Weird chirping noise, tach needle flickers

[tiggs]

Ok, so here's what's happening: 93 240sx Hatch with a 95KADE

Last friday I started hearing this small chirping noise between 3500-4500 rpm. Unfortunately I didn't have any time all weekend to pop the hood and take a look. Since then I've had to drive the car around 200-250miles. As of now, the chirping noise starts at around 1700rpm and continues to the rev limit. It's a very annoying noise. It doesn't sound like a belt, my of like an unballanced pulley? Like it's rubbing or something.. I dunno...

Now at the same time this started, my tach decided to start being funny. At the same 3500rpm the tach would flicker up to around 4000rpm. Like a nervous twitch. As of today, it will flicker anywhere in the range that the chirping happens. I'm guessing these haveta be related.

I'm trying to narrow down what might be wrong. I wont have time to pop the hood until this evening (I really need a second person there to rev the engine so I can try and fine the location of the chirp) so I wanted to see if you guys had any ideas on what I should be looking into when I finally get the chance to check it out. I'm going to try and get a sound clip tonight, maybe a short vid to show how bad the tach flickers.

Does the tach signal come from the alternator? I know in some cars it does but I don't know about ours.

Thanks for any help you can give. If you frequent other 240sx boards you'll probably see this thread in there as well, lol.

[aznpoopy]

you can rev the engine while under the hood by opening the throttle by hand.

good luck pinpointing the noise

[tiggs]

you can rev the engine while under the hood by opening the throttle by hand.

good luck pinpointing the noise

Haha, good idea, stupid me. I knew that too it just slipped my mind. doh. :smash:

[aznpoopy]

btw i think the rpms are read directly from the ECM. no clue how the ECM derives the rpm signal though... maybe one of the gurus will chip in.

[tiggs]

Well, when I got to work this morning I noticed when driving really slow my steering wheel had some pull on it..
Tonight I get home and my brother and I take a look, I rev the engine, we can't really tell where the sound is coming from except that it's probably the belt in the front. Anyway, I get in and turn the wheel and we hear it chirp. I keep turning it and my brother notices the power steering pump pulley stutters. the belt still goes over the pulley but it slows down and the pulley pretty much stops, then goes, stops and goes. The noise seems to be like a bearing rubbing. Fluid is full btw.


So I guess it's time for a new power steering pump huh? Anyone know where I could get one for a decent price? From what I've seen so far online I'm looking at around $150 give or take $20

edit: also, I have a 95KADE in my car... do I pickup a 93 pump or a 95? Looking at the part numbers there is a difference

[aznpoopy]

you can get a pw pump for like $25 bucks+shipping

car-part.com

[tiggs]

Yeah I checked car-part and found a couple in my state for like $50.. But I'm wondering.. is getting a used one really that safe? Honestly, I can afford the $150, but I'd rather find a better deal. Sure I'd love to save a ton of cash, but I'm really looking for reliability.

So my question is, can I count on a used one? If it's a safe bet to get a used one then I will.

[aznpoopy]

thats really a matter of luck...

if you got the budget for it, go with what you feel.

btw check the powersteering lines under the car... i have a feeling they are kinked.

[tiggs]

btw check the powersteering lines under the car... i have a feeling they are kinked.

VERY VERY good idea

I will take a look in the morning. Maybe the pump is starving therefor rubbing.

Maybe during the engine swap out (only about 2 months ago max) something coulda become kinked up.

Great idea. I'll check on it. I don't wanna get my hopes up too much though just in case, haha.