CEL and Car Taking Forever to Heat up...

[JJPA4SE]

So... I noticed that the car was taking forever to heat up. Then I noticed that the cooling fans are kicking on when the car is cold. Then I got a CEL. FWIW the AC still works with no problems and the car does eventually heat up.

Here is the VAG scan (I cleared it the first time I got it and got the same thing the second time with this being the only code both times)..

1 Fault Found:

18613 - Performance Malfunction in Cooling System
P2181 - 008 - Implausible Signal - MIL ON

I searched on here and I found two possibilities with one being easier than the other, a coolant temp sensor replacement (easier) and a thermostat (harder). without posting this exact thread before I decided to give the coolant temp sensor (against the firewall) a shot using this writeup. It went well but after I did it the problem was not fixed (the CEL has not come back on yet but i think it will tomorrow).

So before I go doing the thermostat i'm seeking some advise either suggesting something else or confirming the need for a thermostat. I am also posting this so someone else that may stumble across this problem has a search result (as I really didnt have anything exact during my search).

So i'm left with the lower coolant sensor and/or the thermostat unless someone can provide another fix.

TIA for the help!

[cmlteg]

most of the time when u get that fault its your thermostat. Its sound like its getting stuck open

[eg3232]

he's right, probably a thermostat, I would go ahead and replace the ECT too
though.

[JJPA4SE]

he's right, probably a thermostat, I would go ahead and replace the ECT too
though.

Why replace/What is the ECT? I'm not being a smarty i'm just curious... Also.. i searched around for the thermostat online (PMS and ECS).. $100+ for that sound right??

Thanks for the help.

[absolutegtr]

SAME EXACT problem/scenario for me.

First your thermostat is bad. It is sticking open, that is why it is taking forever to heatup. Replace that (it is that $100 one you mentioned above)

And two you have to replace your ECT sensor as well (ECT=Engine Coolant Temperature). That is responsible for your fans kicking on when it is cold (further impedeing your car to warm up). It is about $25 and is located at the back of the head against the firewall.

[JJPA4SE]

^^ahh ECT=Engine Coolant Temperature, I shoulda caught that. I did the ECT at the firewall already (this afternoon). What about the one at the lower radiator hose, is that necessary? Is it ridiculous for the thermostat to go @ 56k?

[absolutegtr]

No, the one at the bottom should be fine.

My thermostat went out at 87K miles (when I bought) and it was a florida vehicle where it is always hot....so who knows when exactly it did go out....not a bad DIY at all....

[eg3232]

Just the one near the firewall will do. And no, its not ridiculous for it to go out at 56k, but 100$ sounds like way too much, check the dealer, I believe they are about 50.

[absolutegtr]

/\ nope....they are definetly around $100.....

It is NOT just the thermostat you are buying it is the WHOLE plastic housing as well.

[eg3232]

why?

[absolutegtr]

why?

Are you asking "why is it $100"?

[JJPA4SE]

thanks for the help everyone... thermostat on order and this will be my weekend project. FWIW this is the writeup i'm going to use, Click.

I hope this thread is useful to someone who runs into this problem in the future.

[TCHUN003]

yeah it takes my car forever to warm up too. I thought it was because of my testpipe or FMIC because it started to happen after I installed them.

[JJPA4SE]

Repair complete! Problem fixed.

I did learn that after draining the fluid from the lower ECT port there is still more fluid in the system. When I took the top hose off the thermostat coolant came pouring out and then when I got the thermostat off the block even more came out (both of which were unplanned spills). So, maybe the system needs to be pressurized to force the rest of the coolant out or maybe because of the way my thermostat broke it did not allow the coolant to leave the block.

Also, when putting the coolant back in the recovery tank filled up and after warming the car up for the first time it stayed steady. Then after running it down the street I popped the hood to find the recovery tank empty.. so make sure you check the fluid level after you drive it down the street and after a day or two of driving (I dont think I did anything wrong, its full now).

[JBM]

Thanks I might have to do this. My fan stays on constantly. It started after I did the coolant flange on the back of the block. I guess Ill flush and redo it again.
-Jared

[Maverick]

how many miles does your car have now? maybe time to do the timing belt job.

[Noodle]

I now have to do the same thing. I'm about to hit 66k (I think).

Blah, there goes my Penguins playoff tickets lol..

[Laconvail]

Repair complete! Problem fixed.

I did learn that after draining the fluid from the lower ECT port there is still more fluid in the system. When I took the top hose off the thermostat coolant came pouring out and then when I got the thermostat off the block even more came out (both of which were unplanned spills). So, maybe the system needs to be pressurized to force the rest of the coolant out or maybe because of the way my thermostat broke it did not allow the coolant to leave the block.

Also, when putting the coolant back in the recovery tank filled up and after warming the car up for the first time it stayed steady. Then after running it down the street I popped the hood to find the recovery tank empty.. so make sure you check the fluid level after you drive it down the street and after a day or two of driving (I dont think I did anything wrong, its full now).

You cant just dump coolant in the tank. A cooling system must be bled of air. Thats why the bottle was empty. Next time remove the bleeder screw from the upper coolant pipe and add coolant til it comes out of the bleeder screw opening.

[JBM]

how many miles does your car have now? maybe time to do the timing belt job.

directed towards me? I did it at 80K and I am at 88K

[JJPA4SE]

how many miles does your car have now? maybe time to do the timing belt job.

Directed at me? I'll be at 60K in three weeks... guess i'll start thinking about it this summer... i did notice that that my belt tensioner is shaking like crazy at idle (different belt but it still worries me). service manual says 75K, not sure how i feel about that.. (conversation for another thread)

You cant just dump coolant in the tank. A cooling system must be bled of air. Thats why the bottle was empty. Next time remove the bleeder screw from the upper coolant pipe and add coolant til it comes out of the bleeder screw opening.

thanks, learn something new every day... i don't remember seeing that in the writeup or in bentley.