Nestik

I got a 95 mustang GT (It's a convertible if that's needed!) I noticed whenever I go to hit the gas going up hill or occasionally when I accelerate my car makes a rattling noise.. not the kind of rattle you'd hear from metal on metal contact but it sounds like a fluid... I can only assume it's the gasoline making it's way to the engine but then again, my knowledge on my car only extends as far as page 10 of my Haynes manual... Now the odd thing is, if I hit the gas a little bit more while it's rattling the engine sounds like it SPRINGS to life with a bit of a roar and it sounds the way it should when running, granted my RPM's jump but that's about it. Is this normal or is this a problem?

Secondly, I noticed on occasion when I'm braking to stop my car will "rumble" not an audible noise.. but it vibrates much like a go-kart does. I can't imagine this is normal but like I said before I'm not very knowledgeable and this is my first car.

Third, Sometimes while I'm idling at a light or in a parking lot waiting for something the car will start shaking side to side and my battery gauge will jump back and forth and it sounds like the engine is kicking in then quieting down then kicking in again in a bit of a cycle. What could be causing this?

I know it's a lot all at once but I'd like to have someone with a lot more knowledge than myself take a shot at it and see if I can't get some answers! Thanks a ton ahead of time! Any and all answers are greatly appreciated!

dawson1112

Ok the rattleling going up hill when you give it gas is an indication of timing to far advanced or cheap gas. Check to be sure your timing is set to between 10-14 before tdc, fill up with some good premium gas like 92 octane. Some of these engines will be quite happy at 14 before tdc while others will run better at 10 or 12. The ratteling sound is probly pinging or what they call detonation caused by either the timing firing to far before the piston reaches tdc , the fuel mix is burning to fast caused by carbon deposits or hotspots in the cylinder usually on the exhaust valves, cheap low grade fuel like 87 octane because it burns faster than the higher grade 92, also a lean condition can cause the engine to get hot internally and the fuel mix starts to burn before the actual spark. Low fuel pressure can cause this also .
Now as for the breaking you probly need to replace the roters , alot of hard braking will cause them to warp and will cause a vibration either in the peddal or in extreme cases the whole car may vibrate .
The Idle is most likely a Idle AIR Control valve needing cleaned or replaced, Intake air temp sensor is dirty , or Maf is needing cleaned. Now the IAT and the MAF sensors also feed data to the ecm that it uses to adjust the air/fuel mix , if your ecm is seeing false data from either of these sensors it may try to lean out the fuel mix or fluctuate the idle . The leaned out fuel mix can also cause the pinging while accelerating up hill.

dawson1112

I would also like to add that the sn95 models use cast pistons compared to the older foxes that use forged pistons. The detonation is extremly bad for the pistons in your sn95 as it will quickly cause the piston or pistons to crack or get a hole in em. You really need to get that detonation problem under controll .