanic replaced the main, rod bearings, seal and oil pump. Now when the engine is started cold the oil pressure is fine. After warming up the idling oil pressure is 20 PSI and drops to just above zero when placed into gear. When the Jeep is moving down the road, the oil pressure is 20-30 PSI.


A: I’m concerned a bit with your oil pressure readings. The first thing you should do is have a mechanical oil pressure gauge installed and check the readings to confirm that the dash display is accurate  If the mechanical reading is the same as the dash gauge readings then you have problems, and here is where I have a problem. Why were the rod and main bearings replaced? The likely answer is because they were damaged. If they were damaged what did the surface that they rode against look like? I’ll tell you right now, damaged! If an engine loses an oil pump and the main and rod bearings are damaged I can assure you that the surface (crankshaft) that they ride on was damaged as well. So now ask yourself what happens if you place new parts against damaged old parts? I’ll save you the time, you get low oil pressure. When the oil pump failed the rod and main bearings rode against the crankshaft main and rod journals with no lubrication. The bearings are the soft part, but the surface on the crankshaft went down with the bearings. If I’m wrong then you have bad camshaft bearings. In either case, the engine has to come out of the vehicle to repair it correctly. Or should I say pull the check book out to repair it correctly.

Cruise Control Not Working On Jeep

Jeep Cherokee Cruise Control Has No Power

Cruise Control Fuse Location

Q: Its a 1996 Jeep Grand Cherokee and I cannot find a fuse for the cruise control, and it seems to have no power to it. The light on the dash will not come up when the cruise control is activated. I have looked under the hood and on the passenger side door panel fuse holders, and the cruise control doesn't seem to be indicated in those two areas.


A: You’re not really going to find a fuse for the cruise control on your Jeep. Why? The cruise control unit is controlled by the vehicle computer and receives its power supply from the same computer. If power is not being supplied to the speed control servo you want to inspect the stop light switch. The stop light switch, on your vehicle is really 3 switches in one. One part of the switch is for the stoplights. The other two parts are for the cruise control and, if not operating correctly, the cruise control will not operate. Also be sure to check the vacuum supply to the cruise control unit. It is not uncommon for a vehicle of that age to have cracked vacuum hoses. A cracked vacuum hose will result in a loss of vacuum supply. Too little, or no vacuum supply equals no cruise control. There are a few checks you can make with a voltmeter, but to get down and dirty with the cruise control on your vehicle requires a computer scan tool too.