99 Expy with 5.4. I noticed oil laying in the valley under intake. Is this a common issue, and where is it coming from? Also, seems to produce an awful lot of water/condensation dripping underneath. Is this common? Thanks

Tommy

 

I had a similar problem but it was coolant from the heater return pipe to the water pump leaking. If the coolant mixes with grease/grime it may look like oil. I had to pull the intake manifold and replace the two o-rings where the pipe meets the water pump.

 

Thanks...I believe you are right..

 

I have another thread going asking for help diagnosing my inconsistent coolant leak. When I first saw the puddle, I didn't think it was coolant because it looked more like oil. But it's consistency and smell, and then a mechanic told me it was coolant.

Where did you see this leak?

 

If you think it is coming from the back of the motor, the heater hose that runs under the intake manifold could be the culprit. If you look under the alternator, you will see the valley under the intake. The pipe that runs front to back would be the heater hose. This is on a 5.4.

Tommy