Could the heater core be shot?

[slacktide_bitog]

2001 Firebird 3800 V6

The heat takes a long time to get hot, longer than it should.

When I did the water pump over the summer, I had a hard time draining the coolant and only got a small amount out at a time (listed capacity is over 11 qt, yet I could only drain 1-2 qt). Now that it's cold outside, I noticed the heat takes a long time to get hot.

For that reason, I'm starting to suspect a problem with the heater core.

I know the heater core is a very difficult, time-consuming job, and that the OEM heater core is still available.

 

[GSCJR]

Flush the cooling system and install a new genuine GM thermostat.

 

[Chris142]

Flush it out both ways with a garden hose. There's no real way to drain coolant from that engine due to a bad design.

All you can do is drain and fills.

 

[slacktide_bitog]

Flush the cooling system and install a new genuine GM thermostat.

I installed a GM OE thermostat 2 years ago and only put a few thousand miles since.

I tried to do a flush over the summer when I did the WP, using Blue Devil radiator flush, and there might still be some of it in the system due to not being able to drain the coolant.

Of course I'll fill it with 2-EHA free coolant (whatever Peak is calling it now), but if it's already time for another thermostat, I can do that, since it's easy.

 

[GSCJR]

Then just use the method @Chris142 suggested, right at the core; the stat should be okay then. Good luck!

 

[joekingcorvette]

I watched a video on LS1TECH and it's about a 2 hour job. It was for a 93-2002 Firebird/Trans Am but I am not sure if the 3800 is the same setup. It appears you have to remove a plastic panel under the glove box. Then remove the glove box and a few clips and wires and it's right there under a plastic cover that has to be removed. Of course you have to drain the antifreeze below the heater core level first. The job looks very doable for most handy man type of mechanics. Good luck!

 

[Nukeman7]

I suggest using a pressurized flush gun as shown in the SMA video below.

 

[samven]

You may just have air in the heater core. If you dont have a bleeder you could try parking on a steep hill with the front end up to get the radiator higher than the core or jack the front up. Run the motor with the cap loose on the first catch and keep an eye on the coolant level.

 

[Lubener]

2001 Firebird 3800 V6

The heat takes a long time to get hot, longer than it should.

When I did the water pump over the summer, I had a hard time draining the coolant and only got a small amount out at a time (listed capacity is over 11 qt, yet I could only drain 1-2 qt). Now that it's cold outside, I noticed the heat takes a long time to get hot.

For that reason, I'm starting to suspect a problem with the heater core.

I know the heater core is a very difficult, time-consuming job, and that the OEM heater core is still available.

Use a scan tool to verify the engine is running at the proper temperature. Then feel the heater hoses. They both should be very warm. If there is a big difference between them the core is restricted. Disconnect both heater hoses. Use a garden hose to "gently" flush out in both directions. Don't go full blast. You may have to purge the core of air afterward.

A couple years ago, I brought a heater core back to life by flushing it out. Couldn't believe the sediment which collected in the core.

 

[bullwinkle]

Back flushing the core seems to be the best way to get as much gunk out as possible. I would still ensure the thermostat is doing it’s job, even if you have to remove it & hang it in a pot of hot water to check it’s opening temperature.

 

[zzyzzx]

I installed a GM OE thermostat 2 years ago and only put a few thousand miles since.

 

[f355spider]

I suggest using a pressurized flush gun as shown in the SMA video below.

This is the way!
My story: 2001 BMW 540. About 5 years ago I started having an issue with no heat on the passenger side and very little heat on the drivers side (single heater core with left and right sides set up with individual controls for each side).

Took car to my independent BMW specialist and they connected up a garden hose and flushed all three passage ways on the heater core. There is a left and right side input and a single output. When they flushed the passenger side, some very obvious black gunk came out. They continued flushing both sides, as well as flushing in reverse.

After this the car was good for a year but come fall, same issue. So they did it again, this time first using a flush product chemical, then connecting up a low pressure electric pressure washer. Again, I was good for a year or two, then same problem.

I studied online and saw a similar video to this, and shared it with my BWW shop and the owner said he would simply buy one of those for his shop and for me to come back. This time I put a Lubro Moly cleaning product in the radiator before I left for the shop (its an hour away). When I got there, they let the car cool a bit, then hooked the tool to their garden hose and to my heater core and went at it. (It is clear in use, this flushing attachment creates more turbulence than you can get normally, or with a pressure washer.) Again flushing both sides of the core, and flushing it in reverse direction. Its been almost two years and I have good heat from both sides, and no further issues. I was ready to have the heater core replaced, but the entire dash has to come out, its a 3.5 to 4 hour job and my BMW tech did NOT want to do it.

 

[LDM]

I've flushed a few heaters cores over the years, sometimes it works great, sometimes not. It amazing how much junk you can get out of one with a good flush but sometimes they are totally ruined and just have to be replaced. Depending on the vehicle this can be a nightmare where you have to take the dash apart or a simple drop the cover under the dash and swap it out.

I have never had to replace the heater core on my 94 Z28 but from what I've seen it shouldn't require you to pull the dash as it has the cover under the dash and is accessible. Same on my brother's 97 K1500, just remove the heater core cover and replace.

A friend of mine's daughter had a bad heater core on her 04 Jeep Liberty. I tried flushing it but it didn't do anything to improve the heat. After looking up the process for the swap, you have to take the entire dash out of the vehicle as the heater core is right in the middle and not accessible any other way. I told her it was way too much work for me to be able to do as the estimated time just to get the dash out was 10-12 hours. I told her she was going to have to get used either driving without heat or get rid of it for something with working heat. She did the later.

 

[BMWTurboDzl]

This is the way!
My story: 2001 BMW 540. About 5 years ago I started having an issue with no heat on the passenger side and very little heat on the drivers side (single heater core with left and right sides set up with individual controls for each side).

Took car to my independent BMW specialist and they connected up a garden hose and flushed all three passage ways on the heater core. There is a left and right side input and a single output. When they flushed the passenger side, some very obvious black gunk came out. They continued flushing both sides, as well as flushing in reverse.

After this the car was good for a year but come fall, same issue. So they did it again, this time first using a flush product chemical, then connecting up a low pressure electric pressure washer. Again, I was good for a year or two, then same problem.

I studied online and saw a similar video to this, and shared it with my BWW shop and the owner said he would simply buy one of those for his shop and for me to come back. This time I put a Lubro Moly cleaning product in the radiator before I left for the shop (its an hour away). When I got there, they let the car cool a bit, then hooked the tool to their garden hose and to my heater core and went at it. (It is clear in use, this flushing attachment creates more turbulence than you can get normally, or with a pressure washer.) Again flushing both sides of the core, and flushing it in reverse direction. Its been almost two years and I have good heat from both sides, and no further issues. I was ready to have the heater core replaced, but the entire dash has to come out, its a 3.5 to 4 hour job and my BMW tech did NOT want to do it.

I just spent $500 on a heater core flush which didn't work. The shop wants $4,500 to replace the heater core. I haven't picked up the car but I have my reservations that they actually performed the work so I'll have to check the position of the spring clamps when I get the car home. Going to try the CLR radiator cleaner now that the heater hoses can be removed.

 

[Chris142]

I just spent $500 on a heater core flush which didn't work. The shop wants $4,500 to replace the heater core. I haven't picked up the car but I have my reservations that they actually performed the work so I'll have to check the position of the spring clamps when I get the car home. Going to try the CLR radiator cleaner now that the heater hoses can be removed.

That's about $3000 too high.

 

[BMWTurboDzl]

That's about $3000 too high.

Must be the BMW tax of $3,000. haha. My more important concern is having to explain this to my wife but it is what it is.

 

[slacktide_bitog]

UPDATE

so it seems like the heater core is fine, and that it's not leaking

It was just low on coolant. I topped it off, and I have driven it on some long drives a few times, and the coolant level remains full. In addition, it is not damp in the passenger footwell near the heater core.

 

[f355spider]

I just spent $500 on a heater core flush which didn't work. The shop wants $4,500 to replace the heater core. I haven't picked up the car but I have my reservations that they actually performed the work so I'll have to check the position of the spring clamps when I get the car home. Going to try the CLR radiator cleaner now that the heater hoses can be removed.

Ask them what their process is to flush the heater core. What products and tools did they use?
While chemicals can help, you need an air compressor and one of the flush tools posted above to get this cleaned properly and to last.
The tools are not expensive. Hopefully you already own an air compressor.

 

[BMWTurboDzl]

Ask them what their process is to flush the heater core. What products and tools did they use?
While chemicals can help, you need an air compressor and one of the flush tools posted above to get this cleaned properly and to last.
The tools are not expensive. Hopefully you already own an air compressor.

Ya the office guy said his tech was going to use a BMW tool. I'm thinking it was the Lisle tool which includes a connector It. I have the tool myself but without the air.