Heat only works with "Recycle Cab Air" on

[Severian]

Hey everyone, my wife and I bought our 318ti over the weekend. What a car! I'm really happy that I found a place on the net where enthusiasts gathered to discuss them...perhaps you can help us? The heat doesn't work in the car.

But now that I've said that, I have to amend it by saying that we stumbled on some heat in the car last night by accidentally having the "Recycle Air" button depressed. If that button is not depressed we get an ever-so-slight amount of heat from the vents, but it doesn't warm the cabin up very much. The engine temps seem normal (half way between hot and cold most of the time).

Any ideas why we get some heat sometimes and not others?

Thanks so much in advance

[cali-ti]

when you say "halfway between hot and cold MOST of the time," what do you mean? it should come up to operating temp (needle basically straight up, halfway between hot and cold) and stay there. if it drops when you get up to highway speed or anything like that, you most likely have a bad thermostat (pretty cheap, ~$20 from pelicanparts.com or other sources, good time to drain/refill the cooling system since you'll be having to open the system up anyway). thermostat is a fairly common problem. otherwise, my guess would be the heater control valve.

[Severian]

Thanks for the prompt and helpful reply, cali-ti. It looks like the temp needle is almost always pointing straight up, although sometimes it tends very slightly to the cold end. But for the most part it's acting fine (right?).

So the heater control value could be the reason the heat won't function normally? Do you think this something that we could change on our own? (well, my step son anyway...I'm a total noob with cars)

EDIT

http://www.carpartsteam.com/BM_318ti_Climate+Control_A~C+Expansion+Valve_019.html
I used CarPartsTeam and found this Expansion Valve (related to Climate Control). Is this the heater control valve that you're speaking of? There are other parts related to Climate Control and other 318ti systems on that site, too.

[cali-ti]

i believe it's #5 in the diagram here:

http://www.realoem.com/bmw/showparts.do?model=CG73&mospid=47506&btnr=64_0202&hg=64&fg=18

btw, you'll most likely want to link to www.realoem.com/bmw (and memorize the last 7 digits of your VIN) as this site is very handy for looking things up.

i would also suggest doing a search on "heater control valve" or "heater bypass valve," as that netted me some other threads on this same subject.

[Severian]

Odly the last 7 digits of our VIN generate an errror. The last 7 digits for our VIN are 2 letters followed by 5 numbers (like this, XX00000). I was able to find the diagrams associated with the MONTH/YEAR of our model as specified on the car's sticker, but I wonder why the VIN didn't work.

BTW, kick ass site!! My wife works for a contracting company that makes parts manuals like this for heavy lifting equipment (Komatsu, Cummins). I bet she'll get a kick out of this site.

The missing link is buying an equivalent non-OEM part, right? Because you can't buy through that site yet. What process do you use to go from finding the OEM part number to having the real part mailed to you?

Thanks for all your help, cali-ti, it's cool of you.

[cali-ti]

hmmm ... i think they're all 2 letters + 5 digits. very odd that it gen'd an error. where did you source your vin #? there are multiple locations on the car where it's listed, maybe they don't all match? keep in mind, that's the month and year of manufacture not sale so it may differ. eg: bought mine in oct 1996, but it was man'd in 05/1996. the big differences were during the switch from OBDI (1995) to OBDII (1996+) so unless you're in that region, you most likely will be ok (at least for this part).

i usually take the bmw part # and then go to a dealer to get bmw original parts. where are you located? i dislike the dealer in my area, so i usually use www.crevierbmw.com even though it's nowhere near me (i'm in WI, they're in CA). others like pacific bmw ... bimmerparts.com is usually good (if they have the part) ... pelicanparts.com can be good (although i'm not sure they use original bmw parts). crevier gives bmwcca discount for all internet customers. if you're a bmwcca member, you usually can get 15-20% off parts from the dealer, easily worth joining if you're going to be servicing your car yourself. i LOVE the realoem site ... although it's been dangerous to my pocketbook, lol.

the site is all about helping each other out. the only reason i know anything is because of this site :)

[Severian]

hmmm ... i think they're all 2 letters + 5 digits. very odd that it gen'd an error. where did you source your vin #? there are multiple locations on the car where it's listed, maybe they don't all match? keep in mind, that's the month and year of manufacture not sale so it may differ. eg: bought mine in oct 1996, but it was man'd in 05/1996.
I made sure the VINs on windshield, driver door, and rear tag matched when I bought the car. The full VIN is WBACG7323WKC30112...it works on carfax but not on this site. Wonder why? I found the production month & year on the sticker itself, so even though it's a 98 the production date was 11/97.

This is the first car we've ever owned that I've fallen for...most cars I abuse, I admit it! Main reason I was looking to establish a 3rd party vendor for these parts was to save som $$ when we take the car in for service, but I'm going to attempt simple maintenance myself (oil changes, coolant flushes, etc). OEM parts are more expensive than 3rd party parts, right?

I'm a computer guy. Cars are so similar in mentality, yet so different in practice! For example the spark plugs in our M44s are buried, my step-son's dodge Neon's plugs are out for the world to see. Since I build computers from OEM parts I never deal with proprietary construction quirks like this.

[cali-ti]

plugs are pretty easy to get to though. bmw actually designs stuff quite well for serviceability (unlike many others) ... you do certainly have that occassional pain in the a$$ part to get to/remove/replace though.

non-oem may certainly be cheaper and it really depends on what it is as to whether or not i'd use non-oem. check the difference in price (if you can find non-oem) and then ask yourself if it's worth not using the bmw part.

a couple of months ago, i'd never done anything more than oil changes, brake pads/rotors and the like. due to the info provided on this site, i'm getting into a lot more, perhaps you will too. if nothing else, you'll end up with a lot more tools if you start wrenching yourself. can't believe how many i've gained, lol. can't wait to get a hydraulic lift like they have at car shops, that'll be sweet ;)

[Severian]

Well, this is off topic but I have to ask...how the hell do you get to the plugs?? This is a shot of the M44 (not my car exactly but it illustrates it)...I see where the plugs are located, under the intake system is it? How do you get down there to each plug? Does the intake system detach easily?

http://users.belgacom.net/ddddv/engines/1900_gr.jpg

I have a feeling that cars could be a fun new thing to learn. But right now I'm a total newb.

[cali-ti]

that black plastic piece that says BMW in white comes right off (two little plastic screw caps - just turn like 1/4 turn) and they reside right under there. even a tool to pull the plug wires from the plugs included under there :) need an extension to get down to the plugs, but i'm guessing most people have those in their kit. i think a plug removal tool might be included in the tool kit that came in the trunk too, i forget. you're thinking it's way harder than it is :)

[Severian]

Bingo, thanks dude. And yes, I was definitely thinking it was much harder!