Multiple Car problems

[KinaGrannis]

Hey guys new to the forum. Ever since I got my 240 I've had some minor problems that I haven't had time to address.
I was able to fix a couple but the remaining ones I have no idea how to address as I am not that tech savvy with cars yet.

The rpm spikes when I floor the pedal. If I slowly press on the gas pedal nothing out of the norm happens, it's only when I floor it. I believe its because I need to change my clutch? Not entirely sure but the clutch is kinda worn out.
Also, the speedo has a similar problem. If I gradually go faster, then the speedo will be correct, however if I press on the gas pedal more, the speedo would spike up and tell me I'm driving at 110 when I'm probably going around 75 on the freeway.
And my last problem is the car dying when I turn it on. Every now and then when i turn on the car the rpm would go up and then fall back down to 0 while making a light shriek noise. This only happens occasionally but whenever I believe it's gonna die all I have to do is give it a little gas and it'll idle normally.

Thank you and any advice/help would be much appreciated

[KinaGrannis]

bump? any help?

[Eramo323]

possible speed sensor problem on the cluster, search for any vacuum leaks on the last problem... i don't get the first one

[millsaps]

sounds like a diff problem. do you have an lsd?

[rcdad123]

clutch is slipping. thats why when you give it a lot of power, the rpm goes up but not the speed of the car.

[jacobzking]

Originally Posted by rcdad123

clutch is slipping. thats why when you give it a lot of power, the rpm goes up but not the speed of the car.

+1 for the clutch.

[KinaGrannis]

Well I kinda figured it was the clutch but I just wanted some verification. My main concern is the engine sometimes dying when I turn it on.

I do not have an lsd

I've searched for vacuum leaks and do not come across any.

[KinaGrannis]

bumppity bump

[epik1]

idle control valve?Starter? alternator? -regarding your dying issue.
I would guess speed sensor for your speedo problems.

Change your clutch first see what that fixes.

[freeagent3117]

It sounds like a clutch to me also but it doesnt explain the speedo going up also. As that reads the speed via the transmission. The slipping clutch wouldnt affect the tranny speed.

Are you sure its not burning out!! LOL just kidding

[KinaGrannis]

Ok so I replaced my clutch and the rpm no longer spikes. Thanks a lot
However I'm still having idling problem.
I could turn on the car and sometimes the rpm will just fall back down and die. I can counteract this if I feel like the car is dying by stepping on the gas and forcing the rpm but. By doing this, the rpm will idle normally. However, I feel like if i continue to do this, soemthing terrible will go wrong
any help?

[jacobzking]

Either vacuum leak or idle air control valve. Check for vac leaks first. You can also adjust the idle air control valve.

[KinaGrannis]

thanks guys for all the feedback but i have a more urgent question at hand

so my car used to die because of a grounding issue but after i resolved that, I realized that my car sometimes didn't start up. But it wasn't a battery problem because eventually I could turn the car on after a few turn of the key.
So I've searched some and come to the conclusion its either the starter or ignition switch or just the ignition cable
My question is how do i determine which one without having to buy all of them because i'm kind of on a college budget.
If i turn the key once, the lights come on but I kind of notice that I have to turn the key hard and the car will start
Advice will be much appreciated. thank you

[KinaGrannis]

bummp to the top

[idlafie]

Take the starter out & take it to Pep Boys, Autozone or O'Reiley's autoparts & have them test the starter for you. They will be able to tell you if the starter is good or not. What year is your car?? To check the ignition switch on a S14, (95-98) pull the steering column cover off. Directly opposite where you insert your key is a wiring harness that is held in by two screws. Remove these two screws and the plastic ignition switch and harness come out. Place a small screwdriver into the plastic slot on the switch and turn it. You'll need a voltmeter to test the switch as you turn it. Best you get your hands on a Factory Service Manual and follow the troubleshooting methods listed to test for a faulty ignition switch. Oh...while you are at it, get some baking soda and water & clean your starter wires running from the battery to your starter. You get enough crud buildup on the wires, the wires won't be able to get enough current to your starter to start the car.
Anyhow, hope this helps...
ID

[KinaGrannis]

Great advice, but my car is a 1992 240sx. Will the same procedure apply to s13s?
I am really hoping that the problem is either the ignition cable or ignition switch

[KinaGrannis]

bumpbumpbump

[KinaGrannis]

Hey guys I've fixed most of the problems thanks to you guys except for the final problem. A symptom that I forgot to mention is that usually when I step on the gas pedal and let go, with the car in neutral, the rpm would go up and as it goes back down, it would stay at around 1400k not really sure the exact number, for a second or two before it goes back down to idle

[wangan_cruiser]

check your throttle cable to see if it sticks. or check the idle screw and re adjust it