knock sensor with intake gaskets?

aff16falcon · June 11, 2019

Hey guys. Got a 2002 1500 4x4 with the 4.8 and 187k miles. Started throwing a white exhaust cloud, but it’s very thin. Low coolant light came on so definitely got a leak it would seem. Ran a dye test and no exhaust detected in the coolant reservoir. So I’m going to try replacing the intake manifold gaskets. My question is...does it make sense to do the knock sensors too since i’ll be right there anyway? They are the original knocks, but they still work and there aren’t any signs of a bad sensor. Ain’t broke don’t fix it?

txab · June 11, 2019

iirc, that's not a wet intake

I'd look into this:

http://ww2.justanswer.com/uploads/Bluegorilla/2008-12-05_142924_Coolant_loss_5.3.pdf

But, to answer your question, I'd replace the knock sensors at this time, if they've not been replaced before. Replace the wiring harness too

Edited June 11, 2019 by txab

DeePa · June 11, 2019

Dry intake. If it isn’t broken, don’t fix it.

Could be losing coolant from many places. I’d find from where and go from there.

Is the coolant reservoir low? Did you check the WP weep hole?

Could be the castech failure but I’d think that would have happened well before 180k. I had that failure on my 04. If I remember, it was blue smoke at startup for me.

Check the oil fill to look for butter scotch and see if your oil is sludge like when you first drain it.

riverbanks · June 11, 2019

I pull plugs,look for the odd colored one,clean, maybe that can isolate to what bank is the problem

SILVER SLED · June 11, 2019

Coolant doesn't flow through that intake.

dtnel78 · June 12, 2019

Thought of pressure testing the coolant system? Just a thought.....

aff16falcon · June 13, 2019

All great suggestions. Anyone know if it is possible to determine if I’ve got the Castech heads by VIN? Seems a lot easier than trying to find the stamp. Thanks for that link and to everyone for saving me from doing the intake job. Didn’t know it was a dry intake. I’ll check the weep hole this weekend.

This is a very small leak. I added coolant about a month ago and there is still no noticeable decrease in fluid since then. I’m pretty confident it’s not just the sensor that gave me the low coolant warning since I have thin white smoke in the exhaust. Spark plugs all appear normal and so did the oil. I’m running out of ideas and may just pay the dealer the diagnostic fee to find where the leak is at. On a side note, this is my farm truck. I’d like it to last me several more years, but if it’s going to require new heads, it ain’t worth the money.