the other day i went to brady,tx,which is 3 1/2hours from where i live, well when i got to brady, my car started acting weird.first i started hearing this sound coming from the back and it sound like a crackling sound it happen everytime i hit 3000rpm and when my magnaflow magnapacks got loud and thats when i would hear the sound,so what could have that been.Its gone now but im just wondering what it could have been. 
The second thing to happen is after i got off the car i let it sit for 30mins and then i started it up again and my rpm needle started to bounce around 500rpms and 1500rpm for about 30sec and then stop at 1000rpms and that was that.IT only happen that one time
Two other little things is when i was coming back home my temp was in the middle but its usually at 1/4 of the temp.could it have been the heat?The other thing is i have a mac orh and was wondering is it ok to smell gas sometimes.
The second thing to happen is after i got off the car i let it sit for 30mins and then i started it up again and my rpm needle started to bounce around 500rpms and 1500rpm for about 30sec and then stop at 1000rpms and that was that.IT only happen that one time
Two other little things is when i was coming back home my temp was in the middle but its usually at 1/4 of the temp.could it have been the heat?The other thing is i have a mac orh and was wondering is it ok to smell gas sometimes.
