Need help with Fluctuating Temp Gauge LT1 Roadmaster Wagon?
93 Roadmaster Estate Wagon, 70,000 miles. LT1 350
New Cap, Thermostat, and full on coolant. Fan kicks on, not loose or bad fan clutch. No white smoke.
Started on a long trip from STL, MO to CA.
Mostly happens when starting from cold. Will go into Red Zone and then before I can pull over or count to 10-20 it will fall back down to normal range. However on a long drive it will sometimes do it while driving, could be up hill or down, so load or air flow doesn’t seem to be the problem.
Will not heat up at idle, but at cruise RPM of about 1800RPM.
Noticed recently that the oil pressure indicates high oil pressure early on and changes to normal with the temp gauge.
Found a posting about the exact same problem for this year, but no response. Anyone else know of this and can help?
Thanks in advance.
roadmaster shocks
May 25th, 2010 at 1:09 pm
strutmasters.com
With new parts, full on coolant, and fan working properly it should be OK.
This problem sounds like the thermostat is sticking. It is the only thing I can think that would cause it to heat up and then correct itself like that. It is possible to get a defective part (thermostat), or wrong thermostat.
It is normal for oil pressure to be higher until the engine warms to normal temperature.
May 26th, 2010 at 4:31 am
roadmaster shocks
Are you sure it is actually heating. Could be a defective temp. sensor. Was it doing this before you changed the thermostat? Did someone possibly put the thermostat in upside down ? Do you have the correct pressure cap for your car ?
Just some thoughts