MAF 20a fuse

[MDMike]

Noob here w/ 98 base Catfish, 3800, M5.
If my 20a fuse for Engine Sensors keeps popping, and I get P0102 MAF codes, is the MAF itself causing the fuses to burn because it needs replacing?

I'd hate to buy a MAF if my fuse will keep popping; I have cleaned the ground connection, and the plugin seems okay. Ive cleaned the MAF with CRC also.
Thanks.

[Joe 1320]

Disconnect the MAF and replace the fuse. If it still pops, then it's not the MAF.

[MDMike]

Thanks.
Did that with the MAP also; no change, still popped.

[FroSSty]

It sounds like a wire is arcing.

[MDMike]

the harnesses over the bell housing are tough...

It sounds like a wire is arcing.

indeed.
I've got to track it down; two of the O2 leads were arcing, one melted to the Y-pipe. I have now isolated them, but the harnesses over the bell housing are tough...
Thanks

[MDMike]

eliminating culprits

Last night I bought a cheap 25ct pac of 20a fuses.
I'd insert a new fuse in the ENG SEN spot where they'd been burning, then I'd remove the elec connector from ea emmisions and fuel sytem sensor I could, incl MAF, MAP, AIT, and such.

The 20a ENG SEN fuse continues to pop whenever I turn the key to ON, nomatter what sensor I disconnect.

I checked the grd wire on the fr of the block near the balancer, and on the left rr side under bank 1 O2 sensor.

I have looked at all the schematics on these sites and in the manual, but seem to show exactly where the ground wires connect. Grd numbers like 110 do not help if you have no diagram showing #110's location...

Since the engine swap, I cannot get to the harness behind the block, above the bellhousing and between the firewall that the O2 sensors plug into. But when I reach my hand back there, I can grab or feel a dead end connector of some type.
Any ideas what this could be, and/or what I should look for back there, either from below or above?

I do not beleive replacing the MAF, MAP, etc., will keep that fuse from popping, but I cannot get codes if no current is reaching the sensors! I have replaced the O2s, and they are clean and connected...

Thanks again. The usual searches where attempted...

[Jeff_in_Atl]

This may be a long shot but could you have pinched the wiring harness between the engine and the transmission?

Can you get a hand mirror and look back there?
This is the picture of the back of my engine with the trans removed. The only harness I see near there is on the drivers side as you see.

[MDMike]

mirror!

Nice picture. I realize that I may not have stated I have a 98 catfish, 3800 v6, 5sp manual!
But thye could have simular harnesses...
In any event, something is sticking up dead-ended back there, and yr mirrior idea is great. Thanks, will try it tomorrow on my day off.

You think a bad ground, a short, or an unplugged sensor connection is my problem?
I guess I'll start shopping a good auto electrics shop in MD/DC...

[Jeff_in_Atl]

From what you have said it can't be a bad ground or a bad sensor. It has to be a short to ground.

[MDMike]

Yr correct; finally found the short to O2 aft of the cat!
Still get the MAF code, so one is coming UPS now, Thanks agin all...

[MDMike]

P0134

New Maf got me on the road.
After ~100 miles tho, it threww P0134, O2 No Signal.
All my harnesses and grounds are hooked up and clean, and the O2 is new.
Could it be anything else but a short in the harness?
Are harnesses still sold new OEM?
Thanks.

[MDMike]

New wires and now my #2 O2 is low current.
Good thing I am off tomorrow...

[Injuneer]

According to the 98 Owner's Manual, there are several things on the same fuse as the MAF sensor, one of them being the O2 sensors. Had you previously ruled the O2 sensors out as the source of the blown fuse?

Mass Air Flow, Heated Oxygen
Sensor, Skip Shift Solenoid (V8
Only), Reverse Lockout Solenoid,
Brake Switch

[MDMike]

Thought I did, but found a short on Bank2 #1; replaced, catfish runs good, Ck Eng lite is off, time for MD Smog Inspect.
Thx agin...