Electrical issues - ZR-1 Net Registry Forums

Billy Mild · 08-07-2014

I just recently bought a C4 ZR1. I bought it almost site unseen. I was told everything worked, car didn't leak any fluids, and it was a good runner.

The issues with the car were it needed tires, and some minor interior work.

Well so far it has been alright. I did change the oil, trans fluid, and rear end fluid. In an attempt to get the radio working I unhooked the negative battery cable for a few hours in hopes of clearing a code. That didn't work, but on my drive to work the other day I noticed something. The car would almost stall out for a split second. The lights would get a little dim, AC would stop running for a split second, then continue on no problem. It would be so fast I couldn't even get it on video.

The LTPWS light was very dimmly lit as well. Then the Service ABS light came on half way through the drive. The next drive the Service ABS light did not come on.

Could this just be bad grounds or something more serious?

WARP TEN · 08-07-2014

it is fairly common for ZR-1s to have corroded ground connection issues, especially the connections at the back of the engine. Also an old and weak battery may cause this sort of gremlin. Search the forum and you will find a lot of info on the subject of ground problems and electrical gremlins. -Bob

Billy Mild · 08-18-2014

I cleaned the main ground points in the interior. 2 up front by the speaker pods and then 2 back around the loop by the rear hatch.

I haven't driven the car yet, but are there any other grounds that I could get to without taking the intake manifold off?

mike100 · 08-19-2014

Sometimes the aftermarket chips program both fans to come on at the same time. This does cause my gauges to dim so I reprogrammed them to come on 1 degree (celcius) apart.

Also, C4's get wonky right before you lose a battery.

USAZR1 · 08-19-2014

Quote:

Originally Posted by mike100

Also, C4's get wonky right before you lose a battery.

Yep. Been there,done that.

Billy Mild · 08-19-2014

Quote:

Originally Posted by USAZR1

Yep. Been there,done that.

Should I have the battery tested? It is an interstate battery.

I left the car on the battery tender all last night. It fired right up today and seemed to run fine, but I still noticed some of the LCD screen dimming. Also I had the car alarm going off after I got inside the office today. That was exciting.

I'm trying to get a video of it when this happens. The idle doesn't change, but the volt meter goes up and down a little bit when the turn signal is on. That points to some sort of electrical issue. I would like to have all my grounds clean and tight. Maybe it is the battery.

USAZR1 · 08-19-2014

Quote:

Originally Posted by Billy Mild

Should I have the battery tested? It is an interstate battery.

I left the car on the battery tender all last night. It fired right up today and seemed to run fine, but I still noticed some of the LCD screen dimming. Also I had the car alarm going off after I got inside the office today. That was exciting.

I'm trying to get a video of it when this happens. The idle doesn't change, but the volt meter goes up and down a little bit when the turn signal is on. That points to some sort of electrical issue. I would like to have all my grounds clean and tight. Maybe it is the battery.

I would have the battery load-tested before you start chasing bad grounds. Your symptoms do sound like the battery is going south.

ghlkal · 08-19-2014

I agree that you should check your battery first.

Quote:

Originally Posted by Billy Mild

I haven't driven the car yet, but are there any other grounds that I could get to without taking the intake manifold off?

Most of us have discovered that the two grounding points on the back of block near the bellhousing are critical. Cleaning up those grounds seems important. Unfortunately, I'm not sure if you can get to them with the plenum in place. I cleaned mine up when I had the plenum off.

Billy Mild · 08-19-2014

ZR1 idling gauges dim: http://youtu.be/aabq_eOLpd4

There is a video of what is going on. My ABS light hasn't come since I cleaned all the interior grounds. So at least there is a little difference.

I can get my battery tested tomorrow.

mike100 · 08-20-2014

thanks for the video...that wasn't exactly what I was expecting. I would say a gauge cluster ground or voltage regulator issue is the problem.

08-07-2014	#1
Billy Mild Join Date: Aug 2014 Location: Kansas City, MO Posts: 838	Electrical issues I just recently bought a C4 ZR1. I bought it almost site unseen. I was told everything worked, car didn't leak any fluids, and it was a good runner. The issues with the car were it needed tires, and some minor interior work. Well so far it has been alright. I did change the oil, trans fluid, and rear end fluid. In an attempt to get the radio working I unhooked the negative battery cable for a few hours in hopes of clearing a code. That didn't work, but on my drive to work the other day I noticed something. The car would almost stall out for a split second. The lights would get a little dim, AC would stop running for a split second, then continue on no problem. It would be so fast I couldn't even get it on video. The LTPWS light was very dimmly lit as well. Then the Service ABS light came on half way through the drive. The next drive the Service ABS light did not come on. Could this just be bad grounds or something more serious?

08-07-2014	#2
WARP TEN Join Date: Apr 2007 Location: Lake Bluff, IL Posts: 2,038	Re: Electrical issues it is fairly common for ZR-1s to have corroded ground connection issues, especially the connections at the back of the engine. Also an old and weak battery may cause this sort of gremlin. Search the forum and you will find a lot of info on the subject of ground problems and electrical gremlins. -Bob __________________ 2016 Long Beach Red Z06 #10281 "POPS Z" 1995 Polo Green #409 "WARP TEN"--Haibeck 350/510 package, 4.10s, Hurst, Stock Exhaust with QTP Cutouts --Sold but still running strong 1993 Quasar Blue #161 "HIL KING" --Sold but still running strong, now with more than 120,000 miles 1967 Marlboro Maroon/Saddle Corvette Coupe 300 hp/4-spd --Sold a long time ago ZR-1 Net Registry Founding Member #95 NCM Lifetime Member Favorite Quote--Attributed to Mickey Thompson: "Too Much Horsepower is Almost Enough"

08-18-2014	#3
Billy Mild Join Date: Aug 2014 Location: Kansas City, MO Posts: 838	Re: Electrical issues I cleaned the main ground points in the interior. 2 up front by the speaker pods and then 2 back around the loop by the rear hatch. I haven't driven the car yet, but are there any other grounds that I could get to without taking the intake manifold off?

08-19-2014	#4
mike100 Join Date: Feb 2011 Location: San Marcos CA Posts: 1,802	Re: Electrical issues Sometimes the aftermarket chips program both fans to come on at the same time. This does cause my gauges to dim so I reprogrammed them to come on 1 degree (celcius) apart. Also, C4's get wonky right before you lose a battery.

08-19-2014	#9
Billy Mild Join Date: Aug 2014 Location: Kansas City, MO Posts: 838	Re: Electrical issues ZR1 idling gauges dim: http://youtu.be/aabq_eOLpd4 There is a video of what is going on. My ABS light hasn't come since I cleaned all the interior grounds. So at least there is a little difference. I can get my battery tested tomorrow.

08-20-2014	#10
mike100 Join Date: Feb 2011 Location: San Marcos CA Posts: 1,802	Re: Electrical issues thanks for the video...that wasn't exactly what I was expecting. I would say a gauge cluster ground or voltage regulator issue is the problem.