Can't find intake manifold leak.

[hazardsys]

I believe my 2001 ex sport has a leak in the intake manifold gasket, but I haven't been able to find it. I went all around it with carb cleaner trying to change in revs with no luck. Heres the symptoms, the usual 0171 and 0174 codes and when i rev it at the throttle body i can hear a sucking noise. It sounds similar to a secondary on a 4bbl carb kicking in and suckig in air. This is with air intake and all that attached. I also noticed the elbow attached to the valve right behind the throttle body on passenger side keeps collapsing at idle. When i rev it opens up some. Is there any one place that the gasket is prone to fail? Might help me to find the leak if I have a better idea where to look. Thanks.

 

[swshawaii]

If the PCV elbow is collapsing it's probably due for replacement. (See post #52)
http://www.explorerforum.com/forums/showthread.php?t=314670

If no cure there, you are overdue for upper and lower intake gaskets. GL
http://www.explorerforum.com/forums/showthread.php?p=487634#post487634
http://www.explorerforum.com/forums/showthread.php?p=2334474

 

[hazardsys]

Thanks. I'll check the PCV elbow later today. If it is the intake gaskets how long could i go with it leaking? I'd like to avoid putting too much money into this engine. The previous owner didnt take care of it very well and I know its probably a matter of time before major stuff like chain guides etc start going out. My plan is to do a 5.0 swap eventually.

 

[Flash]

I'm not sure why you need to find out where the gasket is leaking, if it's leaking it will need replacing everywhere.

 

[Erik727]

What Flash said.....I understand not wanting to put alot of cash into it...but you can get a set of lower and upper manifold gaskets as a kit for under $20..

97-01 4.0 SOHC Fel-pro # MS90890 $16.99 upper and lower

 

[bwheeler73]

Battery acid on purge valve under battery tray seen it a few times