vacuum leak...very frustrated
Thread Starter
Intermediate
Joined: Mar 2010
Posts: 32
Likes: 1
From: Hagerstown Maryland
vacuum leak...very frustrated
Hi everyone,
I was hoping someone could give me some advise regarding a vacuum leak. 6 months ago I repaired the vacuum line under the battery that goes to the rear of the intake manifold. I also repaired the connection from the vacuum tank/cylinder behind the battery that leads to the purple vacuum line behind the glove box.
I now have another vacuum leak that I cannot find. The a/c vents won't switch from dash to defrost, etc...They stay in the same position all the time. Also I thought I read where there is a vacuum line that goes to the air pump as well and during this time, the air pump stopped coming on and I got the P0410 code. I have already checked the lines that I repaired and all seems fine.
Does anyone know for certain if there is a vacuum line that goes to the air pump? I looked low and high and din't find anything.
Are there any more vacuum lines that I could check? I only see 2 lines coming from the vacuum canister under the battery (1 to the the glove box and 1 to the manifold)
Any help would be greatly appreciated.
I was hoping someone could give me some advise regarding a vacuum leak. 6 months ago I repaired the vacuum line under the battery that goes to the rear of the intake manifold. I also repaired the connection from the vacuum tank/cylinder behind the battery that leads to the purple vacuum line behind the glove box.
I now have another vacuum leak that I cannot find. The a/c vents won't switch from dash to defrost, etc...They stay in the same position all the time. Also I thought I read where there is a vacuum line that goes to the air pump as well and during this time, the air pump stopped coming on and I got the P0410 code. I have already checked the lines that I repaired and all seems fine.
Does anyone know for certain if there is a vacuum line that goes to the air pump? I looked low and high and din't find anything.
Are there any more vacuum lines that I could check? I only see 2 lines coming from the vacuum canister under the battery (1 to the the glove box and 1 to the manifold)
Any help would be greatly appreciated.
Tech Contributor
Joined: Jan 2007
Posts: 19,493
Likes: 1,178
From: Dyer, IN
Hi everyone,
I was hoping someone could give me some advise regarding a vacuum leak. 6 months ago I repaired the vacuum line under the battery that goes to the rear of the intake manifold. I also repaired the connection from the vacuum tank/cylinder behind the battery that leads to the purple vacuum line behind the glove box.
I now have another vacuum leak that I cannot find. The a/c vents won't switch from dash to defrost, etc...They stay in the same position all the time. Also I thought I read where there is a vacuum line that goes to the air pump as well and during this time, the air pump stopped coming on and I got the P0410 code. I have already checked the lines that I repaired and all seems fine.
Does anyone know for certain if there is a vacuum line that goes to the air pump? I looked low and high and din't find anything.
Are there any more vacuum lines that I could check? I only see 2 lines coming from the vacuum canister under the battery (1 to the the glove box and 1 to the manifold)
Any help would be greatly appreciated.
I was hoping someone could give me some advise regarding a vacuum leak. 6 months ago I repaired the vacuum line under the battery that goes to the rear of the intake manifold. I also repaired the connection from the vacuum tank/cylinder behind the battery that leads to the purple vacuum line behind the glove box.
I now have another vacuum leak that I cannot find. The a/c vents won't switch from dash to defrost, etc...They stay in the same position all the time. Also I thought I read where there is a vacuum line that goes to the air pump as well and during this time, the air pump stopped coming on and I got the P0410 code. I have already checked the lines that I repaired and all seems fine.
Does anyone know for certain if there is a vacuum line that goes to the air pump? I looked low and high and din't find anything.
Are there any more vacuum lines that I could check? I only see 2 lines coming from the vacuum canister under the battery (1 to the the glove box and 1 to the manifold)
Any help would be greatly appreciated.
Unless you replaced the entire vacuum line from the intake manifold to the vacuum tank, then you may in fact have another break somewhere. First thing I would do, is hook up a vacuum gauge to the line from the manifold(source vacuum)...this should be checked disconnected from the tank. See what the reading is. If thats good, then you know the issue is with the tank, fittings, or downstream. You can also use a hand vacuum pump w/gauge, and apply vacuum to the tank, and line to the A/C system.....to see if it holds vacuum.
Don't get frustrated, it's very easy to isolate.
Thread Starter
Intermediate
Joined: Mar 2010
Posts: 32
Likes: 1
From: Hagerstown Maryland
Thanks Lucky. I appreciate your help. I was driving myself crazy looking for the vacuum line to the air pump. I'll have to bite the bullet and take the manifold off again to check that line (I've tried, but I can't get my hand behind there without moving the manifold). Hopefully, that will be the last time I have to remove it for a while.
Thanks again.
Thanks again.
Racer
Joined: Apr 2005
Posts: 456
Likes: 15
From MadMatt's thread on same subject:
Work from the passenger side:
Take off the fuel rail cover, you can also remove the coil bracket off the valve cover, unplug the MAP sensor wire clip -
Now the 1/8" vacuum connection is just "UNDER" the MAP sensor - the best way to look at it is with an inspection mirror and a flashlight, once you have the wires to the MAP off it is easier to see -
If you removed the Coils (3 10mm bolts and the wire clip) you will have a substantial more amount of room to work with - lift any wires that need to be adjusted in order to see and work - I guess if you really wanted you could also remove the valve cover, do not worry about the gasket it is re-usable (O-Ring Style ) not like the old days when they would rip
I have big hands and forearm but small wrists, so this still was not easy but it is doable with the mentioned things removed - make sure you look under the MAP sensor with the wires unclipped and you will see it and then slide your hand/arm in there and feel for the hose and remove it and then put some Silicone Lube or SPIT on the new one and push it over the "NOW" exposed Vacuum nipple.
Hope this helps you, I'll be tyring this after I look through the fender.
Work from the passenger side:
Take off the fuel rail cover, you can also remove the coil bracket off the valve cover, unplug the MAP sensor wire clip -
Now the 1/8" vacuum connection is just "UNDER" the MAP sensor - the best way to look at it is with an inspection mirror and a flashlight, once you have the wires to the MAP off it is easier to see -
If you removed the Coils (3 10mm bolts and the wire clip) you will have a substantial more amount of room to work with - lift any wires that need to be adjusted in order to see and work - I guess if you really wanted you could also remove the valve cover, do not worry about the gasket it is re-usable (O-Ring Style ) not like the old days when they would rip
I have big hands and forearm but small wrists, so this still was not easy but it is doable with the mentioned things removed - make sure you look under the MAP sensor with the wires unclipped and you will see it and then slide your hand/arm in there and feel for the hose and remove it and then put some Silicone Lube or SPIT on the new one and push it over the "NOW" exposed Vacuum nipple.
Hope this helps you, I'll be tyring this after I look through the fender.
Thread Starter
Intermediate
Joined: Mar 2010
Posts: 32
Likes: 1
From: Hagerstown Maryland
Thanks wwwFLA,
I will try removing the coil pack and see if I can get my hand in there. That would save a lot of time not having to remove the manifold. If I remember correctly the air tube from the air pump system may also be in the way, but I will give it a shot.
Thanks for the help.
Best regards,
Tim
I will try removing the coil pack and see if I can get my hand in there. That would save a lot of time not having to remove the manifold. If I remember correctly the air tube from the air pump system may also be in the way, but I will give it a shot.
Thanks for the help.
Best regards,
Tim
Tech Contributor
Joined: Jan 2007
Posts: 19,493
Likes: 1,178
From: Dyer, IN
Thanks wwwFLA,
I will try removing the coil pack and see if I can get my hand in there. That would save a lot of time not having to remove the manifold. If I remember correctly the air tube from the air pump system may also be in the way, but I will give it a shot.
Thanks for the help.
Best regards,
Tim
I will try removing the coil pack and see if I can get my hand in there. That would save a lot of time not having to remove the manifold. If I remember correctly the air tube from the air pump system may also be in the way, but I will give it a shot.
Thanks for the help.
Best regards,
Tim
Burning Brakes
Joined: Apr 2008
Posts: 855
Likes: 40
From: Liverpool NY
There is a vacum canister and check valve inside the fender well that ties everything together. You will need to pull the passenger tire and open the access panel to get this. When I had my leak I had to replace most if not all the lines and check valve.
Tech Contributor
Joined: Jan 2007
Posts: 19,493
Likes: 1,178
From: Dyer, IN
".....I also repaired the connection from the vacuum tank/cylinder behind the battery that leads to the purple vacuum line behind the glove box"
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Thread Starter
Intermediate
Joined: Mar 2010
Posts: 32
Likes: 1
From: Hagerstown Maryland
Yes, I already have the battery out and inspected the vacuum canister area and everything looks fine. I intalled a new check valve, new line to the cabin and spliced a new line to the manifold under the battery tray about 6 months ago. I am hoping that there is just a break in the hose going to the manifold inside of the wire harness that runs behind the engine (I didn't replace that section of hose originally)
I will need to get a vacuum tester on my way home today and check each connection on the canister, as well as the canister.
Unfortunately, I didn't have time last night ot work on it, so hopefully, I will get it taken care of tonight.
I appreciate the input from everyone who responded. I'll let you know how I make out.
I will need to get a vacuum tester on my way home today and check each connection on the canister, as well as the canister.
Unfortunately, I didn't have time last night ot work on it, so hopefully, I will get it taken care of tonight.
I appreciate the input from everyone who responded. I'll let you know how I make out.
Thread Starter
Intermediate
Joined: Mar 2010
Posts: 32
Likes: 1
From: Hagerstown Maryland
O.k. I just got home and tested the vacuum in the line going to the intake manifold. It is holding pressure (needle moving very slowly down) which I assume would mean it is good since the intake isn't air tight until the engine is running.
I tested the line that goes into the cabin and the needle dropped immediately. I disconnected the line at the purple vacuum line connector and it is holding between the tank and that point. I then connected the vacuum tester directly to the purple line that goes under the dash and the needle dropped immediately. Should this line keep a vacuum? I assume it is going to the manual vent switch in the dash, but I wasn't sure if this line should hold a vacuum or not. I'm sorry for the ignorant questions, but I have almost no experience with vacuum systems in cars.
Once again, any input would be appreciated.
I tested the line that goes into the cabin and the needle dropped immediately. I disconnected the line at the purple vacuum line connector and it is holding between the tank and that point. I then connected the vacuum tester directly to the purple line that goes under the dash and the needle dropped immediately. Should this line keep a vacuum? I assume it is going to the manual vent switch in the dash, but I wasn't sure if this line should hold a vacuum or not. I'm sorry for the ignorant questions, but I have almost no experience with vacuum systems in cars.
Once again, any input would be appreciated.
4th Gear
Joined: Aug 2010
Posts: 4
Likes: 0
Check out some videos on YouTube that will give you a better idea http://www.youtube.com/watch?v=YH6306zM-Ug
Tech Contributor
Joined: Jan 2007
Posts: 19,493
Likes: 1,178
From: Dyer, IN
O.k. I just got home and tested the vacuum in the line going to the intake manifold. It is holding pressure (needle moving very slowly down) which I assume would mean it is good since the intake isn't air tight until the engine is running.
I tested the line that goes into the cabin and the needle dropped immediately. I disconnected the line at the purple vacuum line connector and it is holding between the tank and that point. I then connected the vacuum tester directly to the purple line that goes under the dash and the needle dropped immediately. Should this line keep a vacuum? I assume it is going to the manual vent switch in the dash, but I wasn't sure if this line should hold a vacuum or not. I'm sorry for the ignorant questions, but I have almost no experience with vacuum systems in cars.
Once again, any input would be appreciated.
I tested the line that goes into the cabin and the needle dropped immediately. I disconnected the line at the purple vacuum line connector and it is holding between the tank and that point. I then connected the vacuum tester directly to the purple line that goes under the dash and the needle dropped immediately. Should this line keep a vacuum? I assume it is going to the manual vent switch in the dash, but I wasn't sure if this line should hold a vacuum or not. I'm sorry for the ignorant questions, but I have almost no experience with vacuum systems in cars.
Once again, any input would be appreciated.
Thread Starter
Intermediate
Joined: Mar 2010
Posts: 32
Likes: 1
From: Hagerstown Maryland
I bought one of those hand operated vacuum pumps and used it to draw a vacuum on the lines. I drew a vacuum on the line going to the manifold with the hand pump and it very slowly drew down, which I assume is from the opening at the throttle body. I haven't tried to see if the manifold will draw a vacuum yet, because I have the battery out of the car. I thought I would try this method first.
The one that has me puzzled is the purple line that goes under the dash. I don't know if that line is supposed to be vacuum tight at all times or only when it is being switched (i.e. it only needs vacuum when you change the settings for the heat or a/c vents)
The one that has me puzzled is the purple line that goes under the dash. I don't know if that line is supposed to be vacuum tight at all times or only when it is being switched (i.e. it only needs vacuum when you change the settings for the heat or a/c vents)
Thread Starter
Intermediate
Joined: Mar 2010
Posts: 32
Likes: 1
From: Hagerstown Maryland
I finally found the bad hose! It was the one going to the back of the intake, just as Lucky suggested. I did as Lucky said and hooked up the line and started the car and there was no vacuum. Apparently there was another break in the hose directly behind the engine inside the wiring harness, where I could not see it.I ran a new vacuum line and hooked it back up the gauge and it was pulling a strong vacuum. The vents are switching as they should be. I would like to thank everyone who chimed in on the post and especially Lucky.
You all are the reason this forum is so succesful.
Thanks again.
Tim
You all are the reason this forum is so succesful.
Thanks again.
Tim
Tech Contributor
Joined: Jan 2007
Posts: 19,493
Likes: 1,178
From: Dyer, IN
I finally found the bad hose! It was the one going to the back of the intake, just as Lucky suggested. I did as Lucky said and hooked up the line and started the car and there was no vacuum. Apparently there was another break in the hose directly behind the engine inside the wiring harness, where I could not see it.I ran a new vacuum line and hooked it back up the gauge and it was pulling a strong vacuum. The vents are switching as they should be. I would like to thank everyone who chimed in on the post and especially Lucky.
You all are the reason this forum is so succesful.
Thanks again.
Tim
You all are the reason this forum is so succesful.
Thanks again.
Tim
