Help I Dont Know Whats Wrong - Toyota Nation Forum : Toyota Car and Truck Forums

madmann29 · 07-27-2005, 03:05 PM

Hi, i have an 87 supra turbo, and when the car idles it goes from like 400RPM to like 600RPM, and sometimes even goes so low that it just stalls. and also when i drive it when shifting it jerks back and forth, and black smoke comes out of the back, and i dont know whats wrong. I'm hoping it just needs a tune-up but i just wanted to get some other opinions of what it could be, so help would be appreciated.

Thanks

damone · 07-28-2005, 01:12 AM

check the ISC motor.. as soon as the engine is shut off, you should hear a faint clicking noise coming from the ISC motor for a second or two.. you might need someone to shut the car off for you.. then pull it out and clean it real well with throttlebody cleaner

also check around for vacuum leaks.. I've built an effective vacuum leak finder out of a 4" PVC endcap and a tire valvestem.. finds the smallest vacuum leaks..

madmann29 · 07-29-2005, 11:23 AM

ok thanks i'll check for vacuum leaks, but what is the ISC motor?

damone · 07-29-2005, 05:20 PM

The ISC (idle speed control) is the motor that lets air bypass the throttlebody to maintain engine idle.. But sometimes it gets gunked up and cant open and close properly..

Its the black thing bolted to the intake manifold right beside the throttlebody.. It'l have a wire connector on it with 6 wires.. Also check the condition of those wires, and the rest of the wiring under the hood.. the wiring on the CPS (cam position sensor) is notorious for crumbling at the harness, which will also cause irratic idle..

madmann29 · 08-01-2005, 09:51 AM

ok thanks i'll check that

heavyearly87t · 08-09-2005, 03:08 PM

Did you ever get thiss sorted? Your AFM could be unpluged or even quit. Just behind the air intake on the AFM(Silver) is a black box. Be sure it is pluged into the wiring.

Jeeves · 08-09-2005, 03:59 PM

An unplugged AFM would have serious issues other than his sypmtoms, namely a rev-limiter.

madmann29 · 08-10-2005, 10:07 PM

Hey, well right now the car is in the shop, and the mechanic said that my check engine light doesn't work, so he needs to hook that back up, then he is going to diagnose the problem. Thanks for all your help though!

lord lucan · 08-11-2005, 12:19 PM

hey Jeeves please dont take this the wrong way -but-it may be the english/american differences in the way we comunicate but you always seem to come across as having issues with everything,i may be talking out of turn and i appologise if i am but you kind of seem a little condescending to peoples ideas ands answers if they dont agree or have different views on things to you...im not saying you dont know shit as you obviously know toyotas pretty well but u seem a bit sour to people and a bit stood on a brick.there are ways to get your view point across without blasting people out the water all the time...just my peneth,what do i know ive only been a member for a week or so,was just hoping this place was a bit diff to all the others but im not sure it is....you know mechanics and cars are a constant learning curve and you never know it all....! any input at all can be helpfull even if its wrong.....be interesting to see how you take this answer...spect i will get slated now but i dont really care coz i have my toys and a life apart from a forum soooooo......just stating constuctive criticism.....just dont want want people being scared to input in the fear you will pearl harbour them.

Jeeves · 08-11-2005, 04:46 PM

1) It's a forum. I don't know you, you don't know me, that's the way it's supposed to work. I've got my views and you've got yours. I'm appreciative of the posters who come on and talk and exchange information and can type clearly and suscinctly (RepinS, bgrieger, etc.) but if you're a noob that can't find the shift key and you mistake the period key for the space bar then you can expect to be on the receiving end my dislike. I don't try and talk about the innter workings of a turbo to a real life 5 year old, so why would I discuss that with someone who types like that 5 year old talks?

2) I am a hardass, that's pretty much all there is to it. I know my shit about Supras and cars in general, yes, but I will never say I know everything. My stance is that I state the facts I know, if they're wrong prove it, you'll teach me something. If people just don't like what I have to say, it pretty much sucks to be them. I like to think that when it's not a flat out opinion, I'm usually 90% right about anything.

3) I am avidly against rice and worthless, weight adding modifications. Bigger airdam for better airflow across an aftermarket Intercooler? All the power to you. New front airdam because it looks cool, has pointy corners and looks shiny... expect me to hate it.

4) On top of that, I hate people who come in and ask questions without searching or doing any research for themselves or just don't use common sense (Mk4 Supras for $3,000 for instance). If they found this forum, they can use the search feature. I am not a fan of doing people's homework for them. If information is tougher to find, or jumbled, I'll make a structured, organized post (See: VIN Decoding & Engine Decoding) and bring it all together.

5) I'm not looking for people to be fearful of me, that's not the point. The point is clear, concise communication.

6) I've heard this before. Always from the people I ride, and yes, you're one of them. You're not slated now, you were slated previously. It doesn't take that much effort to type well.

Long story short, it's not differences in culture. There may be some of that, but really, I'm just a Hardass.

lord lucan · 08-12-2005, 03:36 AM

fair enough.

lord lucan · 08-12-2005, 03:41 AM

what is a "hardass" it doesnt translate too well in UK terms. (serious request,im not trying to be funny)

lord lucan · 08-13-2005, 08:53 AM

hell yeah !!!! just checked out your post on VIN numbers,god thats well written and neat.......think i might just have to print it off and have a moment with myself in quiet.

were you ever bullied at school?

***Tercel GTS*** · 08-13-2005, 10:24 AM

Quote:

Originally Posted by lord lucan

what is a "hardass" it doesnt translate too well in UK terms. (serious request,im not trying to be funny)

A hardass is a person that insists on doing things in a proper fashion.
Catholic school teachers are excellent examples.
A strict judge would be another good example.

I have a lot of respect for Jeeves! His posts are always very informative and to the point. I can't stand reading posts that pose a querstion and take 4 paragraphs to ask the one question and still don't give enough information to diagnose the problem. Also, TyPiNg LiKe ThIs WiLl MaKe Me IgNoRe YoUr QuEsTiOn EvEn If I kNoW tHe AnSwEr. Lastly, THIS IS ANNOYING ALSO.

Jeeves =

lord lucan · 08-15-2005, 07:42 AM

THanx wish I COULd be HARDass tOO.