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Coolant temp

2K views 4 replies 3 participants last post by  calgobble 
#1 ·
So some back story first,

I had a crack in my radiator so I ended up replacing that with one from XDP as well I replaced the t-stats from Mishimoto, the upper/lower hoses, and coolant reservoir from my local parts store. After I burped the coolant system I am still getting a low coolant message, coolant is not low just FYI. I also notice that the temperature sometimes rises to just below 210 and then drops back down to right around 185-190. The temp will rise when I get on the throttle and then will decrease if I left off or sometimes it will do it while still in throttle. I don’t remember the truck sound this before I replaced everything the reservoir.


Could the coolant level sensor be faulty in the new reservoir? Could the coolant temp sensor going bad?


Thanks for reading and any insight.
 
#2 ·
Having an LLY, my 12 year old aux radiator sprang a leak and I had to put in a new one (LLYs overheat, you know). After bleeding and burping and burping and burping, I had more temperature fluctuation than I had before. I was wondering if the new aux radiator was dumping such cold water into the system that things were a little wacky when the thermostats opened. Then somewhere along on a long drive it seems to have gone back to normal. (With the aux radiator, the temps still drop well below 190*F when coasting, kind of like on a cold day.)

While I could be tempted to chastise you for not bleeding and burping it properly, I would have to chastise myself for the same problem! But I think we did it right and I think it just takes awhile for those air pockets to be purged.

One thing I didn't do this time that I normally do when bleeding . . . so maybe this is the secret . . . is I usually bleed not only from the bleeder, but also from the heater hose which is a little higher up. Maybe it gets more out. Maybe.
 
#3 ·
(I can't edit, so I'll add here) It seems likely that either the coolant level sensor is bad, or the connector is bad, or the connection is bad, or the wire got damaged while you were working on it. You should be able to test the sensor with a VOM, and the wiring, but sorry, I haven't had to do this so I don't know the details (like sensor open = low and closed = ok, or visa versa).
 
#4 ·
I'm pretty sure these things don't have the best purging system.
After my head swap, I was adding coolant for like a week. A little nerve racking after such a big job to say the least.

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