Our Community is 940,000 Strong. Join Us.


problum w/ 92 3000gt need sugestions and HELP


grafixx3000gt
03-08-2007, 10:26 PM
i dont really know much about cars but my mechanic is almost out of ideas! the power of the car got worse and worse with in 18 mo. and now, while ideling it surges.when warm and in drive it doesnt wanna go. i noticed it felt like it was missfireing some times awhile ago but it has gotten so severe that i had to pump the gas just so it wouldnt stall when i pulled out. i had to keep pumping the gas till i could buit up speed to about 25mph(which took about 3 blocks!) after my mphs reached 20-25mph it would accelerate a littel faster but keep putting or missfireing. even at speeds of 75 or more. these are some of the things the mechanics have rulled out:its not, fuel pump, mass air flow center,ambiant temp gauge,throdl sencer, spark plugs & wires, exhaust blockage... when its hooked up to the computers it doesnt read anything wrong. if any one has any suggestions please let me hear them.

3kvr4
03-08-2007, 10:30 PM
hmmm, how many miles are on your car?

3kvr4
03-08-2007, 10:32 PM
also you can open ur ecu and check for leakin caps.

AutostradaVR4
03-08-2007, 10:45 PM
iss? iac? compression test?

grafixx3000gt
03-08-2007, 11:08 PM
it has about 109k miles on it. the mechanic didnt specify in that much detail, plus i dont know alot about cars,but he is a reputable mechanic and he is very thuro. im assuming he has checked all the obvious possibelities,hes the second mechanic to have this car for over 4weeks.

Linebckr49
03-09-2007, 01:33 AM
sounds like you have several problems.

misfiring: PTU (power transistor unit), coil pack, ECU (engine control unit).

idle surge: ISC/IAC (idle stepper control/idle air control), check throttle cable tension, FIAV (fast idle air valve).

no movement when warm and in drive: i assume you have an automatic? end clutch, TCU (transmission control unit), tranny fluid.

hopefully some other guys will chime in. Hotshot8792 is well versed with the automatic transmissions.

Igovert500
03-09-2007, 03:30 PM
Alright, well first off I'll say this. While the mechanic maybe a great guy and completely honest...it doesn't mean he knows squat about our cars. They can get pretty complicated at times, and some mechanics wont even touch them. Think of it this way...just because you can program your vcr, doesn't mean you would try to program software on your computer. Anyway, I'll just start tossing out ideas as they come. Most of these, you could probably do yourself with a set of socket wrenches and the ability to follow directions.



1) When the computer doesn't show any error codes, but the car is screwing up that bad, I would start to wonder what shape hte computer (aka ECU) is in. The 91-93s are NOTORIOUS for having leaking capacitators. It's a $5 preventative measure that we try to get everybody to do beforehand, but some people just don't know and end up getting their computer boards fried. There is a section on it in our FAQ (which I highly suggest you read)

Removing and Inspecting the ECU (http://www.stealth316.com/2-ecmremoval.htm) If this is your problem, don't spend a grand at a dealership for another ECU, they can be replaced or repaired for under $300...I picked up a replacement ECU for $100 shipped to my door.

Next thought, as Linebckr mentioned the misfire maybe from the PTU (http://www.stealth316.com/2-pwrtransunit.htm) or coils (http://www.stealth316.com/2-ignitioncoils.htm).

If your fuel filter hasn't been changed, I'd do that. It probably isn't the cause, but it can cause all kinds of blockages and whatnot if you still have the original after 100k. Plus it's cheap...I got mine for like $25 on www.thepartsbin.com
These are the instructions (http://www.stealth316.com/2-fuelfilter-upgrade.htm) for upgrading the fuel filter, but you can use them for swapping in a stock replacement.

It also wouldn't hurt to pressure test the intake (http://www.supercar-engineering.com/rubberducky/3S/Maint/TT/IntPresTest/index.html). If you have some massive air leak that for some reason the mechanic isn't seeing or hearing, that could cause idle and stalling issues. (if you don't have a vr4...ignore that one...however you can still look for broken or disconnected vacuum hoses and/or a crack in the intake manifold.)

Also the IAC (http://www.stealth316.com/2-isc-iac.htm) as mentioned above is notorious for dying and causing idling problems. They can usually be found on ebay for $50.

Those are just some random ideas. I'm leaning towards it being the ECU. If it is indeed automatic, and the ECU checks out fine, then let us know. At that point I would think it's a combination of both a tranny problem and one of the above mentioned things that would cause the idling/stalling problems.

grafixx3000gt
03-09-2007, 10:22 PM
thax for all the suggestions! although most of the things you guys mentioned,he said ,he tried. He was currently tring the ISC/IAC,but if that doesnt work he sounded a littel more opptomistic after hearing some of the things you had to say. i will defenitly keep you posted. please wish me luck, its been 2mo. with out her and i just dont feel whole any more! if any one thinks of any thing else let me know till then I.O.U. you guys are awsome!

Stealthee
03-09-2007, 11:57 PM
Definitely check the PTU. I just went thru a mini ordeal with my Talon. Yesterday morning the car wouldnt start. In 10* temps and by myself its hard to diagnose spark..... Fast forward to last night and my dad is in town for a few days so I get him to come out and help my check spark. He said I was getting spark but it looked very weak. After thinkng about it every once in a while lately the car "loads up" and acts like its trying to stall and I have to go WOT to get it go go anywhere then its fine again.

So I replaced the PTU and unfortunately the car wouldntstart but spark looked stronger. I played with my tune some more and the car is finally running again. If you can find someone near you with a known good PTU to try out go for that. Its an easy swap and if it doesnt cure the problem your not out any money from chasing gremlins.

grafixx3000gt
03-10-2007, 02:01 AM
Ptu was checked its getting a good spark.

Stealthee
03-10-2007, 06:44 AM
If all other resources have been exhausted its time to open the ECU.

grafixx3000gt
03-13-2007, 09:43 PM
is it suppose to take days to rule out 1 or 2 things?wtf!!!

Igovert500
03-14-2007, 08:59 AM
If he's busy..maybe. With directions on the internet, and the help of online forums, most of this stuff you could do yourself. Might wanna consider it.

grafixx3000gt
03-15-2007, 12:05 AM
the good news : i got her back:rofl:
the bad news: u were right, the mechanic was clueless:banghead: but the guy who fixxed it used it as a learning experment although im thank full i need a mechanic around pa who knows these cars and wont kill my pockets. :banghead: :banghead: :banghead:
the paper work was sloppy and their explainations were uneducated. from what i understand it was the fuel presure regulater. she runs good. and fast:grinyes: :grinyes: :grinyes: :grinyes: but while idoling it still surges:banghead: could it really be as simple as a loose screw over looked?:screwy: WHAT IS GOING ON?

Linebckr49
03-15-2007, 12:25 AM
good mechanic in PA? Igovert and Stealthee are both in PA. both very knowledgeable guys for our cars.

as for your idle surge, does it rise, fall, rise, and fall? sounds to me like a IAC/ISC problem.

Nesryn
03-15-2007, 11:50 AM
You should really check the ECU. If the capacitors are leaking, then that could be causing some of the problems you mention. The first gen's are notorious for having leaking capacitors and it's an easy and cheap fix. They're what's usually responsible for your problems when everything else has been ruled out...

grafixx3000gt
03-16-2007, 02:59 PM
Ok now I'm starting to get pissed. How the fuck could the car run good for 2 days then start doen the same shit again? I'm in the process of gathering info on the ecu caps,but wtf! Why did it run good for a while then just start doing it again? I'm ready 2 cry!

Nesryn
03-16-2007, 04:09 PM
Mine use to be finicky as well. It would run great some days with no probs at all and then out of the blue on other days it would surge at idle and then just randomly die if I didn't keep my foot on the gas. It was my ECU tho.

My friend's first gen Stealth TT had the same problem and replacing the capacitators fixed it. If you haven't, just check the ECU for the hell of it. You have nothing to lose, and it'll postpone you taking an ax to the hood of your car...

Stealthee
03-16-2007, 04:54 PM
Youre in Philly so Igo is MUCH closer than you. Philly is a good 5+ hour ride for me.

The ECU is easy to pull out and open up. Check out stealth316.com for instructions if you are unsure.

grafixx3000gt
03-17-2007, 04:51 PM
ok guys, i found a guy in my area that has a perfromance shop that deals alot wit 3000's. he told he could change my capasitors for a good price,BUT...he said it could be more if the ecu itself is damaged and has to be replaced. so how can i tell if hes telling me the truth and not just trying to get more money outta me? :banghead:

Nesryn
03-17-2007, 04:59 PM
Tell him to just do the capacitors and not worry about the ECU for now. If the problem doesn't go away after you change the caps, then maybe start worrying about the ECU.

AR Sweet
03-17-2007, 07:14 PM
Leaky caps can cause quite a few issues,but can ALSO be intermittent,which would explain the fact that it ran ok for a couple of days..

Igovert500
03-17-2007, 07:47 PM
Leaky caps are 90% of the time very easy to spot. If you look at the link I put int he first page of this thread. For removing the ecu and inspecting it. THere are pics of a normal board and of one with leaky caps. Honestly, if you can use a screwdriver...you can remove the ecu yourself and check it in under 15 minutes. He shouldn't charge you more than an hours worth of labor and like $5 for swapping the caps. For fixing the board if it's damaged, AVPRO will do it for $270ish...there is a section about them in the FAQ.

grafixx3000gt
04-04-2007, 09:52 PM
ok,sorry it took so long. so the moron who had my car finally listened to me and checked the ECU. he said there were no signs of leakege.so i said, lets just change the caps for shit and giggels any way. it took him 4 days to deside he didnt want to attempt it, for fear he would fry my board. so,he took the board to RADIO SHACK thinking they could do it.UNBELIEVABLE, i know!!! as soon as i get them changed ill let u guys know. this sucks! apparently this car is like a space ship to most mechanics. im thinking about just trading it in for a newer 3000. im at my wits end w/ this shit. if ur a mechanic, move to eastern Pa. we need you!!!

Stealthee
04-04-2007, 10:19 PM
Theres actually a few decent 3s mechanics in eastern PA. Hans at GZP. Greg, Monochrome, over on 3si, doesnt have a shop but he knows his shit. I beleive he may have just moved but hes still generally close. Theres a few more but there names are escaping me at this point.

Igovert500
04-05-2007, 08:54 AM
radioshack sells stuff, they dont do anything.

Look in the phone book for old tv or radio repair shops. Go in and talk to the people. Many times people lack the creativity to understand that you are using something different for your car, and they wont understand over the phone. But when they see a board and caps..they are like 'oh, I can do this for $20.'

The mechanic took the board to radioshack..he just proved his incompetance there...so why are you listening to him. Don't. It could still very easily be the ECU caps.

I will say it again, removing the ECU is easy. If you are honestly thinking about trading in this vr4 for another 3000gt. It would be less effort and time to pull the ecu yourself, then to put the car up on Autotrader. If you aren't willing to try pulling the ecu, I seriously suggest you think 2x about buying another 3000gt. These cars aren't cheap to own if you can't turn a screwdriver.

estolten1
04-15-2007, 09:10 PM
I know you said the exhaust wasn't blocked but I had the same thing happen to me on a couple of cars and it sounds like a clogged cat. At least look at the tailpipe for matalic particals. If There is, the cat's bad. It's worth a little look.

SarahMarie
04-17-2007, 09:02 PM
Ok now I'm starting to get pissed. How the fuck could the car run good for 2 days then start doen the same shit again? I'm in the process of gathering info on the ecu caps,but wtf! Why did it run good for a while then just start doing it again? I'm ready 2 cry!

I know how you feel, I'm having similar problems...Take it to the shop, works great for a little while, then, eh, not so much, then take it back, same thing... Now, it's not even driveable..:banghead: That's why i'm HOPING it's my ECU...:frown:
You RELLY should check it, heck, i'm 19, and a GIRL and i'm going to be taking mine out when the weather gets better. :tongue:

Add your comment to this topic!