Chrisjwc19

So I noticed after I changed my spark plugs, tips, and oil change. My engine went from having a lifter tick noise to having a rod knock noise. Now, I'm not 100% if those were the exact noises but it's what I'm being told. Also, not e the idle is less than 1000 rims and fluctuating slightly. Bought this in a rush (Yeah I know I'm dumbass) but needed something quick. It's been nothing but problems. After driving awhile the noise does go down a little. Also, notice that I go thru gas worse then my dad's 1500 truck. I put platinum Bosch spark plugs, Napa TPS, and rotella 15w40. All which was recommended from Napa. It's a 1999 XJ 4.0 AW4 automatic with a Command Trac transfers. What did I do wrong?

bryanintowson

Previous owner may have been running heavy weight oil to hide the rod knock.

DeltaOP4

Check distributor cap and rotor for moisture and corrosion. Super easy and cheap. Idle air control may be dirty/bad. Try cleaning that and see if it helps. If not you may need to replace it, which again is really easy. And lastly as far as bad fuel economy your throttle positioning sensor may be bad. Also really easy.

Chrisjwc19

I planned on changing cap, rotor, and wires this weekend. When doing so I'll check out the IAC. I did replace the TPS with what Napa said was OEM. Also had to adjust my TV Cable which was very loose. Just found out I have to replace my whole front suspension pretty much, and hub assembly. Should I wait to replace all that till I'm ready for a lift?

DeltaOP4

Depends on what you want to replace and when you can do it. Is it a daily driver?

Chrisjwc19

Yes it's a daily.

XJlimitedx99

If I were you I would run it as it is for awhile and figure out what's going on in the motor. Next oil change put 10w-30 in it (that's what it's supposed to take) and see what the noise is like. Sometimes people will run heavier weight oil to hide bad engine noises. Unless you just want to say screw it to the motor and run it till it dies then replace it. What's it have for miles?

Chrisjwc19

It has 225,000 miles

XJlimitedx99

that's not too bad for these motors, but if it hasn't been taken care of then it could start developing problems.

With that being said, I know people that have driven with some pretty bad noises for like 50k miles on these motors and they just keep on going.

DeltaOP4

Then I would take care of the boring stuff that won't be replaced when you out the lift in first. A lift is going to change angles in the front end and out some extra stress on stuff. Change the hub, and all the worn stuff that you don't plan on replacing during the lift install.

Chrisjwc19

Okay will do this weekend. Give update after. Thank y'all!

Waynerd

When my water pump was bad it sounded like rod knock.