Need an engine wiring schematic

Does anyone know of any sites that have engine wiring schematics?

Our local library has internet access to a few web repair manuals such as chiltons. Do you have a specific question we might be able to help you with?

I found a melted wire and I`m trying to find out the correct way that it should be connected.

I have a 1993 maxima, the melted wire is a yellow/green wire that comes from the variable valve timing selenoid but it looks like someone cut the wire and spliced a large red wire to it and then grounded the red wire to the engine block.The plastic on the end of red wire, where the wires are spliced, is melted.They left the end of the yellow/green wire that is connected to the selenoid connected to nothing or maybe it too was connected to the ground wire at some point,but it`s not connected to anything now.

I dont know why they would do that unless they were trying to bypass the VVT or something ,so now Im wondering should I reconnect the 2 ends of the yellow/green wire back together or should I connect one end of the yellow/green to the ground wire or should I connect both ends of the yellow/green to the ground wire.
Obviously when the car came from the factory the yellow/green wire was one continuous wire inside a wire harness.

The reason I was even checking those wires is because after the engine is warm the car is really hard to start almost like the timing is off, but it starts right up after it has sitting for awhile and the engine is cold.


If you “join” autozone on the website, you’ll have free access to some information, including wiring diagrams

It’s not the greatest, but it’s free

They won’t ask for your social security number or your credit number . . .

@db4690 Thanks! Autozone had it,
that wire isnt suppose to be grounded so Im going to reconnect the ends together and get rid of that ground wire and see what happens.
I remember reading that on this engine the VVTs had a problem with making a lot of tapping noise maybe thats why someone grounded it to bypass it or more likely it stopped working and they didnt want to buy a new one.Ill find out tomorrow when I reconnect it and take it for a drive.


Glad to hear that the autozone technical website was able to help somebody

And good luck!

They’ve come a long way since the days of Auto Shack, @db.

But I still don’t trust their brakes

Twice I’ve bought brakes, and each time it was an unsatisfying experience

One time, the brake pads simply wouldn’t fit right, even though we checked, and they were supposedly the correct parts for my application

Another time, a set of brake rotors were warped . . . right out of the box

As with any parts, with time you figure out what brands are okay to buy, and where it’s okay to buy something

that’s good to know, I was gonna check auto zone tomorrow for brakes. they have a bunch of kids working there who know little but I figured it would be ok for brakes. the napa near me has a couple good guys but I am not paying double what pep boys charges for parts that aren t as good.

looks like I m burning the gas in old blue to go to pep boys, wish they were closer…

Napa is far from perfect, but I’ve not run into problems with their brakes

Speaking of Pep boys brakes, I’ve bought Proline brakes and raybestos there. No problems

I have to say I just bought brake pads a month ago for my f150 from napa. I bought the most expensive ones because I’ve been miserable enough using cheap pads on previous cars. These were their ceramic I think for about 70-80 bucks. I really have to say they’re great. Quiet, strong, and no overload of dust. Money well spent.

yeah, the only bad parts I have gotten from napa are batteries, the last two only lasted 2 yrs. my main complaint with them is price. I like pep boys for parts, they are often half the price of napa and are in stock more often.

I like the hard pads too, they do a good job turning rotors :slight_smile:

I’ll go a little off topic

I agree that Napa batteries are an absolute joke

One time I bought a battery for my Tercel. I installed it in the store parking lot. It didn’t fit worth a darn

I immediately took the battery back into the store, and told the guy I needed my old battery and my money back, because his store brand battery didn’t fit

He gave me my old battery back, but he wasn’t able to give me my money back. Somehow, his cash register didn’t have enough cash. Huh? He told me to hang on to the receipt and come back in an hour, after some more customers had hopefully made purchases.

I reinstalled my old battery (wanted to replace it because it was getting weak, old and leaking). Then I went somewhere for an extended lunch, before heading back to Napa. I got my money back and never went back there again.

A few years later, the store was out of business. I think the real problem was the location. It wasn’t in an area of town where you’d expect an auto parts store. Right next to it were thrift shops, shoe stores, a bank, etc. And the parking was in the back, which meant you had to know how to get there, from a previous visit presumably

And yes, I’ve also noticed that Napa batteries don’t last long. Many of them don’t even make it past 2 years. That’s probably why Napa generally doesn’t warranty their batteries past 2 years.

I reconnected the ends of yellow/green wire and removed the ground wire.I removed the 2 V.V.T solenoids and checked to make sure none of the oil passages were blocked, they looked fine so I put them back in.
I took the car for a 20 minute test drive and it ran noticeably better.Faster acceleration and smoother running in general.
Now I`m left wondering why the heck did someone cut the wire and ground it?

Thats not the first strange thing Ive found that someone has done to the car.
Someone cut the cables for the rear window motors.The ends werent frayed the cables and the plastic shield around them had nice clean cuts all the way through. someone disabled the trunk release on the drivers arm rest. someone rerouted the radiator overflow hose so that the end of it was positioned directly over the fan.When water came out of the hose the fan blew the water all over the engine. They painted all the chrome trim, on the outside of the car, black. There were a couple other odd things that I found and fixed, I dont remember off hand what they were though.


Congratulations on a successful repair!

Sounds like a COMPLETE idiot owned the car before you

Those things they did make absolutely no sense

Perhaps the guy who did all that stuff was a dope fiend

That’s the only explanation that makes sense

I always bought brake pads from NAPA with no problem. I usually got the middle of the line because I was afraid of having noisy brakes. I had an issue with a set of rear shoes once but the replacements were fine. My last pads were just Delco OEM though with NAPA rotors.

Obvious the previous owner didn’t have a clue. I wouldn’t fret over why they did what they did. They don’t know why they did it. The car is happy now that it’s in caring hands

My thought on those bad mods on the car. the person who did it probably sold it because it had so much wrong with it, and had no idea why.