North American Turbocoupe Organization

Full Version: Tapping noise
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Well, I had posted about this before, but had no time to tear down to where the noise was.

Problem: was getting a very loud tapping noise from under the valve cover at 2.5k - 4.5-5k rpm when there was no load on the engine (ie. holding steady at that rpm on a straightaway or in neutral), but at WOT no noise, and when the gas is released, no noise.
Also - was having a small vac leak somewhere (was getting 16-17.5 at idle with a ranger roller cam), and was having veryvery delayed boost (15psi @ 4k rpm+).

I get to go back and play in the sand in Iraq for another year, but I have the next week to myself, so I went ahead and took off the valve cover, and I can't seem to find anything out of order so far.
All the rollers/sliders are all on track with no cracks or visible damage. I can't seem to see anything out of place, and I really dont want to take the cam out if I don't have to (nightmares from my first attempt to put it back in). But if thats the next step, then I just need to know some possible things to be looking for, maybe valves?

Thanks in advance -
Kramer
This may not help you out with the dealyed boost, but the "ticking" that you heard was probably the FPR. The stock ones seem to tick pretty loud. Try the old approach. Use a really long screwdriver or 1/2" drive extention like a stethescope. Start with the FPR then go to the valve cover and listen thorugh the tool. This will tell you a little better where the noise is comming from. Then when you find where it is comming from, then you can fix/diagnos the problem better.

Jim B Big Grin .
I had tried the whole auto stethoscope approach, and had narrowed it down to either inside the valve cover, or a fuel injector (somewhere in the general area), but had no idea. I'm at a dead end right now, everything under the valve cover seems to be the way it should. I'm stumped.
Some 2.3T injectors can tick pretty loud. Have someone rev it to the RPM is ticks, and pull each injector electrical connector one at a time and see if you can get the tick to stop.

Be safe in Iraq, and thank you for the job you are doing over there.