1998 Dodge Caravan Heat

ozzman71

First, what causes my caravan to not want to start in cold weather? It will start but it takes a while to get it started. When it finally does start it back fires.

Second, the heat only works when the I'm pushing the gas pedal. When I'm driving the heat works for a minute or so and then gets cold. I turn it off and wait a few minutes and it does same thing. The heat won't work at all if it's just idling.

Any help would be appreciated. Thank you.

xwesx

The intermittent heat sounds like a result of low fluid level, or an air pocket in the system.

The hard starting may be caused by low fuel pressure and/or "flooding." When you start the van, try turning the ignition to the "on" position for a couple of seconds before attempting to start it. Does it start easier? You should be able to hear the quiet "whirring" sound of the fuel pump priming the system for a second or two when you first put the key in the "on" position.

FYI, backfires are caused by unburnt fuel in the exhaust system.

ozzman71

Thanks for giving a quick reply. I'll try that when I'm starting next time. It only does it when it sit for a while. I'll let you know what happens.

What cause an air pocket in the system?

xwesx

The air pocket in the coolant, if not caused by low fluid level and not an artifact of recent work (such as thermostat replacement, fluid replacement, etc), is most often due to a head gasket leak (causing combustion gases to be forced into the coolant channels). But, I have not heard many instances of failed HGs on these vans, so it is more than likely something that is easily resolved.

ozzman71

I tried what you said and it started a little better. It still didn't want to start but it didn't take as long to get started. Thanks for your help.

colloquor

The 3.3L V6 has a propensity to develop head gasket leaks, especially on the front bank of cylinders. The head gasket leak is generally on the flywheel end of the engine - right-side while viewing from the front of the engine bay.

I had this problem on my '94 Grand Caravan ES, and we had no heat! As soon as I tore it down and replaced the head gasket (actually I replaced both), we once again had normal heater operation.

shipo

"The 3.3L V6 has a propensity to develop head gasket leaks, especially on the front bank of cylinders."

Really? I participate on a number of minivan related boards (and am even a moderator on one), and for the Gen 3 and later vans (i.e. 1996 and later), I've never even once heard of folks having head gasket issues (errr, unless someone seriously overheated the engine).

FWIW, my former 1998 had a slow loss of coolant that was engine up in the engine oil (not a good thing), and all of the sages opined that the problem was a head gasket leak. One week during the summer of 2007 I pulled the heads off and replaced the gaskets, and guess what, not only did I not find any place where the head gaskets had been compromised, but the leak continued at the same pace as before. The problem turned out to be a ten cent "O" ring in the timing chain cover (a problem that is occasionally reported).

Best regards,
Shipo

xwesx

I also have not heard of head gasket leaks in these engines, especially not "a propensity for" them. While I do not think it is the most probable cause, a head gasket leak can lead to air pockets in the coolant channels and cause overheating, loss of flow to the heater core, etc. It is always worth exploring this option as it is certainly possible for the gasket(s) to fail, especially if the fluid level does not appear low and there was no recent service activity that could have introduced air to the system.