Something Electrical?

[nasty87supra]

my scenario is today i went to pick my wife up from work and leaving the house to get into the car the engine turns right over when i get to my wife's job and i waited for her for about 15mins. obviously i turned the car off. now when my wife and i are ready to get back in the supra the engine has a hard time turning over, example the starter keeps cranking and you can hear that the engine wants to turn over but it's just having a hard time. so after about 5-10 times of turning the key the engine kicks on but shuts right off, so i turn the key once more and when it comes on i gently step on the accelerator pedal and rev the motor and it stays on but is idling at 1500rpm without my foot on the accelerator. once it's on it drives smooth and if it shuts off again the motor turns right over without a problem but i've noticed my supra has this problem during short term driving like from the babysitter to the grocery store and to the cleaners. you know driving where the vehicle is being turned on and off constantly. i've checked all the electrical lines on the top and sides of the engine and even electrical lines under the car and everything seems to be "A" okay but i don't want to put this problem ahead of me. is there something i may have missed? has this ever happend to any of you guys? oh yeah this problem happens during cold or hot new york city weather if the weather plays a role in this problem.

[TcmaBoy]

Um...when you say "won't turn over" do you mean the starter engages, but the engine dose not fire, or do you mean the starter won't work and/or is slugish. What is the temp gauge reading when you have a hard time? Is this a problem when the engine is hot or cold? If it is a hot problem dose it occour at normal operating tempature (180 to 210 deg) or hotter? Is this a turbo or NA car? I take it from your name that it is an 87. When you checked the wires did you test them with a multimeter or just look at them?

[ahmedootie]

i do not know what tha part i am talking about is called, but if u follow tha 3000 pipe (turbo cars) to tha throttle body, theres a little cylinder coming out perpendicular to the 3000 pipe, u can put a flat head screw driver, and turn it both ways, my car did the same thing, and i turned it a half a turn clockwise, i believe this adjusts tha idle, and it worked perfectly after that... i dunno wut ur specific problem is, but that could be something u might wanna look at.
hope that helps

[bgrieger]

Wrong advice on the adjusters. There is the dashpot, and the throttle close position. Leave them well alone. Your problem sounds like classic fuel. Either heat soak, or a faulty cold start injector. I'm leaning to heat soak, as it is pretty common. I get it as well, and have yet to find a single positive cure for it, aside form goosing the gas while cranking (with a risk of flooding it), continued cranking and rev it up as soon as it starts (the erratic revs go away quicker...more liquid fuel), or finally waiting it out.

[Jeeves]

This condition is well known as heat soak.

[nasty87supra]

so mister jeeves what do you suggest i check out or fix? is bgrieger right? there is no cure for this except to just mash the gas while starting or give it a short wait period between starts? and jeeves may you explain heatsoak to me please. and does heatsoak only happen to vehicles with force induction?

[Jeeves]

More cooling will help, but this is a problem on all cars that run hot. The supra is just a very good example of it. In this case, the fact that it has an intercooler and the way the intake path runs all help it occur.

Explanation (Think of it like this):
Your car goes from cold, to hot quickly. Everything is rip roarin', tearin' it up.

Then it's suddenly off, however, you've got a whollle lot of thermal energy pent up under that hood. Pipes get hot, left over fuel turns to gas, parts that only run well when cool, or cooled get hot, oil cooks in bearings, hot coolant stays hot in the middle of the block or in the throttle body, etc.

Now, you try to start it up. Everything is hot. The intercooler which is supposed to cool down the intake charge has gotten heat soaked, and doesn't do any good. The throttle body is sitting over a hot engine, so it's only suppling hot air so the air/fuel ratios are nasty, etc. Nothing is at an optimum range, everything is at extremes. While my explainations are rather poor, and the details are lacking, I think you can get the picture.

Eventually, the car gets all it's cooling systems in order, you get fresh air moving and everything goes back to normal.

How to help it:
Invest in a turbo timer. Personally, I should have made it my first mod. It's that important.
You can walk away, and it'll time itself down, after XXX period of time it'll turn itself off. If you drop the handbrake or try to drive it, the car will turn off. And since you've taken the keys with you, no one is stealing your car this way.

Any way you can increase the cooling system of the car will help, however even in my decently modded car, Heatsoak is not something I can escape.

What you can do in the meantime:
Not much really. Make sure your shroud, stock fan clutch, and under carriage covers are intact and inplace, let the car idle for 30-45seconds before just turning it off (listen to part of a song or something), etc.

When you start it up, it may still be there. All you can do is pretty much what you did, start 'er up, crank and give it gas. When it catches keep on the gas a bit, and just start driving. It'll work itself out.

[nasty87supra]

thanks jeeves it's not that i'm cheap but i know about the turbo timer situation and it is something that should be invested in but this mk3 is my 1st vehicle with forced induction and my d.s.m. friends have warned me about turbocharged cars and especially in hot weather vehicles like ours need to be checked and engine fluid levels should always be topped off. but since i've never invested in a turbo timer is there a difference in having a turbo timer and waiting 5 minutes at idle with no movement in a parking spot? because that's what i do. but thank you again jeeves your experience gives me persistance

[albertmdh]

yeah, 5 min is more than enough time, i ussually just listen to a song, like jeeves said, though i havn't had any heat soak problems.... yet.

[Jeeves]

Damnit, where'd my post go?! Gah!

/retypes

Yes, that is the exact same thing a Turbo Timer will do, However... Do we always sit in our cars? No. We get busy, and rushing and don't have the ability to sit with them all the time. Turbo timers do it everytime though, and that's what is needed. The average turbo time is usually between 30 -> 90 Seconds. 5 minutes is really overkill.

Personally, buy a turbo timer. They're worth every penny.