I have a 2000 Cherokee Sport with the 4.0 and was wondering how steady everyones tach is? Mine will fluctuate maybe 1/8 " which would equal maybe 50-75 rpm? Is this normal or is everyones tach rock steady at a certain rpm? I just bought this a little while ago and wanted to know what is considered "normal".

Thanks

 

steady as a rock here.

 

x2

 

Mine flucuates are well. Not even close to being steady.

 

Can you tell if the engine speed also fluctuates or just the tach?

 

X3

 

Mine fluctuates in a 3-4" arch, but holds steady if I keep my right foot steady.

 

Can't really tell.


I meant in park or in drive at an idle with foot on the brake.

 

Sitting at curb idle, every few seconds like clockwork the tach will jump a tad, then right back to steady. You could set your watch by it.

I'm pretty sure it's the electric fan kicking in ever so often.

 

I meant in park or in drive at an idle with foot on the brake.[/QUOTE]

at idle mine is still stuck, It does not move a bit.

 

my holds steady around 700rpm's @ idle

 

Cleaned my IAC today after reading this post and doing some searching. Found a good write up on how to clean the IAC. Took about 30 minutes. It was pretty dirty and carboned up. Jeep idles MUCH better now. Nice and smooth.

 

My tach fluctuates a little less than at odd intervals at idol, It could be just because the 4.0 is an MFI, and it adjusts its idle essentially - that's just my understanding, somebody call me on it by all means if it's complete bulls**t.

 

x4 gotta tap the gas pedal every now and then make sure its still working