Tach and Speedometer acting strange
stuarnold
08-28-2005, 02:33 PM
I have searched the forums for an answer to this problem without finding anything specific that will fix the issue.
One day I was driving along (1994 K-1500 5.7) and all the sudden a lot of electrical noise began coming through the stereo system. I also noticed at that point that both the speedometer and tachometer were acting strange. The tach was showing that I was red lined but the engine rpm's were fine. I let off the gas and the tach lowered some but still read way too high. Pulled off the road and turned the truck off for a few seconds then restarted and everything seemed fine. It stayed this way for a while then started doing the same thing again. Again I turned it off and restarted and everything was fine.
The other day I went to use the truck and it would not start. After a couple of tries it finally did. Today I went to use it and something (most likely the starter solenoid) clicked a few times but it would not start. Tried again and get nothing from the starter. The instrument panel lights up just fine, power windows operate fine, and the battery is showing good power.
I would normally think it was the starter that had gone bad but since I had the other problems (tech, speedometer and electrical noise) I am beginning to think it is something electrical.
From reading post in the forums I am going to have the ignition module tested this week. The only other suggestion I found was to replace the ignition switch. I'd rather leave this as a last resort since it is going to be a pain to change.
Has anyone experienced this problem? Especially having their tach and speedometer go crazy?
Thanks,
Stuart
One day I was driving along (1994 K-1500 5.7) and all the sudden a lot of electrical noise began coming through the stereo system. I also noticed at that point that both the speedometer and tachometer were acting strange. The tach was showing that I was red lined but the engine rpm's were fine. I let off the gas and the tach lowered some but still read way too high. Pulled off the road and turned the truck off for a few seconds then restarted and everything seemed fine. It stayed this way for a while then started doing the same thing again. Again I turned it off and restarted and everything was fine.
The other day I went to use the truck and it would not start. After a couple of tries it finally did. Today I went to use it and something (most likely the starter solenoid) clicked a few times but it would not start. Tried again and get nothing from the starter. The instrument panel lights up just fine, power windows operate fine, and the battery is showing good power.
I would normally think it was the starter that had gone bad but since I had the other problems (tech, speedometer and electrical noise) I am beginning to think it is something electrical.
From reading post in the forums I am going to have the ignition module tested this week. The only other suggestion I found was to replace the ignition switch. I'd rather leave this as a last resort since it is going to be a pain to change.
Has anyone experienced this problem? Especially having their tach and speedometer go crazy?
Thanks,
Stuart
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