Early Caravan no heat at idle

It is no secret. Number one they cant tell you what the problem is because it is just information on how to test the system with a diagnostic test scanner NEW VEHICLE. It is a TSB that was written back in 1994 to explain to the technicians how to test out the components. Since you only have a problem of lack of heat at idle this TSB would not pertain to your vehicle anyhow. Go back to basics. lack of heat at idle, heater core possibly stopped up??? Or a fault code 17 Thermostat stuck open? If you have hot coolant going into the firewall (heater core) and cool/cold coming out your heater core is stopped up!!! If you have no hot coolant going into heater core find out why!!! thermostat? Low on coolant??? Forget the TSB it doesn't pertain to your vehicle. Maybe that's why they would help you out?

Glenn Beasley Chrysler Tech

Thanks for the reply Glenn. Beg to differ. I saw the monitor at the dealer. Top line DSB 24-05-94. No heat at idle. Gave a part number that may cause the problem. Unfortunately service rep wouldn't even give me that number. As far as the dealer scan, I had one done once, didn't find a thing. The heater core was flushed out. New thermostat installed. Started it and as it warmed up, it does open. New rad installed. New water pump. New bypass hose. The part next to the in hose to the heater core, called I think an accuator ( probably mispelled) opens and closes when I move the heater controls on the dash. Not much else left to check or replace. Also lots of coolant. Has me scratching my head. Not much else to check or replace. IMHO I think the dam thing just cools to well. Even in the summer, the electric fan for the rad hardly ever operates. As far as the dealer not wanting to give me a copy of the DSB. Told me it was a derective from their head office at Chrysler. Not very goog customer PR as far as I'm concerned. Even if the DSB didn't pertain to my vehicle it could have been at least a little useful to me at some level.

DS

I had a similar problem with my 82-3-4??? Voyager. The year does not really matter. It was one of the first ones built. The FSM wiring diagram is not exactly the same as the wiring in this van - and this van has original wiring. I suppose they did a "few" things in the actual first production....... (I found the original manifest stating what was put into the van at the factory-- interesting but I digress)..

With the "original" heater core, the heat was minuscule. I replaced the "original" heater core with an after market one. Vive la difference. Lots of HOT air now. I actually have to turn the heat down... (and I just run the engine in the drive way as I have not put plates on it in the least few months...)

The original heater core was like an old-time "classic design" rad core: top and bottom tanks with "tubes" between. The heater core tubes in my Voyager were few and "tiny" Not much flow through the core I suppose (!) The after market core is of "honeycomb design". While it has only been -12C at the coldest here in Winnipeg, this new unit is throwing out a LOT more heat than the older design....

Just my experience. YMMV.

Ken

I wondered about this. I have a 94 GC, and there is precious little heat coming out the vent. Supposedly everything is "fine".

Fortunately, being on the West Coast, it never really gets that cold here - not like when I lived in Saskatchewan!

I do have an ongoing maintenance program for the van, so perhaps I will have the heater core replaced.

Just put of curiousity, how huch was the part, and what was the labour cost to do this job???

Thanks

Thanks Ken. Great help. Yes, I would like to know where you purchased the replacement heater core as well. I know when I replaced the original rad the aftermarket one was much better quality. Sounds like the heater core is the same deal. The DSB said low or no heat at idle is normal. Yeah right, normal for a poorly designed heater system, maybe. thanks for the reply and info. Errol

Thanks Ken. Great help. Yes, I would like to know where you purchased the replacement heater core as well. I know when I replaced the original rad the aftermarket one was much better quality. Sounds like the heater core is the same deal. The DSB said low or no heat at idle is normal. Yeah right, normal for a poorly designed heater system, maybe. thanks for the reply and info. Errol

There is no such a thing as a "DSB". The term is "TSB", Technical Service Bulletin.

Pardon my rusty mechanical knowledge, but aren't there doors in the ventilation system that redirect airflow through the heater core or away from it? Perhaps they're not moving properly?

I cannot remember what I paid on e-bay. To make sure I had the unit checked out (for leaks and flow) before I installed it. It cost me my time..... I did the work myself.