420A Electrical problem after rebuild and engine start.

[Casey Deckers]

So I just finished doing a bunch of work on my 98 eclipse gs, replaced piston rings, rod bearings head gasket, other various gaskets, and some timing components, this is my first project car and I wanted something relatively easy to work on and try to bring back to life. After replacing the IAC valve the car went from a rough idle to a much better and smoother idle, to the point where I could finaly take it for a drive. Took it to an autozone and got the engine light checked and it read P0106, a MAP sensor problem which made sense since the idle was still a little rough.

I had enough confidence to take it to the store the next day, I tried to turn the key, I got a crank and no start, also noticed that all the dash lights on the left side stopped working, the power windows and sunroof as well as the keyless entry, stopped working, so I ended up towing the car home, luckily it was only a few blocks. Weird thing is that the elctronic door locks work and the headlight/taillights, the wipers etc.

I am new to cars but it just suprises me how this car can go from running pretty well, better than it has in months, to just not running at all. I checked the fuse box in the engine bay and the one under the dash and all the fuses there appear to be good. The only thing I can think of that I should mention is that the last owner installed an aftermarket Clifford security system that has wires going all throughout the car.

If anybody has an idea of what I should check, I just dont know what could have happened. I was in the store for ten minutes and when I came out everything just stopped working.

 

[CKOPOCT]

I would start by checking grounds. The Clifford system shouldn't of itself cause this issue, unless the PO wired it wrong. Enev then it shouldn't be intermittent... which is why I say check your grounds - specifically to the ecu. With 1/2 of the dash lights being out makes me think the harness may have been hacked or the dash may have been pulled off. I believe the instrument cluster and internal harness have several ground wires that bolt to the frame just under the dashpad right under the windshield. Not suggesting you dive right into pulling the dash off of the car.

Check easy to reach grounds and connections in the engine bay and front cab. Report what you find.

 

[Casey Deckers]

Dont know if this means anything, the left side pin connection was reading lower than the others.

Also for the other ground connections, where exactly am I supposed to be looking?

You must be logged in to view this image or video.

You must be logged in to view this image or video.

You must be logged in to view this image or video.

 

[BLACK'98DSM]

I see a lot of corrosion on that connector. Which could mean a bad connection. Not just there, I wonder what all the other exterior connectors look like. I would start by cleaning / replacing those as necessary.

Another thing I noticed is that your ground strap is connected the wrong way. The end that currently goes to your battery is supposed to go to the starter, and the other way around. It's just a wire so direction of electrical flow does not matter, but those harsh angles will cause the joint to wear faster. And if that is wired backwards then what else is.

 

[Clipsoe]

@BLACK'98DSM Are you referring to the ground wire from battery to chassis and starter? That's the OEM wire on the 420a. It comes off the battery, goes to chassis by shock tower first, then off there to the starter. It's right.

@Casey Deckers I would get a loaner scan tool and see what codes its throwing, if it's throwing any. Besides the P0106, since it stopped working after the last scan.

 

[BLACK'98DSM]

@BLACK'98DSM Are you referring to the ground wire from battery to chassis and starter? That's the OEM wire on the 420a. It comes off the battery, goes to chassis by shock tower first, then off there to the starter. It's right.

This is the factory routing for that wire. Some off the shelf battery cables were backwards like that.

You must be logged in to view this image or video.

 

[Clipsoe]

That's exactly what it looks like he has there...mine bends down before the shock tower and goes along the side of the battery to the starter. I think it just looks weird with his pic, especially since they are twisted.
@Casey Deckers can you post another photo of your battery/ shock tower so we can see how the cable is routed.

 

[Casey Deckers]

That's exactly what it looks like he has there...mine bends down before the shock tower and goes along the side of the battery to the starter. I think it just looks weird with his pic, especially since they are twisted.
@Casey Deckers can you post another photo of your battery/ shock tower so we can see how the cable is routed.

You must be logged in to view this image or video.

 

[Clipsoe]

Yep, it's right, it's just the wires are all twisted.

 

[waltah]

/// all the dash lights on the left side stopped working, the power windows and sunroof as well as the keyless entry, stopped working, so I ended up towing the car home, luckily it was only a few blocks. Weird thing is that the elctronic door locks work and the headlight/taillights, the wipers etc.

This sounds like a fuse. Second to that, a wiring issue.

I am new to cars but it just suprises me how this car can go from running pretty well, better than it has in months, to just not running at all. I checked the fuse box in the engine bay and the one under the dash and all the fuses there appear to be good.

Fuses are like some other things in life: "Looks okay" is not reliable. Get a multimeter and check them, starting in the engine compartment since that's where the stuff that controls whole groups of functions lives.

It'll save you some time if you find the online service manual and look at the power distribution diagram for your car. Take the list of what doesn't work and look for the place(s) where all that could be shut off by one failure.

As to 'can go from running pretty well ... to just not running at all' you may see that again a few times as you plow through the problems that previous owners couldn't/didn't want to fix. A GS is slighly simpler than the GS-T/GSX but that doesn't make it a simple car, even among '90's Mitsubishis.