Hey all,
I finished up the Plenum repair project, replaced my IAC, replaced my EGR valve and solenoid, replaced the thermostat, replaced my oil pressure switch/sending unit.

When I drive the truck now it seems to have little power and when I am on the throttle at all it has a very loud air sound that I can hear. When I take my foot off the throttle it goes away. As I coast/slow down to a slow speed it ALMOST dies out. It has no issues starting or idling and I did notice when maintaining speed around 35-45 it seems about every 3 seconds it 'misses a beat'. When I pulled it into the garage it smelt like hot plastic/rubber (not sure if this is related to a bad pulley and it stressing my belt but, this wasn't an issue prior to the Plenum Repair) My coolant level fluctuates from middle (cold start) to full (after idling/warming up) and after driving for about 10 minutes I checked and it was sitting in the middle still. It just doesn't seem to have the normal response when I accelerate.

Now, my concerns are bad CAT or a bad Plug/plug wire or both but wasn't sure what this 'Air' sound would be coming from?

Any thoughts/suggestions would be greatly appreciated!

Thanks for your time!

 

Have the cat tested before you crack a head. And the noise could be from the TB, did you install the round gasket that goes between the air hat and TB?

 

[YOUTUBE]http://www.youtube.com/watch?v=e9TWS28XyQo&feature=youtu.be[/YOUTUBE]

Here is a video I installed a new gasket between air hat and TB...still same loud air sound....at low speeds of gas it seems like it wants to die. BUT it doesn't. It seems to work harder to get up to 45 mph or above than it should. Thoughts? This truck is starting to upset me now. hahaha.

 

Can you put a vacuum gauge on intake and see what it is pulling? Sounds like it may be a crankcase leak. Most likely source (assuming all vacuum lines were installed correctly) will be the rear seal between intake and block. Not really vacuum as it is isolated from intake. That rear seal can be tricky as old seal sometimes delaminates upon removal, leaving part of it in place and keeping new seal from sealing correctly.

 

So if I hook up this vacuum gauge/test what should I be looking for? If it is the rear seal on the intake and block this means all the same work as a Plenum repair? except the plate and gasket of course...Thanks for your help!

 

Vacuum at idle should be around 20.

Rear seal would involve pulling intake back out. Do you still have the pieces around that you took off when you pulled intake? If so, take a look at the old seal. Post up a photo if you can. There should be a few rubber pieces about the size of a toothpick protruding down that go into the block. It is pretty easy when putting intake in to push this seal out of place.