Not again.

[phil_long]

anything around the water pump that could've gotten bumped or pinched that I'm overlooking? So far we know that the issue is during cranking and the ECM and MAF sensor itself can be eliminated...

[phil_long]

I've read a few posts over on the other board because I did a search. One guy found his TCC wire had shorted. I'm gonna get to unplugging some shit. Lol

[Steve Wood]

After looking at the diagrams, in theory, at least, this cannot be happening

Power goes into the ignition switch from a fusible link. When the key is in Run, it goes to the ecm-ign fuse.  When it is in Start, it goes to the starter solenoid and the ecm-ign fuse at the same time.

the solenoid is not pulling any power thru the ecm -fuse because it is on the front side of the fuse.

So much for theory, I guess.

The solenoid is the purple wire coming out of the ignition switch, goes thru the bulkhead connector, and goes to the solenoid.  If the purple wire, under the dash, has a bare spot in it and the wire going to the ecm from the fuse had a bare spot in it...then the current draw from the solenoid would pull some from the fuse and probably pop it.  I would think this is highly unlikely.

More likely, would be under the hood where the purple wire comes out of the firewall and runs across to the starter.  I have seen cases where the wiring bundle comes out of the firewall bulkhead and it forks-----this bundle is held up in the air by a stand off that goes over the valve cover stud.  When this plastic stand off breaks  the wiring bundle drops down until is laying on the valve cover...and that allows it to lay on top of the end of a long screw that comes thru the firewall...I think this screw is one of the accelerator pedal bracket screws.

The harness rubs on the threads of the screw and saws thru the insulation.   This can cause some really strange things like blown fuses, blown fusible links and cross circuited connections etc.  It is hard to see this screw but you can put your fingers behind the wiring harness and feel it..or pull the harness forward and see it.  Sticks out a fair distance.

At that point, you have wires from the maf, esc module, ignition module and a couple of jillion more.

I think I would look at that point and make sure the wiring bundle is not laying on that screw.

I would also be sure the battery had a full charge on it so it does not force things to pull more current than normal

If you don't find a problem with the wiring and the effing screw...discon nect the purple wire from the starter solenoid and see if it still pops the fuse when you hit start.

[phil_long]

Thanks for the response. I'm going to unplug the control module as well to eliminate that as a whole. No way a bad coil pack could cause this? Anything else to unplug and try before fishing through the sea of wires?

[Steve Wood]

Hmmm....I don't recall telling you to fish around thru a sea of wires...

Let me try again.

1.  Make sure the battery is fully charged

2.  Make sure the wiring harness is not laying on that screw where the harness comes thru the fire wall under the hood.

3.  Disconnect the purple wire from the starter solenoid if the fuse still blows after doing 1 and 2.


Because the fuse only blows in start, I am thinking its not a problem with the ignition module, maf, ecm, and probably the esc module but I do note that you did not mention disconnecting the esc module in the first go round.

[phil_long]

I was joking Steve!!!!

[phil_long]

So I unplugged the control module, ecm, scanmaster, and the MAF. Key on, engine off, fuse was ok. Plugged the Control module back up, key on, engine off, fuse ok. Plugged the ECM back up, the damn car started.   So i plug everything else up, and the car is running just fine. Im so pissed because I don't know what the hell happened or what I did. This car has never ran so quiet!! No more leaks from the coolant, and I'm ordering a new serpentine belt to the right sized one. I did check around where you told me to check Steve, and that wiring harness appeared to be fine. I'm losing my mind here. I do think I might invest in some new fans though, because the car runs a little too warm for the thermostat that I'm running. After driving around and giving some throttle, the temps got up to about 183. Seeing that the temp outside is only 62* and my thermostat is a 160, that's a problem. The fans dont sound like they're running as hard as when I first purchased them.

[Steve Wood]

So either charging the battery fixed the problem (first thing I always check is the battery charge level)

Or moving the wiring bundle when  you checked it...

looks like one of the two "fixed" the problem...

[phil_long]

Yup! I want to look into it further I think. You'd be proud! My lazy behind finally cleaned my air filter. Now back to chasing down routine issues. Lol. Thanks a lot for the help Steve.

[phil_long]

I'm convinced that the low voltage is what is blowing the fuse. Not sure how or why, but I allowed the car to sit after driving for a week and half everyday straight, and I go to turn it over and low and behold the fuse pops again(battery died). I'm sure its time for a new battery as I've had this one for many many many years, but I just thought it was odd that a drained battery would cause the fuse to pop.

[TexasT]

In theory, low volts will require more amperes to do the same job. More amperes than the fuse wanted to pass apparently. At least that's my theory.

[phil_long]

And that's exactly what the problem was. The battery has a bad cell. Car is up and running perfectly fine now. 

[Steve Wood]

in the old days, we just rolled it off and popped the clutch...moder n cars have to have a good battery

[phil_long]

gotta love the good old days

[Steve Wood]

Life was so simple and it looks really good to me now!