2002 3.8 liter

[Wendy1234]

My 2002 3.8 with only 56k has a rod knock! is this common in the 3.8 in the past i've only had the 3.3, i love my van but i can't keep it with a knock. is this common? i only want a caravan but i won't trust the 3.8 after this. help

[Bernard Feltzer]

Are you the original owner of the vehicle?
What was your maintance schedule?
Did you ever change the oil?

It is uncommon for that engine to have a rod knock unless you were drag racing it.

[Wendy1234]

I am not the orginal owner so I don't know if it was maintained. a friend has a 2000 with a 3.8 and he also heard a knock during the winter in his. I thought these van's were known for tranny issues not motors. Thanks

[RIP]

Exactly when do you hear the knock? As soon as you start when cold, after warm up, or under load?

[Wendy1234]

It only happens at start up, and not has often now that the weather is warmer.

[RIP]

Since it's not there all the time I would suspect oil isn't getting where it has to fast enough. As it warms, the oil thins slightly, finally getting to the valve train, getting rid of the noise.

Some cheap and easy steps:
> Make sure you are using the correct viscocity oil for your prevailing temperatures. Make sure it's topped off.
> Drain a little oil and smell it. If it smells like gas, the gas has thinned the oil and created your knock. Unfortunately, that would mean worn rings and cylinder damage.
> Pour a can of engine flush (Rislone, Gunk,etc) in the oil then change the oil and filter. This will clean any lite crud out of the valve train.
> You could try using an external oil pan heater during the winter to keep the oil thin so it will flow easier at startup.

Some more involved steps:
> Attach a direct pressure gauge at the sender to verify the pump is producing the correct pressure.
> Have a shop perform a professional flush of the oil system
> Last resort - take it to a trusted shop

One other possible source of your noise is the evaporative purge solenoid. It's under the hood on the passenger side. Two to three minutes after the engine starts it will activate and start making a noticable continuos click. When I first heard it I thought I had a knock. Wasn't the case.

Some of this may sound dier. More than likely this is a cold weather issue that can be easily fixed.

Is this common? Based on what I've read on this and other forums and what I've experienced with 3 3.8 ltr engines, no this is not common. These engines are fairly bullet proof. My 96 GC has 190+K miles on it and never skips a beat. On the other hand, my 87 Camry with 250+K miles will knock at startup sometimes when its cold or it has set a long time. I just let it idle a few minutes and it goes away. Other than that, it runs great.