i have a d16z6 in my 92 eg. Its been running a little rough lately. Im getting a bit of a rattle in first and second gear only. Also my revs when stopped like to jump around from 1-2000 when idling. They just go up and down for no reason.

Last, engine just sounds louder than usual. Sounds like belts and such. Still drives all good, just a few little issue's that im not sure about.

Again, none of this affects the driving (yet), its just kinda annoying haha. Any ideas would be great.

Was thinking timing belt/water pump/etc and shifter bushings could be it? Im at 195,xxx and no idea when timing belt was done....

EDIT: If this is in the wrong topic please move and let me know :D

 

Sounds like you need to do some basic maintenance. Flush the fluids, replace all the belts, new plugs, etc. The rattle could be a heat shield (on the exhaust or bolted to the chassis)...as shocking as it would be if they havent been removed already.

 

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Ive done the plugs and wires, dizzy, fuel filter. Im looking at getting the belts done soon. And i do have a fairly loud aftermarket exhaust, that could be part of the rattle. Its a very distinct sound tho, first and second gear only. If it was a heat shield wouldnt it do it all the time?

 

No, for some reason the heat shield usually rattles at a specific rpm range and it is more noticeable in the lower gears. Jack the car up and check them out.

 

The heat shield would rattle in different gears at roughly the same rpm, it's all about harmonics. The engine is producing sound frequencies all the way up the rpm range, and when you hit the natural frequency of the heat shield, it would rattle more. As for only doing it in the first two gears, that's a little odd, it should do it at roughly the same rpm in each gear.

 

its most noticeable in first and second gear at about 3000 rpm. Higher gears not so much, but may still do it sometimes.

 

Jack up the car and look. Look at everything. Whatever you suspect, check and double check.

 

Like everyone else is saying, jack it up and check it out.