New Car help - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Armysweitzer · 08-05-2003, 07:19 PM

Hey guys and girls, hope all is well!

I just bought a 1990 240SX Fastback with 80K... Great car with only minor issues. Ill post some pics for you guys to flame my car

.

However sitting in my car the other day I turn on my beloved AC which works awesome. When I do that my car shakes and I hear a rattle, Both are intermiten. I look under the car and see a metal thing around the exhaust (resignator

) which is making the rattle.

After I turn it off i get idle surges that range from 500-1500 RPMs that feel like the car is about to shut off. After about 10 seconds they stop and the car is normal again.

Ok Nissan Gods

how do I fix this crap?

Thanks a ton for any response and I will post some pics after I get them developed.

twitchy · 08-05-2003, 11:53 PM

not too sure how to FIX it although some noise and unsmoothness from the engine is normal when the AC is on..

take it in if it gets bad

mine does it too..shakes, rattles a bit. AC is a big drain on the motor

misnomer · 08-06-2003, 12:28 AM

that rattling thing sounds like an exhaust heat shield. If it is directly under the drivers seat, it is probably the catalytic converter heat shields rattling.

AC will cause the idle to change on any car, it's more noticable on smaller engines. I wouldn't stress it too much unless it is way out of whack.

Replicant_S14 · 08-06-2003, 07:48 AM

Could just be a tune up issue. The A/C has an "idle up" circuit. Maybe it's just having a tough time smoothing the idle. It's probably no biggie. If you haven't done it already, tune it up and run some fuel injector cleaner through it. At least then you'll have a base to start from.

I don't know if s13s are the same but my 95 has a real cat, a second cat (that isn't really a cat) and a resonator. The "fake" cat is directly below the drivers seat and it rattles like crazy. It's basically a shell with 2 plates welded inside on the top and bottom. The plates are what rattles. I'm going to fix it by welding up a straight pipe to replace the fake cat all together.

Good luck with the new ride.

Armysweitzer · 08-06-2003, 08:07 AM

thanks a bunch guys. Ill figure something out, its no biggy just i hate rattling noises (im sure you all know what i mean). Yeah the ride is pretty clean i just gotta bondo and paint the rear trunk where i ripped that crappy spoiler off.

Thanks again and pics coming soon.

Armysweitzer · 08-07-2003, 05:56 AM

well I was driving around yesterday and I hear that lovely scraping noise. Guess what it was!!!...I get home and see the heat shield barely on my Cat. I had no choice but to take it off. Are there any reasons why this is bad or i should put it back on? THanks a lot

**mrmephistopheles** · 08-07-2003, 06:24 AM

just leave it off and don't park on high dead grass after driving.

Armysweitzer · 08-07-2003, 06:47 AM

oh jeez

.... "officer I swear to god that fire wasnt my fault, Blame Nissan!"

*crioten* · 08-07-2003, 12:10 PM

i took off my heat shield when i put my exhaust on, not sure why i did it....

but yeah, it really isnt a problem, its not as if high grass is going to catch fire by just only touching your un-heat sheilded area, if it does catch fire, you will be able to drive away faster b/c that mod adds 30hp, and has less drag

syco3d · 08-07-2003, 01:18 PM

Quote:

Originally posted by crioten
you will be able to drive away faster b/c that mod adds 30hp, and has less drag

...you forgot to mention the mAd tYtE weight reduction

08-05-2003, 07:19 PM	#1
Armysweitzer Leaky Injector Join Date: Jun 2003 Location: Wakefield RI Posts: 72 Trader Rating: (0) Feedback Score: 0 reviews	New Car help Hey guys and girls, hope all is well! I just bought a 1990 240SX Fastback with 80K... Great car with only minor issues. Ill post some pics for you guys to flame my car . However sitting in my car the other day I turn on my beloved AC which works awesome. When I do that my car shakes and I hear a rattle, Both are intermiten. I look under the car and see a metal thing around the exhaust (resignator ) which is making the rattle. After I turn it off i get idle surges that range from 500-1500 RPMs that feel like the car is about to shut off. After about 10 seconds they stop and the car is normal again. Ok Nissan Gods how do I fix this crap? Thanks a ton for any response and I will post some pics after I get them developed.

08-05-2003, 11:53 PM	#2
twitchy Zilvia FREAK! Join Date: Apr 2003 Location: Ontario Posts: 1,579 Trader Rating: (0) Feedback Score: 0 reviews	not too sure how to FIX it although some noise and unsmoothness from the engine is normal when the AC is on.. take it in if it gets bad mine does it too..shakes, rattles a bit. AC is a big drain on the motor __________________ Who the hell needs a sig anyhow

08-06-2003, 12:28 AM	#3
misnomer Nissanaholic! Join Date: Jul 2001 Location: Nevada Posts: 2,293 Trader Rating: (0) Feedback Score: 0 reviews	that rattling thing sounds like an exhaust heat shield. If it is directly under the drivers seat, it is probably the catalytic converter heat shields rattling. AC will cause the idle to change on any car, it's more noticable on smaller engines. I wouldn't stress it too much unless it is way out of whack. __________________ Rowsdower saves us and saves all the world!

08-06-2003, 07:48 AM	#4
Replicant_S14 Zilvia Junkie Join Date: Jul 2002 Location: Cabbagetown Posts: 467 Trader Rating: (0) Feedback Score: 0 reviews	Could just be a tune up issue. The A/C has an "idle up" circuit. Maybe it's just having a tough time smoothing the idle. It's probably no biggie. If you haven't done it already, tune it up and run some fuel injector cleaner through it. At least then you'll have a base to start from. I don't know if s13s are the same but my 95 has a real cat, a second cat (that isn't really a cat) and a resonator. The "fake" cat is directly below the drivers seat and it rattles like crazy. It's basically a shell with 2 plates welded inside on the top and bottom. The plates are what rattles. I'm going to fix it by welding up a straight pipe to replace the fake cat all together. Good luck with the new ride. __________________ Rules of Boozing #10: Do not make eye contact with the bartender if you do not want a drink.

08-06-2003, 08:07 AM	#5
Armysweitzer Leaky Injector Join Date: Jun 2003 Location: Wakefield RI Posts: 72 Trader Rating: (0) Feedback Score: 0 reviews	thanks a bunch guys. Ill figure something out, its no biggy just i hate rattling noises (im sure you all know what i mean). Yeah the ride is pretty clean i just gotta bondo and paint the rear trunk where i ripped that crappy spoiler off. Thanks again and pics coming soon.

08-07-2003, 05:56 AM	#6
Armysweitzer Leaky Injector Join Date: Jun 2003 Location: Wakefield RI Posts: 72 Trader Rating: (0) Feedback Score: 0 reviews	well I was driving around yesterday and I hear that lovely scraping noise. Guess what it was!!!...I get home and see the heat shield barely on my Cat. I had no choice but to take it off. Are there any reasons why this is bad or i should put it back on? THanks a lot

08-07-2003, 06:24 AM	#7
mrmephistopheles Magnanimous Justice Distribution Service Join Date: Mar 2002 Location: BFE Age: 23 Posts: 14,372 Trader Rating: (9) Rides Gallery: mrmephistopheles Feedback Score: 9 reviews	just leave it off and don't park on high dead grass after driving.

08-07-2003, 06:47 AM	#8
Armysweitzer Leaky Injector Join Date: Jun 2003 Location: Wakefield RI Posts: 72 Trader Rating: (0) Feedback Score: 0 reviews	oh jeez .... "officer I swear to god that fire wasnt my fault, Blame Nissan!"