Cold Idle Tapping > At least check this >
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From: SW Florida
Cold Idle Tapping > At least check this > I have posted this many times before. Piston slap is a very good posibility, but, before you convince yourself that you indeed have piston slap, try this first:
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Start your cold engine in the morning. After about 1 minute, does it start “tapping”? Tapping lasts until the engine warms up and then stops? You may just be a victim of the “Purge Valve From Hell”. Your fuel vapor purge valve is located right next to the #1 fuel injector. That’s the most forward injector on the driver’s side. One of the hoses that are wrapped in silver tape mounts to this valve.
Now that you have identified the purge valve, start your [cold] engine and let it idle. As soon as the tapping sound starts, unhook the electrical connector to the valve (while engine is still idling).
If the tapping sound stops, you have found the problem. Your warranty will replace the valve, but it’s just a crapshoot whether you get a quiet one or not. If you are not under warranty, I believe the valve costs under $50.
Just another posibility
Good Luck,
Ron
_________________________________________________
Start your cold engine in the morning. After about 1 minute, does it start “tapping”? Tapping lasts until the engine warms up and then stops? You may just be a victim of the “Purge Valve From Hell”. Your fuel vapor purge valve is located right next to the #1 fuel injector. That’s the most forward injector on the driver’s side. One of the hoses that are wrapped in silver tape mounts to this valve.
Now that you have identified the purge valve, start your [cold] engine and let it idle. As soon as the tapping sound starts, unhook the electrical connector to the valve (while engine is still idling).
If the tapping sound stops, you have found the problem. Your warranty will replace the valve, but it’s just a crapshoot whether you get a quiet one or not. If you are not under warranty, I believe the valve costs under $50.
Just another posibility
Good Luck,
Ron
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From: Nawf Carolina
Re: Cold Idle Tapping > At least check this > That is the exact discription of what is happening to my engine <img src="gr_stretch.gif" border="0"> I'm gonna have to test it now. Thanks Ron <img src="gr_grin.gif" border="0">
J.
J.
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From: MD
Re: Cold Idle Tapping > At least check this > My car does this and I went out with the stethoscope and listened to all the injectors. The tapping in my ear seemed to be the same as what I was hearing. Right on beat. Why are they soooo loud, some of course more than others.
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From: SW Florida
Re: Cold Idle Tapping > At least check this > J.
Certainly hope you just have a noisy purge valve.
I can tell you, I now have a new one, but its just as noisy as the old one. Like I said; "Its a crapshoot".
BTW, the reason the purge valve will not make tapping noises immediatly after cold engine start is becouse this valve is commanded by the PCM to operate a minute or so [after] cold engine start. Then the valve stops operating after the engine/PCM sees a certain temp. Noise stops.......
The real key is; If your tapping sound increases in speed as the engine increases in its revs, its not the fuel vapor purge valve. A noisy fuel vapor purge valve will tap at a pretty much constant value even if the engine is rev'd slightly above idle (but may be harder to identify if the engine is rev'd......
Anyway, pulling the electical connector on it just take a few seconds of your time.
Certainly hope you just have a noisy purge valve.
I can tell you, I now have a new one, but its just as noisy as the old one. Like I said; "Its a crapshoot".
BTW, the reason the purge valve will not make tapping noises immediatly after cold engine start is becouse this valve is commanded by the PCM to operate a minute or so [after] cold engine start. Then the valve stops operating after the engine/PCM sees a certain temp. Noise stops.......
The real key is; If your tapping sound increases in speed as the engine increases in its revs, its not the fuel vapor purge valve. A noisy fuel vapor purge valve will tap at a pretty much constant value even if the engine is rev'd slightly above idle (but may be harder to identify if the engine is rev'd......
Anyway, pulling the electical connector on it just take a few seconds of your time.
Thread Starter
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Joined: Nov 2001
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From: SW Florida
Re: Cold Idle Tapping > At least check this > Beth, as with any fuel injector, they are all fairly noisy.
A noisy purge valve sounds more like just 1 or maybe 2 lifters making noise.
Tap Tap Tap Tap <img src="gr_emb.gif" border="0">
A noisy purge valve sounds more like just 1 or maybe 2 lifters making noise.
Tap Tap Tap Tap <img src="gr_emb.gif" border="0">
