1995 Jeep Grand Cherokee, knocks. tried to eliminate knocking but unsuccessful. Should I buy a new car?

Question

I drive a 1995 Jeep Grand Cherokee, and my engine has been knocking for the past few months. I've tried filling it up with the highest octane gas, but the knocking has recently returned. The knocking is not a ticking sound, but a higher pitched, pinging sound. The car has 199K miles on it, and is in fairly good condition.
Due to its age and its mileage, my Jeep is only worth about 2,000 dollars. Therefore, it isn't worth sending it to a dealer, having it repaired, and having to pay an expensive bill. I've tried changing the oil as well, but the engine still sporadically knocks, especially when the car is accelerating. Should I continue to drive the car regardless of the engine knocking, or is it time to buy a new car?

Answer 1

Or just buy a replacement engine for about $500.

Answer 2

Here is my .02

If you buy a new car you are looking at a $400+ dollar car payment, if you buy a new, average priced car, and pay that for the next 4 to 5 years.

OR....

Spend $1000 - $3000 and you can have a rebuilt engine installed usually with at least a 1 year warranty. Even if you have to take out a loan or use a payment plan you will be way below the total for a new car.

Then again if you are looking for a reason to get a new car, go ahead and get it, why look for an excuse?

Answer 3

If high test gas does not help at all, I would go back to regular gas and continue driving it until I get a new vehicle. At 199k miles, I would not worry too much about what sounds the engine makes, as long as it keeps running. And make sure the cooling system and thermostat are in good working order. Running too hot can cause knocking.

Answer 4

1995 Jeep

Answer 5

Arthur came up with a pretty reasonable solution to start with, a tuneup is always the best thing to start with before doing anything drastic. I'm at 190,000+ miles on my 96 and it has a knock to it when its cold but after it warms up it quiets down. Also if you decide to do your own tune-up, make sure the parts store gives you the right rotor. When I did my tune-up they gave me the rotor for the V8 engine instead of the I6, which worked for about a week and then disentigrated on my way to work one morning and left the vehicle dead along the side of the freeway.

Answer 6

i drive a '98 Jeep Grand Cherokee and mine has close to 300k miles on it. I also noticed a high pitched noise coming from my engine so i'd say it's a common issue for aged Jeeps. I suggest you drive it until it rolls to a stop and in the mean time start looking for a new car.

Answer 7

There is a service bulletin at your jeep dealer on this.
Spark knock, misfire, surge @ 45mph in 4th with 3.9, 5.2, 5.9L 1994-98 Grand Cherokee (18-48-98). The bullein number in ( ). I think they had to reflash the computer.
Good Luck
PS You DO NOT have a Knock Sensor.

Answer 8

If changing the oil changes the problem, look for a bearing situation instead of a gas situation. Try a fresh oil change and go up one SAE weight, like from a 30W to a 40W. If the engine quiets down, then its bearings and you need a new car before the engine blows.

Answer 9

did you check the spark plugs, the wires and the distributor? is the engine timing correct? what about the fuel pump?

it may be time to buy a new car or a new engine. if you took good care of the truck then a new engine would be cheaper. asses your situation. are you ready to be making payments again? are you ready to give up on a truck that has served you? are you ready to let go of a truck full of memories?

Answer 10

There is a knock sensor on the engine that sends a message to the brain to retard the ignition timing. Evidently that sensor is going bad. Call an independent shop, tell them what you have posted here and get an estimate.