1996 Jeep Grand Cherokee "car heater heats rev engine" Questions

...heated fine but heater wouldn't work. Cause? Air in the system. Run the engine with the cap off, rev the engine up and this will help purge the air. Fill as needed and keep check on it for a few

...rev engine higher for secound test, heatercore lines going into firewall are hot,still not much heat on high. Maybe vacum leak on controls? British columbia Canada There is air trapped in you cooling ...

...rev the engine a bunch Very likely your heater core is leaking and that's why the floor is wet. The reason you are having problems with the heat is that the coolant level has gotten lower than it is ...

...Heater Circuit Low - Engine ... https://www.engine-codes.com > p0037_jeep 'P0037 JEEP code tech notes ... The code means that there is a problem with the heater element circuit of the heated oxygen ...

...heater.  This can cause the shudder as engine adjustments are made.The O2 sensors have built in heating elements to rapidly heat the part and save fuel.  Its possible that engine is trying ...

...heater on (not defrost) and let it run for a while & top up rad as coolant goes down, to about an inch or 2 from top of rad. If you have electric rad fans, watch temperature gauge and around ...

...heater. The reason it comes good when you rev it is that it then gets enough heat to get into operating range. This sensor not working is making your ECM change you fuel and spark trim causing the ...

heater won't blow hot air until I rev up the engine a bunch or actually get on the road with it. I could let it just run idle for 30 minutes in the morning and it still won't blow heat until I rev it!

...heater will not work unless the vehicle is moving or unless I sit there and rev up the engine? Can you tell me what this might be? Hi it sounds like the water pump has failed hence no heat until you ...

...rev, for 5 seconds or so, every once in a while to make sure flow getting through heater core, and add coolant as necessary. See if that helps, as it may just be an airlock in system. If your cooling ...