marshallc

picked up a 96 black/black sc300 na-t as a toy/ project car and am having some issues with it, id perfer not to start the build i had planned this early as i stilll have a month or two to enjoy it, but my issues im having with it have me stumped.


its a 300 with a tt supra hg, arp studs, rx7 550's, pump, map ecu, xs power kit.


car was running great, i took off from a light, shifted to 2nd, and the car fell on its face, went from that silky smoooth toyota i6 sound to a subaru like burble. limped it 10 miles home, no pop, no clank, no ticking, if id try to give it more than 15% throttle it would die out, and would not hold idle to save its soul.


at idle it dumps white smoke, but it does not smell like coolant, it reaks of raw fuel.

i checked the ic piping/ vac lines and everything is solid, and i pulled the number 1 and 5 plug as there the easiest to get too, and everything looks fine, just rich, but rich is safe


anyone have any trouble shooting ideas?

i read a thread about similar symptoms and it was the ecu, but the thread was in regards to an obd1 car not an obd2 and i dont know if the ecu issues carried over.



thanks in advanced

Ali SC3

iTrader: (10)

check the vac line that goes to the map ecu. it uses this for boost reference.
you can also try resetting the stock ecu, it can help every once in a while.

marshallc

i tried resetting the ecu, also unplugged the o2 sensors thinking maybe that could have something to do with it, made no difference.

good2go

iTrader: (6)

This sounds just like when you lose a map sensor signal. Like Ali said, definitely check the vacuum tube going to the mapecu ok, then check that the mapecu is getting power. Could also be a bad connection where the mapecu was patched into the ecu harness.

Ali SC3

iTrader: (10)

yeah you didn't say anything about checking the line for the map sensor. on the map ecu 1 it is built into the unit and its just a slip on connection which is just terrible to be honest.

Also have you ever checked your cap and rotor on the distributor?
If it sounds like its running on less than 6 cylinders and has a "rythym" to it, your cap/rotor contacts could be worn down. mine went out in a parking lot and i was running on 4 cylinders till i figured it out. this one is an easy fix about $15 and a screwdriver will get the job done.

marshallc

where do i locate this map sensor? haha im gunna mess with this thing after work, so anything you can suggest to mess with would be great.

Ali SC3

iTrader: (10)

peel back the pasenger side carpet under the glovebox. there you will find ur stock ecu and the map ecu. make sure the vac line going to the map ecu is still connected tightly, it should run all the way to the intake manifold, also make sure its not kinked or anything.

marshallc

is it possible a loose battery connection could have tripped the map ecu out and it reset the tables to default/ zeroed it out?

attzor

iTrader: (1)

A loose battery connection will cause the car to have no idle unless you instantly give it throttle to keep the alternator going, but I don't think it will reset map ecu, never did on my old car and I had the battery in and out all the time.

marshallc

daum. all vac lines/ connections are solid and it still runs like booty. possible i did some internal damage?

it sounds like the injector driver or the ecu went bad as it just dumps fuel and smokes white like mad out the exhaust but its fuel nor coolant.