Three weird problems with my Supra...

[Alpha WereFox]

Hey. I'm getting kinda worried about my #1 possession. She's doing weird things lately that are confusing and worrying me. Like 2 weeks ago I got this random HP boost and I didn't do anything to the car that would give it such a boost. The only thing I did was putty up a dime sized hole in my exhaust. Sounds alot better but I doubt that's what did it. Another thing, I was driving around and instead of the exhaust sounding smooth as the RPMs went down like a constant bbaaaaawwwwww..... it let out these like tiny back fires I guess every half a sec, like Baw..baw..baww... (cheesy explaination I know). It sounds cool but it's probably not good. Last but least, when the car is cold or kinda cold, it hesitates at idle when I frist start it, the RPMs jump from like 400 to 600 RPMs. But once I rev it to like 3-4 grand and let off she idles fine. And it continues to idle fine after I drive and stop. I know some of you think I'm a "stupid ricer" but I do truely love my car and respect what I own. I'm really worried about all these weird things going on with her lately. Like if my motor is about to take a crap or something bad is coming. Maybe its time to put my 92 Shadow ES on the road earlier for winter and let the Supra sleep. Any help is apperciated.

Edit: My motor is a 7M-GE. Sorry I'm posting this right before I go to sleep. Move it if you can.

 

[supraman7mgte]

Any codes coming up? From my experience,the idle prob could be the the ISC,could be choked up with carbon. Check your plugs,proper gap and crap like that. Backfires i'm not too sure of,but others i'm sure will chime in.
You get to play detective,and get to figure out what the hell is going on.

 

[johnathan1]

I like your tails...lol. I guess imitation is the sincerest form of flattery.

Did you paint the center section?

 

[Alpha WereFox]

Yup they're painted.

 

[bluemk3]

first of nice to meet a fellow pa owner secondy i dunno why you d get a hp boost but i do know that runnign straight pipes will cause a little crakle in the exhaust liek small backfires ime does and im runnign a ddp test pipe and hks drager umm but it dosent sound like anything serious is wrong id just be happy for the gain haha i dunno not good advice haha sorry but nice to talk to anothe rpa owner as rare as it is to find one

 

[huntin5L]

maybe your clutch is slipping if you have a manual transmission and it is catching after a second and giving you this random hp gain.

 

[Jaguar_5]

The sputtering on downrev is probably from other holes in your exhaust, or a leak somewhere.

Also, it doesnt sound like a very good idea to rev it up to 4 grand right after you start her up, you need to let the oil warm up

 

[Alpha WereFox]

Clutch is new. And I hafta rev it or it stalls. I drive it everyday like 150+ miles and still no "major" problems.

 

[87nasupra]

My N/A does the same thing at higher RPM's as far as "hp boost". I got rid of my old worn out n/a exhaust and added a stock turbo exhaust with a test pipe. it sounds better, and i can hear myself while driving. It gives me that extra push at 3800 rpm's to redline. as far as the choking, it sounds like your isc has gone bad. check your plugs and timing for the "baw baw baww" and backfiring.

Good luck

 

[thevork]

Check your codes fist.

Idle stall is mostly because of a failing TPS or ISC valve. Check them first.
It's all in the TSRM.

Also check your timing.

As for the boost spikes, check for vacuum leaks. Vacuum leaks can cause that as well as idle stalling/hesitation.