any gurus here please help. i cant figure out where is the vacuum leak on my cat! X type 20L. i almost replaced everything.

new booster
new vacuum hose
new sparkplugs
new ignition coil
replaced throttle
replaced icv
replaced tps
resealed imt rings
resealed intake manifold gaskets
borrowed airmass sensor
checked almost every hose for air leak, seems all is good.

 

jaghelp.com: Jaguar X-type common vacuum leaks. P0171 and P0174

https://www.jaguarforums.com/forum/x...2004-a-172133/

 

Btw, you ARE talking about a vacuum leak and not an EVAP leak, correct?

 

"resealed intake manifold gaskets"- Just what does that mean? Does that mean you replaced them with new ones or did something else? If you did something else, I would suggest changing them with new ones.

"borrowed airmass sensor"-Same thing. Not sure what you mean by this? You mean you changed yours out from one from a different car?

Do you have a specific code(s) you are getting? If so, post them. Also, when you changed any of the parts did you clear the codes and then see what, if anything came back? If not, do that so you know what it new and you aren't chasing an old stored code.

 

eurocare, I say invest in a good cigar. If you don't smoke, I am sure a friend of yours will "take one for the team" and smoke it for you. With the engine cold and the A/C off, start up the car after they have the cigar going good. Have them gently blow the smoke into the engine bay and watch the smoke move. Where you see the smoke make a sudden change in direction towards the engine, that is where your vacuum leak is. From there it is a matter of determining the seal that is there and replacing it. Do not just be looking at the joints where parts come together, but be looking at the entire length of tubing and also where the tubing joins the engine.