soardrft

iTrader: (8)

ok i assume its just time for my swap, but maybe i can hold out til x-mas. the situation is this. my cars keeps shutting off. it won't keep idle unless the ac is on and it dies out shortly after. when i re-start the car i smell gas which leads me to believe its a fuel problem and my motor is just fine. i am close to 100k and did minor work such as: new clutch flywheel, and belt change. However this was happening before those changes. can anyone assist me with this? so just to make sure i am clear these are the problems.
it won't keep idle
will shut off if at a complete stop or placed in neutral
smells like gas when restarting
variable jerks when driving in every gear

A true POS right now Please help i have 3 weeks before the shop is ready for my swap, and i have a couple of dates before then.

Thanx in advance

vipsoarer

sounds like you are running rich since you smell gas and the car jerks. i would pull the intake manifold (pain in the *** i know) and check your spark plugs to see if they are fouled out along with if you have leaky injectors. good luck and keep us posted.

VJ RC51

maf, ecu, idle motor....

From my experence with 2 SC's... whenever something acts wierd, its the ECU. I tend to replace one every few months, solves any issue. They suck. I know a buddy with a 95 supraTT, he's been thru almost 5 this year.

TeamDX

Then you and your friends have 0 clue how to diagnose issues. ECUs dont go bad out of nowhere.

soardrft -

Id suspect plugs as well. Take off the throttle body and put fresh plugs in gapped properly, and make sure all plugs are torqued exactly the same from top to bottom. Then give it a shot.

VJ RC51

My first bad ecu = car ran rich when it was cold, like so rich it would misfire and spit fuel out the exhaust and had dead spots in the rpm range. 2nd bad ecu = overdrive didnt work, 3rd bad ecu = AC didnt work, 4th bad ECU = car didnt start at all.

vipsoarer

i agree you should not be going through ecu's so fast. i suspect some sort of ignition problem with the first ecu. i would try many other routes before swapping ecu's. most ecu's also show 00 codes or 1's when defective

Koma

iTrader: (3)

VJ if you were having ECU issues you did you try resetting first? I would've gone that route first and if the ECUs really were shot than you have bad luck dude. I'm guessing you did reset but just a suggestion for the person runninng rich right now.

I've noticed an issue with my SC400 if you pump the engine (blip the throttle while in gear and let it jump foward and let the gas go abruptly) the engine won't keep a nice idle. It also may cut out if you're in a full stop. I'm guessing the reason for this is that since your pumping the engine with gas and not really burning it all than your essentially making the engine run rich. Try running fuel cleaner into your system to clear out any excess buildup from such instances. It should clear up if it is this issue. I stopped blipping my engine like that from now on.

BLK13X

Sounds like your fuel pump or the fuel pump ECU is on it's way out.

VJ RC51

Yeah i diagnosed everything on the first one running rich, plugs, wires, sensors, pump, spent like $500 in parts for nothing. ECU never thru a code and it was defective.

0l33l

iTrader: (3)

I noticed the same exact thing on my SC300.

nasc300

If it's the ecu, then it's just a capacitor that has gone bad. I have had the same problems with two Supra's and both had the same leaking capacitor. I know little about electronics but once I figured out that the problem was the ecu I decided to open it up and look around. and after careful inspection I saw the leaking thingy. I turned out to be a leaking capacitor wich cost me about $0.50 to replace. I repaced it myself. Both have more than a 2 years since the repairs and are still fine.

Mikethe1st

How did you to diagnose a leaky capacitor with no electronic knowledge? Pretty impressive. If you havent run the ecu diagnostic yet you should. Engines depend on Fuel/ spark/ and air, as you know, people always throw out a ton of suggestion but it could be about 20 different possibilities. With the a/c on it raises the idle which probably is keeping the car alive for a few minutes.
Here's a small list of what could cause this problem just off the top of my head:
Bad FPR, bad fuel pump, clogged fuel filter, leaky injectors, vacuum leaks, bad maf, extremely clogged air filter element, electrical faults/shorts, bad ecu, bad spark, bad distributor /timing wayyyy off.
The best start to finding the problem is to check ecu codes and check all the spark plugs which will all probably be black and sooty from running rich. I thought the shop was almost ready to drop in your 1jz? You wanna be on Shockdrifting??

0l33l

iTrader: (3)

Its the capacitor that doesn't look like the rest. A quick search on google will show what a bad cap looks like.

JspecSC3

iTrader: (4)

I had the similar problem. After driving off after a complete stop my car would just shut off so I would have to pull over and restart it. It was quite embarrasing. The idle was kind of weak. As if it were ready to shut off at the stop light or something. I took it to a couple shops and they both told me the same thing. They said it was my fuel pump that was about to go out. Try checking your fuel pump. Maybe that could be it.

nasc300

Like I said by looking at the circuit board. no testing is needed.

After I was certain that the ECU was bad (I tested a known good one on the car) and knowing that fist gen DSM's all suffered from leaky capacitors I was hoping to get lucky. I decided to open the ECU just to look around for a "burnt or leaky stuff". Just look you may see the problem.
BTW I only opened the ECU because I was certain it was bad and had nothing to loose