00 Z28 gauges going crazy
Thread Starter
Staging Lane
Joined: Sep 2015
Posts: 51
Likes: 0
From: Hugoton,KS
00 Z28 gauges going crazy My 00 has been having this issue since I bought it a couple weeks ago. It wasn't that bad at first, the Speedo was jumping around about 5mph going 70 but if I went under 66 or so it wouldn't do It and also the ASR off light comes on.. Around town driving normal it won't do it at all unless I got wot and then it'll start doing it. Now today as I was on the highway the Speedo started fluctuating really bad and then a couple minutes later my "Service Engine" light came on, not the SES, and then the tachometer went to zero and then the coolant temp, fuel, and a little bit of the oil pressure gauge (by a little bit I mean it would go dead but come back up faster the the others) went dead. The car kept running thought like normal and then randomly the gauges would return to normal for a little while. What's weird is that as soon as I slow down to about 50 or so it'll work like normal and won't do that as long as I am in town and keep it under highway speeds. What does this sound like to you guys? Bad ground? Bad pcm? There's no codes but occasionally I'll get p0175. Its also had trouble downshifting to the right gear, cruise doesn't work, and it won't shift into 2nd under normal throttle until it hits 15 mph which I feel is too much?
https://youtu.be/8S2QNUSTllA
I got it on video so you guys can see what I'm talking about.
https://youtu.be/8S2QNUSTllA
I got it on video so you guys can see what I'm talking about.
Teching In
Joined: May 2015
Posts: 37
Likes: 0
From: SA TX
Are you going into limp mode? If so, I'd suspect the coolant temperature sensor (or its wiring) as being the culprit. That sensor's located on the driver's side head, up above your number one cylinder. Start the car, and have someone jiggle the attached wiring to see if you can replicate the symptoms.
It could be an electrical issue, like you considered in your post. Have you checked your grounds yet? Is your alternator giving you enough power? What's the condition of your battery? All of these issues could be causing what you're seeing... Good luck chasing down the gremlin.
It could be an electrical issue, like you considered in your post. Have you checked your grounds yet? Is your alternator giving you enough power? What's the condition of your battery? All of these issues could be causing what you're seeing... Good luck chasing down the gremlin.
Thread Starter
Staging Lane
Joined: Sep 2015
Posts: 51
Likes: 0
From: Hugoton,KS
Yeah I tried that before is wiggle the wires around and nothing. I'm thinking its an electrical problem.. but I've just had bad luck with the car. Yesterday the water pump gave out and made a mess of coolant everywhere. What I noticed when it happened tho is the voltage gauge went pretty low and then as I sped up it when up again. Could that of been because of the coolant leaking on it? And also now it has no fuel pressure. 0 psi with KOEO. Voltage gauge in the car shows its around 9-10 volts but it still cranks fine? Lights and everything work as well, not dim. Just won't fire. Also fuel gauge shows E but it had 3/4 when I parked it last.
So I looked for the grounds and most seemed fine. The one going from behind the alternator to ground was not tight so I tightned it but the one that has me thinking is the 3 that are behind the drivers side head. I could move them a little bit forward and around. The bolt is maybe 1/8in from being tight.
So I looked for the grounds and most seemed fine. The one going from behind the alternator to ground was not tight so I tightned it but the one that has me thinking is the 3 that are behind the drivers side head. I could move them a little bit forward and around. The bolt is maybe 1/8in from being tight.
Teching In
Joined: May 2015
Posts: 37
Likes: 0
From: SA TX
Have you tested your alternator and battery? It sounds like a charging issue...
Did the previous owner mention having similar issues when you purchased the car? Do you have any aftermarket electrical draws?
Did the previous owner mention having similar issues when you purchased the car? Do you have any aftermarket electrical draws?
Thread Starter
Staging Lane
Joined: Sep 2015
Posts: 51
Likes: 0
From: Hugoton,KS
I haven't gotten them checked yet but I 'll do that if I can get my hands on a voltmeter. For the past few days I've noticed the gauge only shows right above 13v while driving around which of I'm correct that's the output of the alternator? Which i know should be around 14.7v.
No the only thing he said was it has trouble starting which it still did when I got it. I'd usually have to crank it twice. The first time I'd try it will just crank and crank. Second time it would start right away. When it's warm out during the day itd start on the first try. Sometimes and more I noticed when it was colder like during the early mornings, it would take like 7 times to start it. It'd just crank and after a couple trys, there would be a little pop from the exhaust.
No I don't have nothing that would draw more current.
No the only thing he said was it has trouble starting which it still did when I got it. I'd usually have to crank it twice. The first time I'd try it will just crank and crank. Second time it would start right away. When it's warm out during the day itd start on the first try. Sometimes and more I noticed when it was colder like during the early mornings, it would take like 7 times to start it. It'd just crank and after a couple trys, there would be a little pop from the exhaust.
No I don't have nothing that would draw more current.
