car wont stay running!!!!!! HELP!!!!!!!!!

[pandae86hid]

well i just put in a new motor and turbo(4agte) in my 86 and now the engine wont stay running. it starts up but immediately cuts off. I am using the greddy e-manage ultimate for my tunning which may have something to do with it but i dont know. otherwise, any suggestions?

[pandae86hid]

my car has AFM by the way and i need major help!!!! any help is greatly appreciated!!!!

[jondee86]

The classic cause is that there is no power to your injectors. The
car fires up on the cold start injector (only works during cranking).
Once you let off the key, it just uses up whatever fuel is in the
manifold and dies.

Check that you have 12 volts available at the injectors whenever
the ignition is "ON".

Cheers... jondee86

[Mux213]

Actually I am not sure if this applies to you since you're running on an aftermarket ECU but I have a suspicion the car won't spark if it senses something wrong with the coolant level.

I've had some mysterious non starting problems intermittently. My radiator is leaky and it always coincided with my coolant level dropping to low.

I replaced my radiator and after filling her back up there was still alot of air in the system and the car would not turn over, it just kept dumping in fuel and not sparking. Once however it had pumped the air out, it started right up no problem.

[jondee86]

Quote:I have a suspicion the car won't spark if it senses something
wrong with the coolant level.

Weird, but unlikely to be related. There is no sensor for low coolant.
I have started and run (for a minute or so) my engine when it has
been totally dry Air in the cooling system does seem to be
a contributor to erratic (loping) idling, although I have yet to figure
out why this happens.

Cheers... jondee86

[Bean]

have you checked all grounds... when I replaced my HG I forgot the ground for the intake manifold and the engine died after a couple of turns... don't know if this applies to your swap aswell though

[Mux213]

jondee86 Wrote:

Quote:I have a suspicion the car won't spark if it senses something
wrong with the coolant level.

Weird, but unlikely to be related. There is no sensor for low coolant.
I have started and run (for a minute or so) my engine when it has
been totally dry Air in the cooling system does seem to be
a contributor to erratic (loping) idling, although I have yet to figure
out why this happens.

Cheers... jondee86

Hey Jondee,

I don't think its coolent level itself, I think that when the coolent level drops so that there is no coolent near the temparature sensor, the tempature sensor gives irratic readings and the ECU gets confused. In my case I think its actually the engine getting flooded because of this and the flooding causing the starting problems.

The idling you mention is what i've experienced before aswell.

Running a 4AG at idle without coolent, daring! Actually I think these engines can take alot. the oil cooler takes the blunt of the cooling in that situation and toyota engines are notoriously relyable. My sister had a faulty radiator in her Starlet couple of years ago, her fix was just to wait until all the coolent had evaporated, when it stopped giving off steam she figured the problem fixed and drove the car home.
Offcourse this meant there wasn't a drop of coolent in the car

Engine survived this treatment a few times until the radiator was finally replaced.

[pandae86hid]

well I have the stock coolant sensor removed and unplugged, and in place is a autometer sensor hooked to the guage....... could that have something to do with it? i was reading that manual on the homepage and it said under the no start condition to check the coolant sensor which i thought was weird but who knows. Thanks in advance for all the help anyone will be providing!!!!!

[pandae86hid]

Quote:Mux213 Posted: Fri Mar 21, 2008 9:28 am Post subject:

--------------------------------------------------------------------------------

Actually I am not sure if this applies to you since you're running on an aftermarket ECU but I have a suspicion the car won't spark if it senses something wrong with the coolant level.

I've had some mysterious non starting problems intermittently. My radiator is leaky and it always coincided with my coolant level dropping to low.

I replaced my radiator and after filling her back up there was still alot of air in the system and the car would not turn over, it just kept dumping in fuel and not sparking. Once however it had pumped the air out, it started right up no problem.

its not a full replacement ecu, just a piggy back system that adds more fuel and stuff. i dont think it would cause a no start like this but i could be wrong

[jondee86]

With standard AE86 RWD water lines, the sensor for the coolant
temperature [color=red:10f6d6c5ca]gauge[/color:10f6d6c5ca] is at the front by the water pump. The sensor
for the [color=red:10f6d6c5ca]ECU[/color:10f6d6c5ca] coolant temperature input is at the back, next to the
cold start injector switch.

Which sensor have you unplugged ??

The gauge sensor is not part of the engine management, but the ECU
sensor adds more fuel at low temperatures. I don't know what effect it
would have if it was unplugged, although I doubt that it prevent the
engine from running.

Cheers... jondee86