[ygdude]

looking at a 2004 concorde lxi

the motor has a bit of a knock/rattle in it.

Sounds low in the engine but i can only hear it clearly on the drivers side and it almost sounds like it is coming from the rear of the engine but is a bit hard to tell. It is also a bit intermittent and seemed to fluctuate a bit with the AC on and when shifted from R to N to D and back and forth.

didn't really make any noise when first started "cold" kinda cool here today.

Anyone run into this before? likely rod knock or flywheel/torque converter noise or something else???


Thanks.

 

[ImperialCrown]

Proceed with caution. Although maybe not a deal-killer, if it does need a flexplate you would want a price drop accordingly.
Diagnose this first before continuing. If the rest of the car is clean and this appears to be the only major problem (and not an internal engine knock), it could make a nice car. Or you could walk away from it.

 

[ygdude]

Flexplate?

 

[ImperialCrown]

Flexplate = Flywheel. You may see shiny spots on the torque converter bolt heads if they are hitting on the block. A cracked flywheel can also be noisy. Locate the noise source from underneath the best you can.

 

[ygdude]

I thought that you probably meant flywheel.

In my quest to replace the 2003 Intrepid ES that was totaled (thinking now I should have bought back) i've come across several 3.5's that have "rod knock". Have only heard one and it was toast, rattle on top and knocking bad on bottom, I think the kid that had it run out of oil. looked at it as a possible car to put a new motor in but he had trashed the whole thing. This Concorde was advertised with motor problems. Was surprised when 1st started it didn't make any noise at all. then the slight wrapping noise on the drivers side near the rear of the engine.

If a flywheel is there any way to check under load (sitting still and carefully power braking)? would the load make is worse??

To your 1st post. The car is very clean with only a couple battle scars/parking lot dings but not many really. newish goodyears all around 122000 miles. their asking 1900 but I'd try to go lower. Even with a new (used) motor at $500 (local rate) that's not a bad price other than alot of labor (mine) to fix it.

It does idle a bit rough and lopes a bit idling.

Thanks again for the help

 

[FIREM]

Have seen a few 3.5 with rod bearing issues. Flexplate/flywheel also suspect. Usually Flexplate/Flywheel issue will "rattle" more as you shut the engine off. As the engine comes to rest the torque converter wants to keep going. Try to start and stop the engine neat a wall so you can hear the sound reflect back to the car.
If it is a rod bearing issue usually gets louder at decelleration. Race the engine a little and listen carefully as you quickly let it go back to idle.
These engines also tend to have a little rocker ticking at start up and at times when idleing.
Good luck checking it out.

 

[ygdude]

Thanks for the feedback.

Might go take another look Sat if I can get over there.

Car is really nice shape but not sure I want to tackle a motor right now. Even though it would still be a good deal.