[dana44]

Well, my new son-in-law bought a pretty nice looking 2004 Mazda 626 with a 3.0 V6 automatic and it was smoking a little bit, and using a whole lot of oil (like a quart every 150 miles), so, since he and the daughter liked the car,I said, let's just do a quick rebuild of the heads, check everything else. He wanted to learn a little more about the mechanical side of things, so I said sure to an inexpensive build. Every piece in the engine has Ford stamped on it, so I thought not a really big deal. It turned out to be seized oil rings from the bad seals so it got completely rebuilt for that "learning experience in the end).
Got it apart, put back together, installed, and now the fun stuff begins. 14 years and 200,000 miles basically destroyed the layout of the wiring harness itself and this is where I need the help. I have to re-wrap and replace most of the wiring harness covers because of the heat damage, wires themselves are OK.
I know where all the sensors are, but a wiring diagram for the engine bay is needed. Last thing I want to do is get sensors plugged in wrong (some of the plugs are similar, and I need colors of the wires to ensure things get in the right order, like COPs and O2 sensors, along with most of the other sensors.
Can anyone help with this? A Haynes manual (rather worthless) does not cover engine bay. Much appreciated.

 

[ImperialCrown]

A larger public library may have Motor's or Mitchell's manuals which show wiring diagrams and color codes. I was surprised to find some factory service manuals at the downtown library.
The public library book loan is free. Photocopy what can't be taken out. Some libraries may have a subscription to Alldata. Typical is 15 minutes for a reasonable charge and you can print page copies.
Support your local library system.

 

[AllanC]

. . .I know where all the sensors are, but a wiring diagram for the engine bay is needed. Last thing I want to do is get sensors plugged in wrong (some of the plugs are similar, and I need colors of the wires to ensure things get in the right order, like COPs and O2 sensors, along with most of the other sensors. Can anyone help with this? . . . .

I performed a search on 2004 Mazda 6 wiring diagram and arrived with these results.

MAZDA ELECTRICAL WIRING DIAGRAM WORKBOOK - Wiring Diagram Service Manual PDF (at https://freewiringdiagram.blogspot.com/2016/11/mazda-electrical-wiring-diagram-workbook.html )

https://www.mazdabg.com/ftp-uploads/Mazda/6/Mazda6 (GH).pdf

http://www.alarmsellout.com/support/diagrams/vehicle/MAZDA 6 2003-2005.pdf

You can go to www.bbbind.com and access free wiring diagrams. You have to set up an account (free) and then use the provided link to search for the year, model vehicle and wiring diagrams. Also use autozone.com. Set up an account, enter vehicle desired, and then go to
repair help --> vehicle repair guides --> wiring diagrams.

You may have to use various resources to get the detail information but I believe it is available but requires some searching and reference.

 

[dana44]

Thanks for searching for stuff guys, a couple questions were answered, but I think I am going to have to take a second visit to the junk yard that has a couple V6 engines with wiring attached and do pictures and diagrams. Everything I see online looks OK, but misses either colors to connectors/sensors, or is for a four cylinder engine, which doesn't help when I have two more cylinders so appreciate the help.

 

[85lebaront2]

Dana44, if you still need the diagrams I have AllData Pro and can print out diagrams or save them as a pdf and either convert to jpeg or just upload if the site will allow it.

 

[dana44]

Thanks, but I did the next best thing, went to the junkyard and was able to find enough examples to pinpoint the problems I was having, writing down colors and routing diagrams, along with a couple pictures. I just found it kind of odd that there was nothing really available for the engine bay itself, but I thank you for your search.
I was just about to post that I got it figured out.

 

[dana44]

I thought I would give an update on this project since some of you guys tried to help. I got everything back together after a trip to the junkyard, drawing pictures and the likes, identifying color of wires, etc.. Corrected a broken water temp sensor (expensive little sucker), then pulled the fuel pump fuse to prime the engine a little bit before starting and nothing. Put the fuse back in, cranked the engine for three seconds and she started right up, rattled for about another three seconds and idled. All in all, a miserable project compared to Mopars, that I will say, but another used and abused car is back on the road. Thanks for the help, it's the effort that means the most to me.
In the future, and I highly recommend, pictures or hand written notes of the wiring colors and routing, internet pictures and videos did not help me very much, and I never did find any wiring diagram online or in a book, although everything NOT under the hood was documented, the only exception being the charging system wiring diagram, so be prepared if doing any project like this.

 

[85lebaront2]

Just for grins, I looked at my AllData, there are 8 pages of powertrain wiring diagrams and 8 pages paired with them of routing. I did have what you needed, just didn't see it soon enough to help you with it.

 

[dana44]

Just for grins, I looked at my AllData, there are 8 pages of powertrain wiring diagrams and 8 pages paired with them of routing. I did have what you needed, just didn't see it soon enough to help you with it.

Appreciate it, but I needed to learn a lesson on new cars. I had promised myself not to do any work on foreign cars (Japanese, that is) that is new because of stuff like this, but it was for the son-in-law and daughter, so I sucked it up. When he brought over the Haynes manual I saw wiring diagrams, forgot to read the illustrations and realize it did not cover the engine bay, so it was a teachable (and learnable) moment for the SIL and myself in what not to do with newer cars. My asking for help in finding the diagrams was the easy way out and in the future will know better than to rip things apart and expect them to go together easy like the old cars I'm accustomed to. Again, I appreciate, and why I stay current with Allpar, most everyone here is friendly and helpful, which isn't always the case on some other sites.