Maybe bad questions but here

[cfl mike]

OK i have a 1998 sc400 and not really much modification done to it just cold air,exhaust,HIDS, Irridum plugs for the most part. I have a few problems that are really bugging me.

First off, when my car is cold or hasnt been started in a few hours i have to turn the key about 10 times for it to start and what it will do is just make a click then if you continue to hold nothing happens but the antenna goes down and the lights shut off till i let go of the key. My battery is charged and my alternator works. Could it be my starter? or ive had a suspison that my battery may not be putting out enough CCAs. Do you know the required CCAs to properly run the car?

Second im not sure if its my rear end, my transmission, or my pullys or something but when i hit about 50mph i get a shake in my car it kind of feels like the tired arent inflated right but i know they are and balanced and etc. If i hit around 70mph and listen closely and here this rinnnging sound but it has a pause in it and goes on agian like a rythm. sounds like its comming from between my engine and transmisson. Could i have bad mounts somewhere?

I havent really had the time or money to look into this do you guys have any suggestions?

 

[stevechumo]

...First off, when my car is cold or hasnt been started in a few hours i have to turn the key about 10 times for it to start and what it will do is just make a click then if you continue to hold nothing happens but the antenna goes down and the lights shut off till i let go of the key. My battery is charged and my alternator works. Could it be my starter? or ive had a suspison that my battery may not be putting out enough CCAs. Do you know the required CCAs to properly run the car?

If you're positive the battery is fully charged, then there's 1 click when you try to start the engine, the problem is 99% of your starter. If the battery is strong, the starter will crank and turn the engine. To be sure your battery is in good condition, take it out to an auto parts store like Autozone and have them test it for you. I don't remember exactly what's the minimum CCA the battery for the SC400 requires, but I'm sure a 450 CCA will start your engine just fine. I'd go for at least 650 CCA battery. I'm currently using a 900 CCA with 1000 CA battery to feed my stereo system.

...Second im not sure if its my rear end, my transmission, or my pullys or something but when i hit about 50mph i get a shake in my car it kind of feels like the tired arent inflated right but i know they are and balanced and etc. If i hit around 70mph and listen closely and here this rinnnging sound but it has a pause in it and goes on agian like a rythm. sounds like its comming from between my engine and transmisson. Could i have bad mounts somewhere?

This is not easy to troubleshoot. If you're sure the shake doesn't come from the engine, then it comes from the chassis or suspension. Do you have any clunking noise when you go over bumps or dips? Does the shake come between shifts?

Try to accellerate from 0 to 70 mph on a smooth surface & quiet street and so that you can listen to it.

 

[Jake Breyck]

just wondering where in florida you are? im guessing orlando from your name.

 

[cfl mike]

no im in melbourne Florida and it doesnt make any unusual noises when shifting only when going a constant high speed i cant tell if its coming from the engine or the transmission really but it sounds like its coming from where the tranny mounts to the engine. maybe bad mounts? no i dont get any unusal noise from going over bumps. Sometimes it feels like the bump is bigger than it really is. I tested my car today actuly and i can fell then bumping even going real slow but it almost feels like there like a square part in the tire but i know thats not the case

 

[rx7 s1 1uz]

Second im not sure if its my rear end, my transmission, or my pullys or something but when i hit about 50mph i get a shake in my car it kind of feels like the tired arent inflated right but i know they are and balanced and etc. If i hit around 70mph and listen closely and here this rinnnging sound but it has a pause in it and goes on agian like a rythm. sounds like its comming from between my engine and transmisson. Could i have bad mounts somewhere?

I havent really had the time or money to look into this do you guys have any suggestions?

the rythm sound you are hearing can come from your tires check if the are wearing even in side and out and also check if the is any scalloping (tire got like wavy fell to it). are you using snow tires by any chance

 

[Ursus]

The strange shake could be the drive shaft bushings or something is out of balance or mis aligned.

 

[cfl mike]

no im not using snow tires but i have the wide version of the sc430 rims. my tire guy said my tires were balenced and my tire pressures seem to be good and theres no unusal wear. but thats what it does feel like and thats what i thought it was at first. is there such things as wheel weights? to help balancing? I need to check my suspensions and bushings but i dont think they would create this odd shake