ok, im not sure wuts going on but recently my car makes a very metallic sound when under load and low rpms. say im going up a normal hill and its just me in the car, my car will make a very loud metallic slap sound, my friend said it was detonation however im not sure because i put my car in my garage, popped the hood and pulled the throttle quickly and it would make a VERY loud metallic slap sound at first until the load was gone, it never did this before i got the new valve train and rebuilt my motor.

also i was at home depot today and i started my car and right when i started it up it was EXTREMELY loud and vibrating like crazy!. i tried to drive but it felt very bad so i pulled in the next spot to me. tried to make it stop but it wouldnt.. RIGHT when i gave up i siad ok i have to get home so i tried to drive it, then all of the sudden it was smooth again out of nowhere, very strange, any ideas please? and it wasnt running on 3 cylinders because i checked by pulling each plug out while running and it would run different(bad) each time... could this be a sign of maybe one of the rods coming off? cuz i just did this rebiuld. thx let me know!

 

ne one?

 

Sounds you need a valve lash adjustment

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by WalkerGSR1 &raquo;</TD></TR><TR><TD CLASS="quote">Sounds you need a valve lash adjustment</TD></TR></TABLE>

 

It sounds like detonation. Perhaps you purchased the wrong fuel. Does your knock sensor work. i.e. have you modified your ECU?

 

i do use 91 100% of the time. the ecu is a modified p28 from JKTUNING on here and it HAS been tuned by Whitfield racing. not sure if the knock sensor is out

 

P28 ecu doesnt support knock sensor, so its probably disabled.

 

that sux, i guess ill take off oilpand and windage tray and make sure everything is still to torque spec. thx for info guys .. one more thing. my underdrive pully seems to wobble a slight bit.. doesnt seem good. thx

 

If it was detonation or knock it probably wouldn't be happening while the car is sitting in the garage under 0 load. Pull your plugs and look for any signs of detonation. Also check on your pulley you said it had a "wobble". That can't be good for engine harmonics, and possibly at the rpm range you're speaking of.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AnthraxVX &raquo;</TD></TR><TR><TD CLASS="quote">i do use 91 100% of the time. the ecu is a modified p28 from JKTUNING on here and it HAS been tuned by Whitfield racing. not sure if the knock sensor is out</TD></TR></TABLE>

The station could have sold you the incorrect fuel. As stated above, the P28 does not have knock sensor support.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sack Master &raquo;</TD></TR><TR><TD CLASS="quote">Pull your plugs and look for any signs of detonation.</TD></TR></TABLE>

 

I would say put the stock crank pulley back on.

Also check your valve lash clearances again. The first time I did mine, I screwed it up and the engine sounded like a diesel. I checked and checked and checked, and a friend came over and checked several times, and we all missed it. Finally about 4 days later I checked again and found one valve that was sitting at about 30 thousandths instead of 7 thousandths (i.e. over 4 times the clearance specified). I tightened it up and it ran fine ever since.

 

k. will do. thx

 

yea but see that still doesnt really answer why my car was vibrating like crazy.. hopefully nothing to do with tranny or flywheel or i have to pull that bitch out. haha

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AnthraxVX &raquo;</TD></TR><TR><TD CLASS="quote">yea but see that still doesnt really answer why my car was vibrating like crazy.. hopefully nothing to do with tranny or flywheel or i have to pull that bitch out. haha</TD></TR></TABLE>

When that one exhaust valve was way out on mine and it sounded like a diesel at idle, I seem to remember it vibrating pretty bad then, also. Who knows. One problem at a time, see if you can fix that sound first and then if it still vibrates deal with that.

 

It could also be both valve clearance and low grade fuel than required

 

well. i know my fuel is good and i will check valve clearence next morning . thx i will keep u all posted.

 

you sure its not your injectors? my buddys dsm was having that trouble and we thought it was rod knock, but it only happened under load. it turned out to be extremely loud injectors.

 

mine idled bad when the valves were all whakked out. got a valve job, rough idle is gone and it runs like a champ. i had the same metallic sound at about 3700-4000rpms. dont have ti anymore

 

yea. i have valve job done by Portflow and COMPLETE supertech valvetrain. im positive its a metallic sound not just injectors. ill figure it out im sure