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420A Car Dies after idling 5-10mins with no codes.

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Slow_Rs

Proven Member
50
2
Oct 23, 2020
glasgow, Kentucky
currently trying to fix my car after it previously died on me two times randomly, no sputtering or anything, just boom, dead, i’m at a loss of ideas to try, the only thing i could think to check is the crankshaft sensor or ECU, i’ve replaced the crank sensor about a month or two ago and it still looks brand new, i’ve also replaced the camshaft sensor and swapped out an ignition coil for a different one that works for sure and the car still dies after idling for 5-10mins, no warning, just does, and absolutely no codes pop up, when the car used to do it it had a p1391 code but now it doesn’t show anything at all.
Any help is greatly appreciated!
 
when it does can you start it back up right away?
if you can't, try starting it again with your foot barely on the pedal. you just want enough pressure so the throttle plate is slightly open.
If it starts then, chances are its the idle air control motor.
 
when it does can you start it back up right away?
if you can't, try starting it again with your foot barely on the pedal. you just want enough pressure so the throttle plate is slightly open.
If it starts then, chances are its the idle air control motor.
it doesn’t not start up right away, it takes a good minute for it to start up again after it does it, i’ll try that though
 
when it does can you start it back up right away?
if you can't, try starting it again with your foot barely on the pedal. you just want enough pressure so the throttle plate is slightly open.
If it starts then, chances are its the idle air control motor.
just tried that and the car just kept wanting to turn over and not start
 
you need to check the ASD and fuel pump relays
if you dont' know where they are, it would be A-68 and A-69 in this diagram.
the ASD relay is the one with the gray plug
the fuel pump has the black plug
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If you know how to check them with a meter you can do that. Otherwise you need a 2nd person.
So whenever it dies and isn't restarting, one person put their finger ontop the relay, the other tries to start it. If its operating correctly you will feel it click when it activates. try the ASD relay first, if that is okay try the fuel pump relay.
Some times when they go bad, they will work for a litttle while but then heat up to the point they stop working and won't work again until they cool down.
 
you need to check the ASD and fuel pump relays
if you dont' know where they are, it would be A-68 and A-69 in this diagram.
the ASD relay is the one with the gray plug
the fuel pump has the black plug
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If you know how to check them with a meter you can do that. Otherwise you need a 2nd person.
So whenever it dies and isn't restarting, one person put their finger ontop the relay, the other tries to start it. If its operating correctly you will feel it click when it activates. try the ASD relay first, if that is okay try the fuel pump relay.
Some times when they go bad, they will work for a litttle while but then heat up to the point they stop working and won't work again until they cool down.
so they should constantly click? or just click once when you try and start the car
 
they click when they activate, just once and shouldn't click again until they deactivate. So when the car isn't starting, if the relay is bad, it either won't click at all or it will click multiple times. so if you feel it click 2x the 1st was it activating and 2nd time it was deactivating.
If the relay doesn't click at all it doesn't me the relay has to be bad. But i will know what to check next
 
they click when they activate, just once and shouldn't click again until they deactivate. So when the car isn't starting, if the relay is bad, it either won't click at all or it will click multiple times. so if you feel it click 2x the 1st was it activating and 2nd time it was deactivating.
If the relay doesn't click at all it doesn't me the relay has to be bad. But i will know what to check next
checked relays and they’re fine, they clicked and i even tested with a multimeter and they’re reading fine
 
this is from the manual. its not the whole procedure, i left out the stuff you already checked.
I also put a link, at the bottom, to download a section on checking the ignition system including cam and crank sensors. Its from the neon manual so just ignore the stuff about the SOHC engine and anything that refers to a fuse or fusible link. All the other stuff is the same. It better than what is available in the mitsubishi manual.

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this is from the manual. its not the whole procedure, i left out the stuff you already checked.
I also put a link, at the bottom, to download a section on checking the ignition system including cam and crank sensors. Its from the neon manual so just ignore the stuff about the SOHC engine and anything that refers to a fuse or fusible link. All the other stuff is the same. It better than what is available in the mitsubishi manual.

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what about a shot o ring on the crankshaft sensor that leaks a little, would that cause the car to just die all of a sudden, i was reading the manual and everything mentioned in it i’ve done already expect the relays which is what i tested today.
 
a leaky oring shouldn't matter. Have you listened to make sure the fuel pump runs when the car isn't starting?
It only kicks on for 1 second when the key is first turned on and then i won't run again until the engine starts cranking.
If you have a stock fuel pump, they aren't very loud. you probably need to remove the gas cap and put their ear by it to hear the pump.

the ASD relay supplies battery voltage to the fuel injectors, electronic ignition coil and the heating elements in the oxygen sensors.
If the PCM does not receive crankshaft and camshaft position sensor signals when the ignition switch is in the Run position, it will de-energize the ASD relay.




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a leaky oring shouldn't matter. Have you listened to make sure the fuel pump runs when the car isn't starting?
It only kicks on for 1 second when the key is first turned on and then i won't run again until the engine starts cranking.
If you have a stock fuel pump, they aren't very loud. you probably need to remove the gas cap and put their ear by it to hear the pump.

the ASD relay supplies battery voltage to the fuel injectors, electronic ignition coil and the heating elements in the oxygen sensors.
If the PCM does not receive crankshaft and camshaft position sensor signals when the ignition switch is in the Run position, it will de-energize the ASD relay.




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yeah the fuel pump kicks on, it has a new fuel filter, and the injectors fire correctly
 
i know this is a little late since you already bought cam/crank sensors, but alot of the parts store cam and crank sensors are trash with autozone being the worst.
i fixed 420a sebring that was having issues. i don't remember what the exact issue was but it either wouldn't start or it may have been the same issue your having. and of course the owner said the cam sensor was brand new. anytime someone says that i'll grab one of the old Mopar sensors i have laying around and take it with me when icheck out the car. As soon as the hood was popped i swapped in the old Mopar sensor and no more problem.
It goes like that 75% of the time.
my point is, it may just be a shitty sensor even if its new. Usually a used OEM sensor from the junkyard is better than a new autozone sensor.

If it was the crank sensor it should kill the ASD relay.
 
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i know this is a little late since you already bought cam/crank sensors, but alot of the parts store cam and crank sensors are trash with autozone being the worst.
i fixed 420a sebring that was having issues. i don't remember what the exact issue was but it either wouldn't start or it may have been the same issue your having. and of course the owner said the cam sensor was brand new. anytime someone says that i'll grab one of the old Mopar sensors i have laying around and take it with me when icheck out the car. As soon as the hood was popped i swapped in the old Mopar sensor and no more problem.
It goes like that 75% of the time.
my point is, it may just be a shitty sensor even if its new. Usually a used OEM sensor from the junkyard is better than a new autozone sensor.
i’ll look into actual good ones to get and i’ll update if it fixes or not, i appreciate your time!
 
here is a good writeup on checking the cam sensor
 
i know this is a little late since you already bought cam/crank sensors, but alot of the parts store cam and crank sensors are trash with autozone being the worst.
i fixed 420a sebring that was having issues. i don't remember what the exact issue was but it either wouldn't start or it may have been the same issue your having. and of course the owner said the cam sensor was brand new. anytime someone says that i'll grab one of the old Mopar sensors i have laying around and take it with me when icheck out the car. As soon as the hood was popped i swapped in the old Mopar sensor and no more problem.
It goes like that 75% of the time.
my point is, it may just be a shitty sensor even if its new. Usually a used OEM sensor from the junkyard is better than a new autozone sensor.

If it was the crank sensor it should kill the ASD relay.
i just tested the cam sensor and everything was reading like it should
 
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