C5 electrical problems?
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I haven't really followed C5 stuff other than powertrain, but heard someone say recently that the C5's were electrical nightmares. Any truth to this? They mentioned something about the window switches in the doors.
Been thinking about selling my car again and moving to a Vette. Had it for 10 years and it's time for something different.
Been thinking about selling my car again and moving to a Vette. Had it for 10 years and it's time for something different.
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I've had mine a little over 2 years only thing I've noticed is lights on like the radio or on the dash flicker a little every once in a while, and they get brighter when i rev the engine but no major problems.
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I too have had 2 c5s. For a total of 10 years. These cars a rocks. I mod them and drive them hard. Take care of them and they look brand new in and out. Their light and beat cars that have more horsepower.
Only electrical things, some very few cars might have the injector wiring harness rubbing thru against the rear of the head, a few cars had the ddoor harness stretch out. There's a few grounds, just keep em clean. Personally I never had any of these problems, only problem I had, was the intermittent no start. I took the ignition switch apart, cleaned it, like new. I could buy a c6z or whatever, but the c5 rocks!!!
Only electrical things, some very few cars might have the injector wiring harness rubbing thru against the rear of the head, a few cars had the ddoor harness stretch out. There's a few grounds, just keep em clean. Personally I never had any of these problems, only problem I had, was the intermittent no start. I took the ignition switch apart, cleaned it, like new. I could buy a c6z or whatever, but the c5 rocks!!!
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I too have had 2 c5s. For a total of 10 years. These cars a rocks. I mod them and drive them hard. Take care of them and they look brand new in and out. Their light and beat cars that have more horsepower.
Only electrical things, some very few cars might have the injector wiring harness rubbing thru against the rear of the head, a few cars had the ddoor harness stretch out. There's a few grounds, just keep em clean. Personally I never had any of these problems, only problem I had, was the intermittent no start. I took the ignition switch apart, cleaned it, like new. I could buy a c6z or whatever, but the c5 rocks!!!
Only electrical things, some very few cars might have the injector wiring harness rubbing thru against the rear of the head, a few cars had the ddoor harness stretch out. There's a few grounds, just keep em clean. Personally I never had any of these problems, only problem I had, was the intermittent no start. I took the ignition switch apart, cleaned it, like new. I could buy a c6z or whatever, but the c5 rocks!!!
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I too have had 2 c5s. For a total of 10 years. These cars a rocks. I mod them and drive them hard. Take care of them and they look brand new in and out. Their light and beat cars that have more horsepower.
Only electrical things, some very few cars might have the injector wiring harness rubbing thru against the rear of the head, a few cars had the ddoor harness stretch out. There's a few grounds, just keep em clean. Personally I never had any of these problems, only problem I had, was the intermittent no start. I took the ignition switch apart, cleaned it, like new. I could buy a c6z or whatever, but the c5 rocks!!!
Only electrical things, some very few cars might have the injector wiring harness rubbing thru against the rear of the head, a few cars had the ddoor harness stretch out. There's a few grounds, just keep em clean. Personally I never had any of these problems, only problem I had, was the intermittent no start. I took the ignition switch apart, cleaned it, like new. I could buy a c6z or whatever, but the c5 rocks!!!
THIS imo
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I have two C5s. The 2000 is a full race car and the 98 is my daily driver. The only electrical problems I have had, I have had on both cars. The fuel gauge began to give a faulty reading. It climes as the car gets hot. However, I fixed this problem on the race car by going to a fuel cell. IMO, C5s are a tremendous value for the dollar.
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Opps, forgot about the fuel sending unit getting gummed up. Some guys use seafoam, etc in the gas tank every 5000 miles. I had that happen years ago, i used BG44k in the tank, sending unit started working great. I now use either bg44k or gumout injector cleaner every once in a while. I never had this problem again.
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I have an 02 coupe with the grounding issue that occasionally makes the car go into limp mode. Easy to reset, but yes, a huge peeve of mine. My 01 GM blazer has a grounding issue too, go figure. But it only causes a dash light to go on, not make the car drive like crap.
My vette is moddied, and I wouldn't DD it with the cam and clutch it has. A stock one would be a great DD imo. I haven't driven a stock one, but heard you would want to at least get a short shifter for the DD as the stock ones kinda suck im told.
My vette is moddied, and I wouldn't DD it with the cam and clutch it has. A stock one would be a great DD imo. I haven't driven a stock one, but heard you would want to at least get a short shifter for the DD as the stock ones kinda suck im told.
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I have two C5s. The 2000 is a full race car and the 98 is my daily driver. The only electrical problems I have had, I have had on both cars. The fuel gauge began to give a faulty reading. It climes as the car gets hot. However, I fixed this problem on the race car by going to a fuel cell. IMO, C5s are a tremendous value for the dollar.
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A lot of GM products have this problem. Most of the time it is caused by the "brushes" that rub against the fuel level sensor in the tank on the fuel pump. I had this same problem on my 06 TB SS. I wish I could draw a picture of it lol but what happens is that when the edges of the two "brushes" ware down they become to short to rub up against the sensor. GM/and AC delco sell the bruses and the pigtail seprate so you do not have to replace the pump. ![Angel](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_angel.gif)
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I have a 2000 frc that just turned over to 100K miles and i DD it in the summer.
Last season I did Cam only and never had a single issue with the car, ran 12.40s on drage radials.
This year I added heads/full exhaust.
Been having some electrical issues. One was during tuning the car. The PCM didnt like something and I lost ALL power. Ended up putting a new battery in it and it fired up (starter kept cranking etc). Turned out it wasnt the battery since I put the old one back in afterwards.
I ended up changing the positive terminal and the starter solinoid after melting a battery terminal. My starter was sticking when cold and I think may have overheated the positive wire.
I never really figured the issue out but that was 2 months ago. Only issue I seem to be having is a random SLOW CRANK. One day I will get in the car and it will crank awesome, the next it will crank like a dead battery (even with a new battery)
I do however love the car and been loving it since day one. I get looks everywhere and tons of compliments. The car handles amazing and is super fun to drive.
Jay
Last season I did Cam only and never had a single issue with the car, ran 12.40s on drage radials.
This year I added heads/full exhaust.
Been having some electrical issues. One was during tuning the car. The PCM didnt like something and I lost ALL power. Ended up putting a new battery in it and it fired up (starter kept cranking etc). Turned out it wasnt the battery since I put the old one back in afterwards.
I ended up changing the positive terminal and the starter solinoid after melting a battery terminal. My starter was sticking when cold and I think may have overheated the positive wire.
I never really figured the issue out but that was 2 months ago. Only issue I seem to be having is a random SLOW CRANK. One day I will get in the car and it will crank awesome, the next it will crank like a dead battery (even with a new battery)
I do however love the car and been loving it since day one. I get looks everywhere and tons of compliments. The car handles amazing and is super fun to drive.
Jay
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I too have had 2 c5s. For a total of 10 years. These cars a rocks. I mod them and drive them hard. Take care of them and they look brand new in and out. Their light and beat cars that have more horsepower.
Only electrical things, some very few cars might have the injector wiring harness rubbing thru against the rear of the head, a few cars had the ddoor harness stretch out. There's a few grounds, just keep em clean. Personally I never had any of these problems, only problem I had, was the intermittent no start. I took the ignition switch apart, cleaned it, like new. I could buy a c6z or whatever, but the c5 rocks!!!
Only electrical things, some very few cars might have the injector wiring harness rubbing thru against the rear of the head, a few cars had the ddoor harness stretch out. There's a few grounds, just keep em clean. Personally I never had any of these problems, only problem I had, was the intermittent no start. I took the ignition switch apart, cleaned it, like new. I could buy a c6z or whatever, but the c5 rocks!!!
Actually, recently on my Z I had some odd electrical issues. Charge faults, fans not kicking on, lights turning on by themselves and the battery was over charging and sometimes not charging at all... Turns out it was just a single ground that has some corrosion. I cleaned up all the contacts and haven't had any trouble since.
Most electrical problems are caused by corrosion. There are a few electronic components made with really weak solder points, which in 2001+ C5s are all easy to fix. The exception for all C5s is that the 2000 and older C5s have an ABS/TCS/AH module (The EBCM) that cannot be repaired. They suffer from the same shitty solder points on a relay as the 01+ C5s, except the 01+ has a redesigned module that can be very easily rebuilt.
Aside from that, finding electrical issues is easy and almost always a simple fix. The problem with C5s that make them seem like a nightmare is that there's LOTS more computers and LOTS more sensors than an F-body. There's a speed sensor on every wheel, there's steering wheel position sensor, at least 4 interior sensors, a control module for each door, the seats, the HVAC, brake system, radio (Yes the radio too), and other **** I can't even think of right now.
So there's more that CAN go wrong and more **** to replace if something does go wrong.
But the truth is that they're very good cars. I've had 2 C5s and my dad has a C5 too. Both of my Z06s were and still are stellar cars with no real issues other than my current reverse lock-out solenoid is hit-n-miss. My dad's C5 has a bad actuator in his HVAC but nothing that matters because his car is a Vert. He doesn't use the A/C much.
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I have 2 c5Z06's and I had one small electrical issue but it wasn't the car's fault. I took it to the track and wheel hopped like a SOB and a couple of days later the drivers side window wouldn't work...pulled off door panel, checked fuses, etc etc. Turned out to be the power relay had come unplugged at the door jam. Other then that, I haven't had an electrical issue with them. Of course, it depends on the care of the car, miles, and how old it is. They are nowhere near as bad as f-body's Ill say that. My window motors don't burn out all the time, headlight motors work fine, etc.