DPHC13

I hate to say this with every post but I am totally new to Stangs. I have a 2008 GT 5-speed and on cold mornings it has a knocking noise when I'm driving over 2500 RPM's. It's not a KNOCKING!!! but a quiet knocking. After it warms up it's almost not noticeable. Is this a "normal" thing? I have about 5K left on my warrantee so I want to make sure that I get everything check out before it runs out. Thanks for helping out the new guy!

Red Jay

does the knock also happen during idle or only while driving?

DPHC13

only while driving. And it really only happens when the RPM's are over 2500.

jaguarking11

Depending how cold it is, you should not have it go over 2k rpm or under 1k. The knocking your hearing is the valvetrain. The solenoids that adjust cam position make that noise not to mention the hydraulic lash adjusters and the hydraulic roller follower adjusters. I bet it sounds a bit like a diesel. Wait until your 1/2 through to normal temp before even going into the higher rpms.

I drive in cold weather and the 3v sounds like a tractor for the first few miles. I usually start the engine and let the rpm's drop to about 1100 before taking off. Then after that I keep a steady pace between 1k and 2k until im almost on the highway. Having a stick is good for stuff like this. I usually never go over 2k until the engine is fully warm, you know its warm when the heater is blasting hot. Put the heater in recirculate as well until its warm, I find it helps heat engine up quicker.

FYI if the outside temp is lower than 45F then it starts making most noise, the colder it is the higher the start up rpms will be. I have seen close to 2k rpm when the temp was in the 20's

Glenn

Do you hear it at all when you first start it? Stand outside the car and start it.

Imatk

Like Jaguar wrote... it's simple valvetrain noise... don't sweat it.

DPHC13

Glenn i only hear it when I drive it over 2k rpm's. From what you guys are saying it's got to be normal.

jaguarking11

Its normal to hear valvetrain noise on a 3v when its very cold. However once the engine warms up completely it should not make any valvetrain noise. Do not go over 2k when the engine is stone cold, its not a good thing for the engine, however you should not lug it either.

Everett

Recirculating heat inside the cabin will not help engine warm up faster ....it is ridiculous to even think that helps....

Imatk

Every engine is slightly different.

Mine had valvetrain noise for 27k miles and not a hiccup with the engine.

And yes turning on your heat will actually cause engine temps to go DOWN not UP.

In fact if you're ever overheating your car blast the heater... it will help.

slidejob

I have an 05' with 170K miles on it. When I start it cold it is very very quite. Once engine is warm I get a very light ticking noise coming from the cam covers. The injectors on this engine are very noisy, overall drivetrain noise is moderate, but you should not hear any engine noise, except exhaust or CAI, when you are driving.

Knocking generally is not good, unless you are describing ticking as knocking. Here is what I would suggest.

On your cold start listen to the engine through each wheel well noting the noise level. Then open the hood & stand over each bank & again listen to the engine. It should be very quite. If you hear any loud ticking or tapping get a long screw diver & put the driver side to the engine & the handle to your ear so you can isolate the noise. Repeat this procedure with a hot engine. Then if need be have some one hold the engine at a steady state 2-3K where you suspect the noise & again listen & isolate if needed.

I would be surprised with your low mileage if you have an engine issue, but it happens.

I would also suggest using a good full synthetic oil with regular changes.

Hope this helps.

Glenn

The first part of your answer was awesome.

jaguarking11

I didnt say it helps warm up faster but most people, (like me) I set the heat controls and forget them. When I come back and start my car I find the engine wars quicker when its in recirculate than taking in fresh air. Now ideally you turn the **** heat off altogether but I don't and I suspect most people don't either.

Sorry to be misunderstood.