GISguy

I'm sorry if this has been asked before but it's a little confusing when I read about it..

Earlier today after leaving the car off for about 2 hours, I enter it, turn the key a bit, and then everything dies. No power or anything. If I open the door, there is no puddle light, no dome light, nothing, only a very dim "door open" light on the cluster fading in and out slowly.

Close the door, wait a minute or two panicking, then open the door, and suddenly all power is back to normal, and the car starts normally.

Later on at night, I do the same thing; park it for 2 hours, come back...car starts up just fine, put it in reverse, start going back at 5mph, and then...dead. No power or anything, car is just rolling. I put it into park, turn the key off, and it's in the same state. No power, just the dim "door open" fading in and out slowly.

Once again, I wait a minute, and it starts up again. This time I'm driving along out of a friend's neighborhood trying to get home quickly, and at a stop sign, the car dies, again. This time, all things electrical seem to still have power, until I pull the keys out. Put them back in, and once again, nothing. All lights dead. I'm sensing a pattern that it seems to die at idle/low RPMs.

Wait a minute or two once again, and then once it starts, I start revving it up like crazy. Every stop light, I put it in neutral and rev to 3-3.5k, then put it into drive to keep it alive. Did this all the way home.

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

I've read about the bad fuel pump ECU issue and as such, I have a new one in my emergency parts bin ready to be put in. But are these symptoms indicative of that? My first thought was that this is a bad alternator, failing to charge the battery and failing while driving. The car runs off of the battery until the engine starts up, correct? And then the alternator kicks in.


I should note that every time it loses power, the radio and clock are reset, and it performs an idle re-learn.


No misfires, no CEL. Just a complete loss of power. Engine turns off ,car turns off, no power to anything for about a minute.

Mike1JZ

Have you tried the fuel pump ECU bypass yet? That will help determine if it is your problem. (Bridge "FP" & "+B" of diagnostic port under the hood with a paperclip)

When my original was on it's way out I experienced the same symptoms you mentioned to the point of the car not starting at all. I used the ECU bypass to get me by until I purchased a new replacement.

All the best.

GISguy

I guess that's my question....did the fuel pump ECU cause you to lose all power completely? Not just engine stall, but all electrical.

EDIT: Just replaced my 20-year-old fuel pump ECU and my 4-year-old battery. We'll see how it goes.

Mike1JZ

Everything, a complete reset as you described. Anywhere from a few seconds to minutes, unpredictable each time.

Good luck with the replacement, I would be dumbfounded if it wasn't the issue!

scrapinls

RXRodger

iTrader: (2)

The fuel pump ecu would not cause all power to go out like that, it would only cause loss of fuel from the pump. Need to look elsewhere in my opinion.

What year car are we talking about here?

Edit: Without tracing down the power circuit flow, my initial guess is problems with the ignition switch. The only thing that counters that is you say it does an ecu relearn which says total loss of power. Maybe something like bad connection in the main fuse panel?

AngeloPast

Did you ever figure out the issue. Bcuz I've changed the main ecm with a new one and it didn't work. New spark plugs and wires, new fuel pump and filter, new intake, manifold cleaned out, new battery, new alternator, new maf sensor...the list goes on. -_- but I ain't selling the car bcuz I love it.