jiga

Noticed a pretty weird sound yesterday coming from the engine. I was at a stop sign, turned off TC and O/D, put my auto down into 1st and went through the gears but only at about 75% on the throttle, not WOT. I was shifting it around 4.5-5k rpm's.
After 3rd when I put it into drive I hit around 4k rpm's in 4th and it started making this strange winding up noise from the engine. I quickly turned my O/D on and the vehicle switched to 5th and the noise went away.

Tried it again at another stop sign and it did the exact same noise. Very hard to describe, kind of whines I guess but from the engine area around 4.5k or 5k+ rpm's and only in 4th from what I see so far. Kind of sounds like a rev limiter I guess? I don't know... I'm a computer geek not an auto mechanic.

The vehicle is bone stock, and I also do need to replace my fuel pump per a TSD for that hesitation problem.

I pretty much baby drive this vehicle and rarely ever get on it.

Any ideas?

Thanks.

*EDIT*
Threads I have found that seem related to my issue.
https://mustangforums.com/forum/gt-s...-5000-rpm.html

Nuke

It's not the rev limiter which is electronic.

Does it make that noise at about 4k RPM in other gears besides 4th? It could just be a harmonic and you're rattling a heat shield or something. What happens if you're in neutral and rev to 4-5K?

jiga

I've only heard it in 4th gear so far and only when I was manually shifting my auto. I'll try it while I'm in neutral and see if I hear it. Still at work, so won't be till later this afternoon when I post back.

slidai

You should have bought a manual

jiga

Well I know I should have that's not news to me I wanted a manual, but I'm a family man and if my wife needs my car she needs to be able to drive it. I'd rather have her in an auto then jacking up a stick.

So, I wasn't able to test it today... starting pouring rain when I left work I'll try the neutral rev when I head out tonight. Rather not annoy the neighbors with a 4K+ rev.

Nuke

Yeah, wouldn't want the guyz in the hood to wish THEY had a Stang...

Daryl06

Hi I just burned up my tranny.A good way I found to check was when I was coming down a ramp(with a friend) from a downtown parking lot with walls on each side of my car.I stopped listened for a while to a little growling/grinding noise coming from around the firewall. Put it in neutral sound went away/ put it back in gear sound came back and so on.So when converter was under load I could hear the noises. I haven't got it out yet because it still drives like a stick car with a bad clutch. Ordering a TCI on Monday.I know we have different setups but it could be your torque converter so I don't think it would hurt to get a pro tranny shop to have a look. Don't like to give bad vibes so I hope you find your problem.

jiga

Revved up around 5k rpms in neutral, didn't hear the sound. Haven't really gotten it above 5k again and trying a 1st to 5th shift with it. Only have done that maybe twice. Other wise it runs fine through it's normal gears on Drive, even when I get on it a bit.

I may have just been hitting close to the red line on Thursday when I did that. I do still need to get that TSB about my fuel pump done though. I can feel the slight pause in acceleration when it's in low gear and I give it a bit, slight hesitation for a second.

Haven't heard any noises like that Daryl. Thanks for the heads up though.

jiga

After reading a few more threads with the type of sound I am hearing I believe it is detonation noise.

At lunch I got on it and it did not make the noise. When I left I got on it after making my turn and it did it again when going down a hill in 3rd and 4th gear. I made a video but I am waiting for it to hit my email... I did a second video from a 40 roll and once again, it did it.

I do not want to get on it anymore without getting this issue resolved. What can I do? I will try to post the videos as soon as they come into my email.

BTW, no mods on my car and I'm running 87 octane. Should I jump to 91?

BigDinTexas

If it is detonation, I would be hesitant to try to replicate it. My understanding of detonation is when the air/fuel mixture in the combustion chamber ignites before the spark plug does and before the completion of the compression stroke. This is not good and could lead to permanent damage. I don't think changing octane is going to help.

Someone else more knowledgable please confirm or correct me.

What does your engine temp look like when this happens?

Don