Engine noise
 

I can't figure out what is causing my car to have trouble to hold idle when cold. When I start the car it pops and I am guessing it is early or late detonation. If I give it gas it doesn't do it. Once it's warm idle seems good and it no longer does this. Startup after that is fine until I let it cool back down.



Things that I have done recently are the oil, spark plugs, aos, sai, cleaned the intakes from the bad aos. I believe I was using 5w40 and now I have 5w50.

Before this the car sat for awhile only starting it up once a month to move it in and out of the garage. It did not start this until after I replaced aos, oil, and spark plugs. It ran great before sitting due to a wheel bearing that is also now taken care of.


Here is the sound. I cringe just listening to it.
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Check for vacuum leaks.

It appears I have a broken vacuum line. The one going from G to E in the attached picture. I can't see the E connection unfortunately. I may have to take thebpassenger side intake off to repair it.

What diameter are the vacuum lines? I purchased 5/32 because that is all I could find. https://uploads.tapatalk-cdn.com/202...1d3991b2f3.jpg

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Actually I just did all of this work,..your going to have to pull your Alt. anyway, its quicker than pulling the intake,..and if you can finesse your hand back in there you can connect the new vacuum line you wont have to pull your intake,.but I also did a fuel injector test,and replaced the vacuum canister( due to CEL throwing codes) plus I wanted to learn what it takes to get into these engines and I learned.!! It's fun if you have patience. Frank

I took the intake apart today and replaced a hose. I'm going to have to go back in though. I'm still having the problem. I think I might have damaged the hose between the electronic switch over and vacuum switch over.

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I also broke my oil fill tube on the engine side..that was stressfull dropped a piece of plastic down the hole after I chipped the tube taking it out,..

Does anyone know if E and D in the photo come on every time the car is started or if it's only when it's under such a temperature either engine or outside temp? How long does it stay on and does E just allow vacuum to pass through which activates D?

My reservoir would not hold a vacuum. I will try to repair the one I have with plastic weld or flex seal if I can locate the leak.

I did smoke test all weekend. It was incredibly difficult to find the problem. Every time I pumped smoke through it I was getting a cloud coming from both sides. It ended up having smoke coming from the spark plug tubes.

Replaced all 6 of them yesterday. Used the 4.5 inch screw with 2 nuts and 2 washers to get them out. Pushed back in with my hands. Torqued everything down. Just started it up and it went straight to warm up mode then idle without a single pop. Burned off all the excess oil that, I assume, the difference in pressure was creating while testing it. Now I have my Boxster back. Never saw a single engine code while trying to find my problem.