Electrical issues running amuck
Thread Starter
Le Mans Master
Joined: Dec 2003
Posts: 5,768
Likes: 33
From: Van Steel Corvettes
St. Jude Donor '12-'13
Electrical issues running amuck
So it seems I keep adding things to my electrical problems. Started off with the drivers door switch and hatch release switch stopped working. Along with that my cd deck has to be turned of manually as the door switch can't turn it off. Also been having a very erratic oil pressure gauge. Lately I've added an EGR code and the bank one sensor one O2 sensor heating element code going off.
While working on the car today, I noticed the ecu was VERY hot. Now it is hot outside, but it was too hot to handle and the hood has been shut, but in the sun. Could the ecu be causing all these issues? I've checked the ground that most, if not all these elements have in common. It was oily, but sung. Loosed it up, cleaned it off, and snug it back down. I also notice that the MPG is about 10mpg off now. On my drive home Friday, was showing 13mpg were I normally get 23. The car has a slight rough idle, but runs great under throttle.
While working on the car today, I noticed the ecu was VERY hot. Now it is hot outside, but it was too hot to handle and the hood has been shut, but in the sun. Could the ecu be causing all these issues? I've checked the ground that most, if not all these elements have in common. It was oily, but sung. Loosed it up, cleaned it off, and snug it back down. I also notice that the MPG is about 10mpg off now. On my drive home Friday, was showing 13mpg were I normally get 23. The car has a slight rough idle, but runs great under throttle.
Thread Starter
Le Mans Master
Joined: Dec 2003
Posts: 5,768
Likes: 33
From: Van Steel Corvettes
St. Jude Donor '12-'13
Pulled the negative battery cable last night to make sure the ECU is completely reset and noticed that I can no longer snug the neg battery cable down all the way. The battery post looks to be stripped out. Any snow ball chance in hell that could cause these issues? The battery is about 3 years old and will be due to be changed soon anyway. Looking into a lightweight drycell battery.
Safety Car
Joined: Jun 2003
Posts: 4,250
Likes: 656
From: San Diego Ca
Very possible. Let us know how it works with a repaired or new battery or battery cable, however I don't think that is your only problem, but you need to fix it to get to the source of the electrical short.
Burning Brakes
Joined: Apr 2011
Posts: 917
Likes: 25
From: College Station Tx
Seems to me that you just need to replace the door switch and an O2 sensor(s). If the switch doesn't work properly, the car thinks the door is still closed, so the deck won't shut down and the hatch won't open. Your interior lights probably won't come on either. One thing you can do is open the door, pull/wiggle the switch, see if the deck shuts down.
If you have a bad O2 sensor, it can really kill the fuel mileage. So, to me, very little is pointing to the ECM and or battery.
If you have a bad O2 sensor, it can really kill the fuel mileage. So, to me, very little is pointing to the ECM and or battery.
Thread Starter
Le Mans Master
Joined: Dec 2003
Posts: 5,768
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From: Van Steel Corvettes
St. Jude Donor '12-'13
Door switch, hatch switch and O2 sensor where already replaced. Sorry, should have mentioned that. The oil pressure sensor started acting up a few months after being replaced and had it replaced again under warranty. Still is very erratic. It still all seems to point to the ground on the bell housing, but I know it's good...unless something is going bad in-between (but the wires "looked" to be in-tacked looking up along the harness) and I'm pretty sure the ECU is all intertwined with it as well.
I have the dash out, along with most of the interior trying to hunt this damn thing down. Only other thing that I could remove at this point, to make things easier, is the stinking motor. Uggg.
I have the dash out, along with most of the interior trying to hunt this damn thing down. Only other thing that I could remove at this point, to make things easier, is the stinking motor. Uggg.
Last edited by shakedown067; Jun 27, 2013 at 08:47 AM.
Burning Brakes
Joined: Apr 2011
Posts: 917
Likes: 25
From: College Station Tx
Ok..so I don't make any more assumptions, do the new door and hatch switches operate correcly? If not, have you tried unplugging the door switch and putting a meter across the socket just to see if it has a good ground? I know this is the least of the worries, but if it is a grounding issue, that is the quickest and easiest starting point.
Thread Starter
Le Mans Master
Joined: Dec 2003
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From: Van Steel Corvettes
St. Jude Donor '12-'13
Yep, if you ground out the proper ground wire, they work. I actually grounded the wire to the ground right by the drivers door. But booth the door switch and hatch switch run the same ground that go to the PKE and CCM which go to ground 205 (or 206, whichever is on the bellhousing), or so the FSM says.
I've actually been looking into complete interior and motor wiring harnesses, not that I want to go down that road.
I've actually been looking into complete interior and motor wiring harnesses, not that I want to go down that road.
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Burning Brakes
Joined: Apr 2011
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From: College Station Tx
Do you have any aftermarket devices installed that may be screwing with things? Also, have you noticed any weird interactions between components (i.e. a/c, stereo) and the drivers display?
Thread Starter
Le Mans Master
Joined: Dec 2003
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From: Van Steel Corvettes
St. Jude Donor '12-'13
Not really. Every now and then when turning the A/C on the button takes a 10-15 seconds to light up (which tends to happen before the battery goes out). Other than that, everything seems to run fine. The only aftermarket component is the Alpine Deck. Ah, it did have an aftermarket alarm in it, but it was removed a couple of years ago. And all of it's connections shy of power, where just snap-t connected. Was pretty easy to remove and again has been quite a while. The exhaust shop did burn one of the trans harnesses and had to solider a few wires back together, but that too has been almost three years ago. It is one of the things I was going to check this weekend. Trans runs just fine though.
My main goal right now is to try to rule out a lot of potential issues. I've got a good electrical guy, but he's not exactly cheap...and I'm trying to actually save some money these days.
My main goal right now is to try to rule out a lot of potential issues. I've got a good electrical guy, but he's not exactly cheap...and I'm trying to actually save some money these days.
Thread Starter
Le Mans Master
Joined: Dec 2003
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From: Van Steel Corvettes
St. Jude Donor '12-'13
Ordering a die hard today ($40 off today). Looks like bank 2 sensors 1 and 2 are throwing codes now as well. They haven't been replaced in a long time so I'm going to go ahead and replace all the o2 sensors. EGR purge valve is cheap from rock auto and was very dirty so I'm going to order that as well. So those may just be completely unrelated to my electrical bugs. Which would be good news...or the car is just going to hell and will be parted out!
Thread Starter
Le Mans Master
Joined: Dec 2003
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From: Van Steel Corvettes
St. Jude Donor '12-'13
Just FYI, my last ses code was bank 1 sensor 1. Replaced that o2 sensor and haven't gotten that code again. So maybe it's just old car syndrome.
Burning Brakes
Joined: Apr 2011
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From: College Station Tx
Thread Starter
Le Mans Master
Joined: Dec 2003
Posts: 5,768
Likes: 33
From: Van Steel Corvettes
St. Jude Donor '12-'13
FOUND MY ISSUES. Pulled the transmission yesterday to have it rebuilt and found two ground wires broken in the wire harness behind the block (going to the ground on the transmission engine bolt). So I should be knocking out three birds with one stone when I get the trans back!
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
FOUND MY ISSUES. Pulled the transmission yesterday to have it rebuilt and found two ground wires broken in the wire harness behind the block (going to the ground on the transmission engine bolt). So I should be knocking out three birds with one stone when I get the trans back!
Thread Starter
Le Mans Master
Joined: Dec 2003
Posts: 5,768
Likes: 33
From: Van Steel Corvettes
St. Jude Donor '12-'13
Yep, I suspected it was a ground issue as well, but after checking and cleaning that ground previously, it looked ok. It was only after I pulled the trans that I could see where they were broken in the wire loom. I was really afraid it was going to be much deeper in the wire harness. So NOW it should be quick and easy!
So, where did I put that soldering iron. LOL
So, where did I put that soldering iron. LOL