basspro1886
TYF Newbie
- Joined
- Nov 9, 2012
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I have an 99 Tahoe with the 5.7 engine. I just had the Tahoe worked on by a local mechanic and he had replaced and flushed the coolant and thermostat. He performed other work but nothing to do with the coolant. When I got the truck back, I noticed that the temp gauge was fluctuating more than normal. It would go up to 240 and then back down to 195. I returned the truck and told him what it was doing. He replaced the thermostat again with a 195 thermostat and then pressure checked the system. The system was solid and then installed his scanner and drove the vehicle. He stated that the engine is running at 195 to 200 degrees. With this said he told me that the sending unit is probably the issue. So over the next few days I had noticed that the gauge is starting to creep up to 260 and then it pegged all the way over past 260 and would not move. So this morning I replaced the sending unit. Refilled the coolant and drove. This time the gauge is still over to the 260 mark, but is not pegged. I checked the wires and the connection and everything seems to look okay. I went back to the mechanic and his reply was your cluster is most likely going bad. Is there any other troubleshooting ideas that can help before I go and get a new cluster. I have the manual but it is very limited on wiring.