No luck with MALF codes

[dBaseD]

Today while my wife was driving the Sy, the trucks CE light came on and she called me and let me know it came on and was hesitating badly at lights etc etc. I checked the code tonight and it was MALF42 so I figured the ignition module went bad. I put a new ignition module cap and rotor on, but the code remained so I checked the EST wire and there were no issues with it, but the truck was still hesitating and the CE light was still coming on. (I never checked the timing, but I assume it wasnt getting any advance considering the way it was running and the fact that it was code42)

So I decided that I might just need to clear the codes from the ECU to fix it, So I turned the headlights on, and disconnected the negative terminal on the battery for about 30 seconds to make sure any residual power in the ECU was drained. I shut the lights off and reconnected the battery and attempted to start the truck and it wouldnt even idle.

I finally got it to idle in park with some coaxing, and checked the codes..

Its now throwing codes 12, 14, 15, 21, 24, and 42. Any idea what broke? And beyond the other codes - any idea what else would cause the MALF 42? I checked the EST wire and its just fine, and I just replaced the ign module cap and rotor. I'm out of ideas at this point.

-Jason

 

[supersports10]

Re: No luck with MALF codes

bad ground....

bad ground....

bad ground....

bad ground....

 

[TYTILIDIE]

Re: No luck with MALF codes

Could also be your ECM takin a shit too.

 

[sly dvl]

Re: No luck with MALF codes

You my friend need an ECM. If you follow the trouble tree on a code 42 or 43 you'll find when you get to the bottom one of the last steps is "Replace ECM"

K

 

[dBaseD]

Re: No luck with MALF codes

You my friend need an ECM. If you follow the trouble tree on a code 42 or 43 you'll find when you get to the bottom one of the last steps is "Replace ECM"

K

I got all the other codes to go away now after disconnecting the battery again this morning, but the MALF42 flag still remains.

I used the timing light after I started it up, and it showed the timing as advanced the way it should be (~27ish) and no CE light on. I took the car for a drive around the neighborhood, got about 500 feet away from the house, and the CE light came on, I pulled it back into the drive and put the timing light back on it and the timng was at 0. I am starting to think the code 42 is being thrown because of a bad pickup or stator in the distributor itself. I have a spare memcal here, so I will try that next and if the MALF flag remains, I will likely replace the distributor next.

-Jason

 

[sly dvl]

Re: No luck with MALF codes

Follow a trouble tree (flow chart). No where will you find it condeming a distributor. It's either the ign. module, the ECM or the wiring in between.
Because you had several "phantom" codes I'd be leaning towards an ECM.
As previouslt mentioned it could be a bad ground but unlikely if all the other codes are now gone...

K

 

[turbodig]

Re: No luck with MALF codes

Today while my wife was driving the Sy, the trucks CE light came on and she called me and let me know it came on and was hesitating badly at lights etc etc. I checked the code tonight and it was MALF42 so I figured the ignition module went bad. I put a new ignition module cap and rotor on, but the code remained so I checked the EST wire and there were no issues with it, but the truck was still hesitating and the CE light was still coming on. (I never checked the timing, but I assume it wasnt getting any advance considering the way it was running and the fact that it was code42)

So I decided that I might just need to clear the codes from the ECU to fix it, So I turned the headlights on, and disconnected the negative terminal on the battery for about 30 seconds to make sure any residual power in the ECU was drained. I shut the lights off and reconnected the battery and attempted to start the truck and it wouldnt even idle.

I finally got it to idle in park with some coaxing, and checked the codes..

Its now throwing codes 12, 14, 15, 21, 24, and 42. Any idea what broke? And beyond the other codes - any idea what else would cause the MALF 42? I checked the EST wire and its just fine, and I just replaced the ign module cap and rotor. I'm out of ideas at this point.

-Jason

You didn't mention if it had a chip of some sort. The aftermarket chip carriers are notorious for bad connections, and loose PROMs. This will cause the symptoms you describe.

Bad ECM and/or grounds would be another.

 

[dBaseD]

Re: No luck with MALF codes

I replaced the distributor today. So far so good - no MALF flags yet. Once I had it out it was apparent from how rusted and oxidized it was, that at some point in its life it had gotten a significant amount of water inside of it. I would assume someone tried to pressure wash the engine bay or something along those lines.

Anyways, time will tell if that was the fix or not, though now it seems like it has a hard start spot ;P

Hopefully this wontbe a neverending tail-chasing endeavor.

-Jason

 

[sly dvl]

Re: No luck with MALF codes

Well that's what you get for having a Mustang as an Avatar on a SyTy forum... j/k

How complete was that dist.? Complete with module?

K

 

[dBaseD]

Re: No luck with MALF codes

Well that's what you get for having a Mustang as an Avatar on a SyTy forum... j/k

How complete was that dist.? Complete with module?

K

Haha! Fair enough. As soon as the SY is faster than the mustang - I will change Avatars

The dist arrived minus cap and rotor. Everything else was bolted on though.
So far so good with it, no problems at all over the weekend other than the aforementioned occasional hard start.

-Jason

 

[sly dvl]

Re: No luck with MALF codes

So the ign. module got replaced then. Let's hope that's the fix...

K

 

[dBaseD]

Re: No luck with MALF codes

So the ign. module got replaced then. Let's hope that's the fix...

K

Twice. It wasn't the ign module as I replaced that first to no avail. I think it was the stator or pickup in the distributor itself.

-Jason