Heater core?

**Brich** · 07-10-2015

Hey guys - I had posted a while back, and a lot of you helped me out, about my overheating problem with my 2005 GTP and the sloshing behind the dashboard. Now I am having some new, and most likely related issues. Was hoping for any advice or guidance ..

Sloshing sound is gone since I pulled off the heater core hoses and filled it. Thought I had heat after that, but it was temporary. I still have no heat, and when I put my defroster on the windshield I notice a smokey kind of condensation blowing across the windshield. So I am curious, what does all this imply?

Also not 100 positive but sometimes I feel like it may still be running a bit hot (and curious if it is all tied together). One of you mentioned to me that the middle line is around 195, one tick up is 200, 3 ticks is 212 and riht before the redline is 221. Mine appears to sometimes creep up to the second tick past middle (assuming 205 or so) and then I think the fan kicks on because once it gets there is usually comes down to around the middle. Sometimes it just stays one tick above (205). Maybe this is all normal, but after having the overheating problem I am paranoid and watch that gauge all the time, whereas I never looked at it before in years. So maybe its just me. Sometimes I smell antifreeze, but that could be all the antifreeze that spilled all over my motor burning off. It left a ton of stains. I would love to use my A/C since its summer, but I am too worried to overheat again.

thanks for listening and appreciate any advice.

- brian

**bandook** · 07-10-2015

The fog on the windshield could possibility indicate you have a small leak in your heater core. If its on the outside of the window and the ac is blowing cold that's just normal condensation.

The fans kick on pretty high, around 212-215 I think. If the temps drop after fans come on I wouldn't worry about it that much. If you have high mile age and haven't done a water pump I probably would. Its not a hard job and cheap insurance.

**J57ltr** · 07-10-2015

I was incorrect in the information I gave and the temps are slightly higher than that. it's more like 205. My fans do not kick on until the engine temp reaches about 217-219 using both a 04' PCM and an 05' PCM that temp is right about a couple of ticks above the half way point. I have never had the high speed fans come on they only come on low at the 217-219 area. If I have the AC on, which is all the time now, the temp usually never gets over 206. I also have a 180* T-Stat. when I had the 195* it was always between 205-210. But like Bandook said you may have a leak. Does it have that maple syrup smell? It's summer disconnect the hoses and plug them together, worry about it in the winter.

Jeff

**bandook** · 07-10-2015

And I'm not sure the purpose of a 180° stat in these cars. I had one in my car for awhile and the temps were the same. Once the engine warms in the summer, the only thing that drops it is the fans. And in winter it would probably just mean it will take longer to get the car warm. I reprogrammed my fans 15 degrees lower and now it runs cooler of course. If someone can explain the point of a cooler stat on stock pcm I'd be interested to hear.

**Scottydoggs** · 07-10-2015

cooler t stat is old school modding, its not even relevant in a 3800 where the pcm runs the engine. all GM cars want to run @ 210 degrees.

that being said lol my fans are lowered to 180, and im running a 195 t stat still. car runs around 200 or so tops in traffic, lower on the highway of course.

**J57ltr** · 07-10-2015

I live down here in hell where it is 95 at night and the 180* stat seems to keep everything cooler. I don't have an external trans cooler so my trans temps were in the 220-230 range all the time. With the AC on, which like I said is all the time my engine temp never gets over 206 it actually averages 194. We don't have this thing you call "winter" down here so it will warm up just as fast as it does during the rest of the year. If I had a tuner I would kick the fans on at a little lower temperature and in my case I don't have any issues with not burning off condensate in the engine as I drive at least 60 miles a day for about 2 hours total. I am sure there is some preset speed at which the fans turn off even with the AC on but I only have about 12 miles of my daily trip where I am over 60 mph most of the time. My IAT's get into the 150's with a stock airbox and with the cone filter although it was a little better with the stock airbox. I plan on changing that around a little, but for now I am just happy the thing runs correctly. I would agree with you if I lived in an area where the temperatures are cooler, but down here we have dense air (30.00 baro) and high humidity and high temps so I did the 180* as a stopgap until I can do some other things to keep the temps in check.

Give me time I ave only had the car for not even 3 months yet.

Jeff

**Scottydoggs** · 07-10-2015

trans cooler asap, by pass the rad run it solo.

you can get the fans turned down. but like you said, the temps can creep back up to 210 if in traffic still.

your engine temps are in the normal range, the tranny is way to hot.

**J57ltr** · 07-10-2015

I know I have seen this a lot where everyone bypasses the factory one, but I have always added them after the factory one in series and not had any issues. Is it that big of a deal?

Jeff

**Scottydoggs** · 07-10-2015

the stock cooler is in the rad, its cooler is now 200 degrees, see my point now? lol

sure a new cooler in line will lower the temps, but with temps like your seeing solo is what id do. and cause you live in tx and its hot year round.

if you lived up north where we get a winter, in line is best.

**Brich** · 07-10-2015

Originally Posted by J57ltr

I was incorrect in the information I gave and the temps are slightly higher than that. it's more like 205. My fans do not kick on until the engine temp reaches about 217-219 using both a 04' PCM and an 05' PCM that temp is right about a couple of ticks above the half way point. I have never had the high speed fans come on they only come on low at the 217-219 area. If I have the AC on, which is all the time now, the temp usually never gets over 206. I also have a 180* T-Stat. when I had the 195* it was always between 205-210. But like Bandook said you may have a leak. Does it have that maple syrup smell? It's summer disconnect the hoses and plug them together, worry about it in the winter.

Jeff

I wish it smelled like maple syrup. I love syrup. It doesn't that I have noticed though. I may trade the old girl in on a truck November, so I can live with no heat until then. Although I am pretty uptight about not having all my stuff working. As much as I love that car (first new car I ever bought) it isn't holding up well for me lately and I have been pretty diligent about maintaining it ... Except for that oversight of not changing the coolant which led to all of this inevitably. I may look into how big a job it is to replace the heater core, and I would of course do the water pump too at the time. If/ when I sell it I want to know it is in decent shape for the buyer.

**Brich** · 07-10-2015

Originally Posted by ScottyDoggs

cooler t stat is old school modding, its not even relevant in a 3800 where the pcm runs the engine. all GM cars want to run @ 210 degrees.

that being said lol my fans are lowered to 180, and im running a 195 t stat still. car runs around 200 or so tops in traffic, lower on the highway of course.

Cool ... How does one lower the fans???

**Brich** · 07-10-2015

Jeff .. I have some buddies in Tomball. Or they used to live they maybe ... Yeah it's hot as hell I hear. They were from NJ and couldn't deal with it.

**J57ltr** · 07-10-2015

Lol, it's smoking for sure. The only place where you see temps in the low 90's and feels like temp of 100, with 48% humidity. The concrete actually causes the city to be a few degrees warmer than surrounding areas most of the time. When we camp we take air conditioners for our tents, and don't dare leave without a canopy if you don't know where your camping, you'll burn alive. I travel a lot and I would take this over snow any day. I have been involved in 3 accidents and totaled one rental car (with only 5k miles). Luckily 1 totally wasn't my fault, one was black ice on a blind corner on a mountain, and the other I just got stuck in a snow drift... Well if I count that as an accident I've gotten stuck 3 times all with hilarious results. So I'm not a good driver anyway we won't go into the others I guess. Sunny months if I setup a project I'm lucky enough to be able to take my car into our shop and turn on the AC. I had to make an area in the garage that was AC'd or it's just unbearable.

Jeff

**Scottydoggs** · 07-10-2015

Originally Posted by Brich

Cool ... How does one lower the fans???

you need a tuner program to change it in the pcm. where in NJ are ya? i got a tuner. im up in hackensack.

**bandook** · 07-10-2015

Yeah its a running joke up here in the polar regions that you southerners haven't a clue how to operate anything on wheels in more than 1/8" of the white stuff. 1/4" and the whole city shuts down lol. Well, the rust inducing chemicals help us get through a winter, but I don't mind driving on snow. The worst part is when it melts then freezes and leaves huge ruts and icy potholes.

**J57ltr** · 07-10-2015

It's like driving on cobblestones. I've been doing this for over 15 years so I do end up with a lot of time behind the wheel on snow and ice. Even made it through a couple of blizzards, and the places I go end up being in the middle of nowhere. I've had to rent a hunting cabin and drive 20 miles to a plant and 45 miles through mountains in WV to the nearest grocery store. Lol. It still sucks to drive in it. I even get up into Canada a lot and it's never in the summer it seems.

Brich,

If its not smelling of Antifreeze, and you are running the AC chances are you just have a plugged up condensor drain. If it was coolant you would smell it for sure.

**Brich** · 07-10-2015

Originally Posted by ScottyDoggs

you need a tuner program to change it in the pcm. where in NJ are ya? i got a tuner. im up in hackensack.

I'm in Hillsborough... So a decent trip south of you, but I do occasionally get up around Saddle River to fish. So if I know I am going, I will try to get hold of you before and see if you're around.

**Brich** · 07-10-2015

I meant to unplug that last time but I think once I fixed the sloshing via the heater core method I forgot about it. I may hit it tonight ...one less thing. When I saw the smoke I actually had the heat on and not the AC. I shut it down quickly so I will run it tomorrow with it blasting for a bit and see what's what.