2G Grinding noise after starting 97 gst

[97gstproject]

I have a grinding noise coming from the driver side of the engine bay. It only happens the first time i start driving after start up when i get to about 5 mph. If i come to a complete stop and start driving again the noise doesnt come back as long as i dont turn the car off. When i reach about 5mph its a very uniform grind the lasts about 3 seconds and doesnt matter if i start in 1st or 2nd gear. Ive had 3 "mechanics" listen to it and they either dont know or say its the brakes WTF Please help!

Bone stock '97 gst, 5spd

 

[RedVengeAPX]

I would have said brakes also, if it stops and doesnt come back until you turn the car back on have you let the car cool down or is it right after you shut it off and start back up. I would check all the belts and pulleys over there and maybe even see if your low on power steering fluid

 

[97gstproject]

If i turn it off and imediately start it back up and start driving it grinds, doesnt seem to matter wether its cooled down or not. I have had the driver side front wheel off and the brakes LOOK fine, but i didnt check the caliper piston or any of the hardware, good pad life and no grooves in the rotor etc.

Edit: Now that you mention it, i recently noticed my alternator belt had 2 of the ridges on one side worn down to nothing, so i replaced it and the new one did the same thing and ended up snapping, possibly a warped or bent pully? or bad bearing?

Thanks for the suggestions!

 

[luv2rallye]

Did someone recently have the water pump pulley off and put it on backwards? Common case of destroying alt belts.

 

[97gstproject]

Possibly, but it would have been before I bought he car. Is there anything in particular to look for to tell if the water pump pully is backwards? And could this somehow be causing the grinding noise?

 

[luv2rallye]

Probably not the grinding but when you mentioned the belt problems I thought of the pulley (although you get a squeeling with the pulley). Still it's just a look-see to check if pulley is on backwards:
http://www.dsmtuners.com/forums/new...n-out-water-pump-pulley-go.html#post151166499

 

[97gstproject]

You're absolutely right! The pully is on backwards. Thank you, that's one problem solved. If anyone has any other suggestions for the grinding let me know.

 

[Sicotic]

Did someone recently have the water pump pulley off and put it on backwards? Common case of destroying alt belts.

been there. done that. common rookie mistake

 

[97gstproject]

Has anybody heard of anything similar to the grinding situation I described? I'm leaning towards something drivetrain related but I know little to nothing about transmissions. I'll be pulling the motor out this weekend hopefully so ill have easy access to the tranny. If anyone any ideas of anything I should look for let me know.

 

[luv2rallye]

Before doing something as drastic as pulling the motor I'd exhaust all other possibilities first. Does it still grind when you push in the clutch, or when putting it in neutral, or lightly tapping the brakes? How about when going slowly on turns or in tight circles (tests CV joints)? How about when you turn engine off and coast?

It sounds more to me like brakes/calipers though. Especially since it only happens when moving. Lift LF wheel off and check for excess bearing play by wobbling the wheel left/right and in/out at top and bottom. Then remove wheel and pads, calipers, rotors, and inspect them all. Are the pistons frozen? Pads glazed or wearing unevenly, rotors damaged?

 

[97gstproject]

I'm pulling the motor anyway, I have some other work I'm doing to it. The noise literally only happens that one time after starting and getting to about 5 mph, with or without touching the breaks or turning the wheel. I've already checked the breaks and wheel bearings recently but ill check again and go a little more in depth and remove the caliber to check the piston. Once I get the water pump pulley flipped back around and the belt put back on, ill try to get a recording of the noise. It almost reminds me of the sound the automatic Chrysler transmissions make when down shifting but a little harsher.

 

[97gstproject]

I got it running again and the grind has surprisingly disappeared, and now theres a clicking/hissing sound coming from the alt or ps pump area. I'm leaning towards the ps pump since the alternate is almost brand new. No performance issues from either one though. Anyway, As I said, ill be pulling the motor to replace all the gaskets and seals to fix the numerous oil leaks, does anybody have recommendations as far as cheap upgrades or mods while I'm at it? I'd like to get up around 350 HP without spending more than say $500, if possible. Suggestions are greatly appreciated