Rattling Noise Occurs @ 50%+ Throttle

[onefstsnake]

Well I just had some work done to my car within the last week.

Timing Adjusted, Trans Seal Replaced, Belt Change, Coolant Flush.

And Now the car makes a very distinct rattling noise when 50% + throttle is applied. The car only makes this noise when the car is in gear and driving...

When the dealership replaced the rear seal on my T5 they didnt say anything about adding fluid... Would low trans fluid cause the noise?

Seems to me like it would be the trans... (rattles only when in gear)

Ive also noticed a poping noise w/ a slight "bump" of the rear end when shifting from 1st to 2nd while at a stop.


Any help would be great. Thanks!

 

[RacEoHolic330]

does the rattle happen in every gear?

 

[onefstsnake]

Im not sure about 1st and 2nd b/c I cant get on it too hard or it spins.

But it does in the other 3.

Please dont tell me the tranny is about to go...

 

[sunil6784]

Detonation? What did they set the timing at? What octane fuel are you using?

 

[onefstsnake]

They told me they didnt know what they set the timing to. I believe the set it back so it would pass emissions. Im running 87 octane.

I dont think its detonation... Sounds like a metal/mechanical sound.

 

[retro50]

I hope you didn't pay the dealership for the work that was done! They couldn't even tell you where they put the timing at? I'd buy a light and check it myself. Sounds like detonation to me! especially with 87 octane.

 

[onefstsnake]

the guy I talked to wasnt a Tech. He was just the cashier guy...


Whats a good place to set the timing at for 87 octane?

Also, how come the engine doesnt make the noise in neutral? No load?

Im 98% sure its not detonation...unless detonations sounds like metal rattling.

 

[Black1987Stang]

Mine had a noise right around 65%-75% throttle . It was weird cuz it wasnt at full throttle or at a certain load or anything like that only at a certain throttle position. it was a noise that sounded like somone hitting the inside of my lifter galley with a hammer At first I thought it was my collector/header hitting the firewall (sounded like it anyway) but i have plenty of clearance there. Now about a month after it got much worse and now I know it is my lifters and im changing them this weekend

 

[onefstsnake]

So you think its the lifters?

And if it is, why would it suddenly start making this noise?

Would the tranny make that noise if it was low on fluid?

 

[timewarped1972]

if they had the drive shaft off make sure they tightened the bolts, check your u joints as well......and as mentioned above the timing, detonation can sound rather metallic and it will normally only do it under load...if you only started noticing this stuff after you got it back from them, you need to re check everything they did.....lol, i know that sucks but.......gotta do it

 

[onefstsnake]

Wouldnt you need to add tranny fluid if you removed the driveshaft to replace the seal?

Ill check the driveshaft and timing tomorrow.

How easy is it to check the timing?

 

[HISSIN50]

I would explain to the shop what is going on (that this just happened after they had the car). If willing, have them look over everything or even go on a test drive with you.

Good luck.

 

[timewarped1972]

first you need a timing light, if you don't have one, buy one, you'll need it sooner or later anyway.
try a search in here on how to set the timing i'm sure theres a full how to on it thats better than i could describe.......but you'll need a timing light, you need to follow the instructions on hooking up the timing light ( usually hooks to the battery, then the clip on the light hooks to the #1 plug wire) then theres a grey spout plug on a wiring harness in front of the distributor, pull that out, dont lose it, start the car and then shine the light down on the balancer, youll be shining it from the passenger side of the car....down toward the crankshaft pully. theres a pointer on there, and there should be markings on there but, you gotta know how to read them, and sometimes they arent real visible.....
if you have no idea how to do it, search in here and buy a manual, you'll be using it often...
note, and i agree with what hissin50 said, but you'll be better off in the long run if you learn this stuff for yourself so your not at the shops mercy...........

 

[HISSIN50]

As requested, how to set timing

Tim (Stang22) also has a nice article on his drool site, but I can never get from the main page to his page, so I cant find it. Besides, I start lookin at the pretty pictures and forget why I came.

Good luck.

 

[Mike92GT]

Kinda sounds like detonation to me too. Try putting some octane boost or a few gallons of premium fuel in it and see if it goes away. Stock 5.0's usually run best with about 14 deg. of timing, but you would have to run premium to avoid detonation. If your running 87, I wouldn't go more then 10 deg. of timing

 

[Black1987Stang]

So you think its the lifters?

And if it is, why would it suddenly start making this noise?

Would the tranny make that noise if it was low on fluid?

Im not saying its ur lifters, but thats what was going on with mine. I would say its got to do with what they did. I would talk to the dealership see exactly everything they did and tell them ur problem, i doubt ur trans could be the problem. I would try putting higher octane gas in it, and pick up a timing light and learn to do it urself. Its really easy

 

[onefstsnake]

Well I just pulled the #1 and #2 Spark Plugs. They look whitish/brown on the top and have a slight smell of oil, but not wet at all.

Plugs seem fine... But Ill go put $5 of 93 and see if that helps.

Getting a timing light in the next few days.

10* ok for 87octane?

 

[tunedin302]

Drive the car forward and stop. Then put the car in reverse and see if you hear the clunk. If you do then it is likely a u joint or a loose driveshaft. If they had the trans out then I would start checking some obvious stuff under the car. Often times people forget to use loc-tite on the d/s bolts and they loosen up. Otherwise, they set your timing wrong and it is detonation that you are hearing.

 

[onefstsnake]

Do I need a special timing light or will the $30 Cheapo from Advanced Auto Parts work fine?

 

[timewarped1972]

that should work, i have a cheap sun pro i been using for years......you don't need the fancy dial back digital ones for basic stuff...they are cool though.....
the biggest problem you may have is the balancers tend to get dirty over the years. make sure you clean it off real well, and you may need to take a majic marker or something and mark the degree marks you need to see...although if they supposedly just checked the timing it should be visible...