3SGEL cranks and starts ok but stalls after a few seconds

[StuartM]

Hi does anyone have a service manual handy for a 1986 celica?
I would like to know what fault code # 24 is and code # 42 (my car starts then dies, i think its a temperature sensor/afm problem)

its no problem finding the 4A-G ecu fault codes but I think they are not quite the same as 3S-G

thanks in advane to anyone who knows!

[StuartM]

bump. found it out.
24 is no signal from THA (air temperature) sensor.

if anyone has any suggestions about my celica's problem they would be most welcome to post!

it will crank and start ok, but as soon as the ECU stops functioning in ASE (after-start-enrichment) mode it runs poorly and soon stalls.

[sergei]

Check if it s plugged, it should be on inlet manifold with yellow plug. There is posibility that the wire broke off (there are 2 wires going to it).
All this from memory, as I don't have anymore 3SGE but only 3SGTE so I can't confirm on the location. If you can't find THA, it is possible that is inside of AFM...

[StuartM]

yes its inside the AFM i have a 3S-GELU
the temp sensor is working correctly however
replaced my fuel filter and checked the fuel pressure. im betting its an AFM or ECU problem

[KinLoud]

Sounds like there might be a problem with your AFM wiring.
Check your check the condition of the AFM plug and socket, also check the EFI earths.
Sounds like the fuel pump isn't working correctly. The pump works when you turn the key to start. After you let go of the key the pump is kept going by a switch in the AFM that operates when the flap opens.
Find your diagnostic plug, try jumping the fuel pump connector to earth. This will make the pump go all the time when the ignition is on. If your engine then runs normally this probably confirms a problem with the AFM or the AFM wiring.
DO NOT RELY ON THIS TEMPORARY FIX!!! Fix it properly!
If you crash and the engine stalls the pump will keep pumping instead of stopping when the engine stops. If you break a fuel line the pump will squirt lots of lovely fuel to make the fire burn brighter and cause you lots of stress!!

Ken
Ham
021 408 863

[Rob]

Had a simillar problem, took it to a sparky and they took about 3 months to rewire the fuel pump straight to the air low meter instead of through the really, so check your power to your pump.

[sergei]

Had a simillar problem, took it to a sparky and they took about 3 months to rewire the fuel pump straight to the air low meter instead of through the really, so check your power to your pump.

It does not take 3 month to rewire fuel pump, also if you connect the AFM contacts directly to fuel pump, there possibility of burning off the contacts.
Why they did not replace fuel pump relay or wiring whichever was faulty in first place? Ohh well there are plenty auto sparkies that don't know what they are doing (or don't want to do it properly because it does not pay).

if car stalls on idle it pays to check if you don't have any vacuum/air leaks.. you can check if the sensor is faulty using multimeter, it should be arround couple of kiloohms at room temperature (and decrease with increasing the temperature)...

[sergei]

3SGE airflow meter should have following pins in order (looking at AFM from plug side, left to right):
Fc, E1, E2, Vb, Vc, Vs, THA
measure resistance (with plug disconnected) between THA and E2, resistance should be in following range:
-20'C -> 10-20kOhm
0'C -> 4-7kOhm
20'C -> 2-3kOhm
40'C -> 0.9 - 1.3kOhm
60'C -> 0.4 - 0.7kOhm

Resistance between Fc and E2 should be infinite if engine stopped.
If you push AFM flap with finger while measuring resistance between Fc and E2 it should jump to 0 as soon as the flap moved a few millimeters.

[matt dunn]

Umm,

1986 3SGE celica should not have an AFM, it should have a map unless it's a turbo (3SGTE) shouldn't it??

[Boosted_162]

Nah, the ST162's did have an AFM. If i remember correctly, its the ST182 that doesnt have one but the ST185 does.