97 NEON DIES. Confused. Need help.

[NFarran]

This is a very confusing problem, My neon dies when the motor is under stress, idles fine. After it shuts down there are no lights on the dash but 1 the oil light. Will not start agian unless I wiggle wires around under the hood this may not have anything to do with it but sure is a confusing problem. I pealed off all the tape and plastic looked over the wires and found nothing. All the fuses and relays are good and replaced sence this started well the relays anyway. Now that this has become a problem with driving I look back and remember a few times where the car seemed to lose power for a few sec's then come back.

[palindromelol]

Well well NFarran,

Sounds like what I endured which began my love/hate affair and intimate dismantling of my entire Neon. Do you have any engine codes? Do you know how to get them. Is your engine service light blown? It is going to be 20 questions I'm affraid. There are lots of folks here that know the ropes so listen and do.

[das2123]

The intermittent power loss you are describing sounds like a battery problem/connection. Make sure you're battery terminals are real clean and shiny, I mean real clean and shiny. Also make sure they are real tight and are making a good connection. The neons are real sensitive to corrosion and have to be tight. After that you may want to look at the actual wires, see this post. This should get you started.

[NFarran]

Error codes

12 - Direct battery input to PCM was disconnected within the last 50 key-on cycles

42 - Fuel pump relay control ckt, Auto shutdown relay control ckt, No ASD relay output voltage at PCM, Fuel level sending unit volts out of range

55 - end of codes

Something very interesting happend to day the car acted like it had very low battery power for a few min's then come back to full power so I cleaned and checked the cables as das2123 said, but car still dies under stress.

And yes all the lights on the dash are in full working order.

[palindromelol]

Ignor 12. It is always there.
Auto shutdown is interesting. Activates on either control circuit either Fuel Pump or Auto shut down Relay in the PDC. An open or shorted condition on either the asd control circuit. [CONTROL CIRCUIT]

The relays are both in the PDC just behind the battery in the PDC the relays are side by side.

Fuel pump relay is fed by a brown wire.
Auto Shutdown relay is ground by PCM by DK Blue/ yellow. It is FED by red/white at PCM sourced by fuse 21.

The Fuel Pump control is fuse 10. Several devices are on the circuit. EGR Solenoid, Vap Cannister leak detect, duty cycle evap purge, Torque converter clutch solenoid.

Fuel pump supply.....fuse 21 20A.....also supplies OBD2 and autoshutdown control.

AUTOSHUTDOWN ....same feed...

Auto shutdown relay will cut fuel injectors and noise suppressor... O2 Sensors... and ignition coil pack.... I think generator field coil.

I think this is determinable. Idles fine right?

[NFarran]

I beleave this car was sold to me with a selfdestruct. I've checked everything I could come up with, and every thing I was told here and from a dealer. I am begining to think somthing is making the autoshutoff fire, shuting down the car. But the book I got on the car doesn't talk about what would make the autoshutoff kill it. sence I got this car I have taking very good care of it. Under the hood looks like it just come off the showroom floor. I'm at a lost and really need help. I will allways do my own work on my vehicles, To pay someone to do it for me is just lazyness. So any other ideas that you have Please post no mater how stupid you think it may be, after all this car is acting very stupid.

[palindromelol]

When you say "dies under stress" please explain more about this stressful condition. What is the speed? what are you doing with your feet? Did you hear the transmission shift (auto or manual)?

[NFarran]

The car is a 97 SOHC 5 Speed manual.

Once I get it started It idles perfect and I can rev the engine as high as I want to. I can drive it around for alittle bit, But seems if I try to get it up to speed the car just dies. the lights don't lose any power, and nothing seems to get dim like the electic is being interupted. Also once I get it started the code 42 is no longer there until the car dies again.

[palindromelol]

Questions. OK Can you make it die while stationary while doing a mild brake stand. My intent here is to isolate a torque realted problem from a speed related problem from a power related problem from a random problem. Is there water/ weather involved?

1) Can you make it die while doing a brake stand?
2) At what speed did it die and were you accelerating?
3) What rev was it at and in what gear were you?

Possible faults:

Ground to the AS control circuit via
1) PCM (on purpose for an unknown reason)
2) Short on DK Blue lead to PCM (AS relay)

Partial OC to Fuel Pump Control

1) EGR LT Green Wire
2) VAP LT Green Wire
3) EVAP/ PURGE LT Green Wire


Other things will cause a shutdown but it is the error code 42 that make me suggest these circuits.

[palindromelol]

Loose fuse 21.. 20 A?

[das2123]

Replace your fuel pump relay and see if that takes care of your problem. Sounds like a fuel delivery issue. After that you may want to look at the fuel pump.

[NFarran]

The gear doesn't seem to mater, I've been in 1st though 5th and had it die. But it allways dies just after I shift in to another gear some times it will die shifting from 1 to 2, 2 to 3, and so on. I have tried to get it to die doing the brake stand until the tires end up braking lose and start thoughing rocks all over the place. HeHe. And yes accelerating seems to be when it shuts down. as for the rev i don't have a tac so I really have no clue. How would I check these circuits that you talk about Like I said I have pulled all the black tape and plastic conduit off of all the wires and looked them over very good before puting the tape and stuff back on.

[NFarran]

Oh and i have replaced all the relays with new ones, thats one of the things the dealer I talked to told me to check.

[palindromelol]

By the sound of things several potential causes can be eliminated or indicated. Lets do that.

1) The relays are perfect.
2) The fuses are perfect.
3) It is independant of speed.
4) It might be independant of torque.
5) It might be related to change on torque.
6) It might be related to change in speed.
7) Might be related to a change in fuel consumption.
8) Might be related to a change in air flow.
9) might be related to an change in vacuum.
10) It is not brake light circuit related.
11) It is not water related.
12) It is not auto trans clutch related.


This problem can be broken in half very quicky. It is either a fuel side or A/S side fault. To narrow it down it would be nice to know if it is a fuel control fault. ( Had a Fuel Pump Fail intermittantly then die... Keep that in mind)

Would it be possible for you to monitor the voltage on one specific wire during operation?

The wire I'd look at is the ground wire for all the injectors ignition coil pack and O2 sensors. If you could monitor, with a volt meter, that wire's voltage and determine if it dips or spikes during the fault and holds there until you turn off the vehicle. I hate to jump to conclusions. But I am guessing a fuel delivery fault or an errant ground in the ignition system. Can you tap into the dark green with orange stripe wire and continuously monitor voltage?

[NFarran]

I Found the problem, after messing with the wires for a few hours and pulling off the fuel filter. fuel filter was fine. I found that I do have a wire problem even though the wires all look good I have to rip the black tape back off and look them over again. Right now I have the wires pulled off the motor and the car is runing fine. So most likely grounding out, it maybe a bad plug. But anyway thanks for all your help.