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Hello. Does anyone know what it can be? I hear sucking sound on the driver side under the hood. Can not understand where exactly it comes from. May be you guys can give me a hend with it? Here is the record of THE SOUND.
Post your vehicle specifics so we know which model. In the meantime check the vacuum elbow way in the back center of the intake. You have to pull it off to inspect it for cracking.
Do I need to take intake off to inspect the vacuum elbow?
Vehicle specs is 1999 Lincoln Navigator. You can see engine on the picture. 4r100 transmission.
I would buy a smoke machine and test the intake for leaks before anything else. Or take it to a shop that has a smoke machine and let them do it. I wouldn't just pull off the intake manifold without testing with smoke first. Machanics Smoke Tester
Are you getting any DTC codes or check engine light ?
Based on the other thread is this a dual-fuel system? Gasoline and Propane or CNG?
Welcome to FTE!
First post were more like inroduction. Yes, its dual-fuel system. I havent try cng yet but in the manual of the gas setup I read that both gases can be used. Same writen on the gas filters under the hood. But gas has nothing to do with that sound. I did the sound record when car were working on petrol. Also gas system ingages whet gas reductor worms up to the desired tempeture.
I would buy a smoke machine and test the intake for leaks before anything else. Or take it to a shop that has a smoke machine and let them do it. I wouldn't just pull off the intake manifold without testing with smoke first. Machanics Smoke Tester
Are you getting any DTC codes or check engine light ?
-Mike
Hello Mike. Yes, I have two codes. One is the celinder 5 misfire and 2nd is the System too lean, bank 2. No check engine light.
Hola Amigos. Today was a wonderful day. Good autumn weather with nice autumn sun. Since I didnt get any anwers I diceded to take intake off and take a look on the vacuum line behind it. To be honest it wasnt so hard job.I was in no hurry and did everything slowly.
Vacuum line turned out to be fine, at least I didn't find anything broken or cracked, but there were almost no gasket between EGR and Intake, so I think that is the place where air were sucked.
Tomorrow I want to measure cylinder pressure before changing spark plugs. Btw , take a look on the pic, I think EGR never has been changed. Im not gonna touch it as well, let it work until its dead.
10-04-2018, 11:06 AM
