Yeah, I''ve been crawling all over ebay, but I can''t seem to findthe right one. I see people who are posting what they say is the right part for my car, but the photo they are showing looks like a GM product from the 80s.


Also, have you ever heard of one of these things failing like this? I''m tempted to pry it open just for the hell of it, and see what exactly failed.

 

No....can''t say that I have.

How bad is the leak? I.E. Does the system still work correctly, with just an annoying noise, or when it''s making the noise some part of the system fails to operate?

 

The leak seems to have become progressively worse over time. When it first started, it would happen only once or twice a week. But during the middle of last week, it was continious. Also, I noticed that lately I was getting a rough feeling in the break pedal at idol. (I assume that this was due to a vaccuum leak). Also, the car became somewhat difficult to start, and would die when cold.


However, this past Saturday I went to the wrecking yard, and found a Crown Vic that had the same unit. Costs me $28.00. Far better than the $750 the dealer wanted.


I actually disassembled my failing unit, and removed the air valve from the unit. I plugged this into my car, by itself, and was able to determine that it is in fact the air valve inside the climate control head that was failing.


I took the air valve out of the unit from wrecking yard, and put it into my climate control head, and since then the sound has gone away, and so has the hard start and rough idle.


Looks like problem is solved for the meantime, but parts from the wrecking yard always seem to have a very limited life.


Well at least I know how to fix it, if it happens again.

 

Nice work!

Good job scoring the cheap parts. I''ve been spinning wrenches for 19 years and I''ve never had to replace a climate control head, which means nothing in this case....except I''ll bet your fix lasts.

 

One funny thing however, the whistling sound is completely gone, but I had another episode of the hard starting this afternoon when I left work. This is the first time its done it since the repair.


I openned the hood while I started it, and heard a strange moaning sound, like an air vibration coming from air filter housing, then when I hit the throttle it went away. Since there aren''t any butterfly valves in this area, I assuming that the problem must be something in the throttle body?


Any ideas?

 

I would give all the vaccuum lines thst are visible in the engine bay a real good once over so you can eliminate them as culprits. Also, do you have an open bottom EGR valve so that you can check if it is stuck open/closed? Good luck and good work!

 

Yeah I took a look at the Egr, it seems to working ok. I also put a small diameter hose in my ear, and ran it along each of the vaccuum lines, and I cannot find anything.


I''m starting to wonder if some manifold vaccuum is sent directly to actuator that controls the diverter valve located under the dash on the passenger side. It seems as though I hear a thunk sound, and then the engine sooths out.


BTW, started the car this morning, and no problems.

 

Ok, if anyone is still looking at this thread, I have some interesting news.


The part I got from the wrecking yard developed the same issue this past weekend. It now makes a high pitched whistling sound just like the old unit did.


However, I have noticed that the sound seems to only happen after I have been accelerating, for some distance, and then have to take my foot off the gas, as when traffic suddenly backs up. I can sometimes make the noise stop by hitting the off botton on climate control, or hitting the break real hard. So now there is no doubt that this is vacuum related.


Now I''m wondering if the climate control head is getting a faulty vacuum signal, which is causing the valve inside unit to fail? Maybe a vacuum signal that is too high when I take my foot off the gas pedal.


Does anyone know if there is some sort of check valve in the vacuum line between intake manifold and the climate control head that is supposed to reduct vacuum under certain conditions? Or does anyone know where I can find a detailed vacuum diagram for 98-02 MGM? (I''ve read that these years are the same).


Also, I removed the unit entirely, for the time being, and have plugged the lines with small machine screws, and the strarting problem I had earlier seems to have gone away.


(The good news is that I learned how to take apart my dash, and clean the dirty plastic cover on the speedometer.)


Any advice will be appreciated.

 

The primary vacuum schematic is on a sticker under the hood. I''ve got an 00-02 service manual that I''m looking through now for something more detailed.....but I''m not having much luck. I''ll post it if I find something.

 

Well it appears that the vacuum source starts at the throttle body, and then goes to a vacuum block mounted on firewall, then from there it goes through the firewall, into passenger compartment.


I''m assuming that there must be some type of storagevacuum canister inside the dash, with perhaps a second check valve climate head and canister.


I plan on connecting a vacuum gun to the line leading from throttle body, and connecting a vaccum guage to the line supplying climte control head to see if I can detect any leakage, or anything else.


I also plan on going back to the wrecking yard tomorrow, and completely take apart the dash of a similar crown vic, to see where this line is going inside dash.


Any othe ideas?