LOW running temp and running quite rich

[clutterbucker]

Alright, I realize there may be a correlation between the two. Motors that run rich run cool, correct? I had the problem narrowed down to the cold start valve, until someone pointed out to me that the m20b25ers don't have cold start valves?!? wtf?

What the hell is wrong with my car that the exhaust REEKS of gasoline and it never gets above 1/4 on the temp gauge even on hot days (unless I let it idle for a loooooooong time). I'm getting truly sick of this, and I can't imagine that its good for my motor or gas mileage to run so cold all the time.

PLEASE HELP.

p.s. I already tried putting in a K&N cone with heat shield to get more oxygen to the motor. It helped with power and sound a bit but definately not with the gassy smell of my exhaust.

[Axxe]

Oxygen sensor is a good place to start. It sends info to the ECU about how rich/lean the car is running and the ECU corrects. I had this problem aswell and a quick sensor change made everything smell like roses.

[Spaz]

Re: LOW running temp and running quite rich

Alright, I realize there may be a correlation between the two. Motors that run rich run cool, correct? I had the problem narrowed down to the cold start valve, until someone pointed out to me that the m20b25ers don't have cold start valves?!? wtf?

What the hell is wrong with my car that the exhaust REEKS of gasoline and it never gets above 1/4 on the temp gauge even on hot days (unless I let it idle for a loooooooong time). I'm getting truly sick of this, and I can't imagine that its good for my motor or gas mileage to run so cold all the time.

PLEASE HELP.

p.s. I already tried putting in a K&N cone with heat shield to get more oxygen to the motor. It helped with power and sound a bit but definately not with the gassy smell of my exhaust.

check your thermostat, replace it, and go from there, cars will run rich when cold to help warm them up quicker. figure out the cold running first then, see if you have a rich problem.

[clutterbucker]

I simply put the two together as one problem. I figured it was running so cool because it was running so rich. I coul dbe wrong, however. I'll replace the oxygen sensor a.s.a.p. If the O2 sensor is the problem, do you think it couild possibly make both my A/F ratio even and the car actually warm up once in a while?

[EverWiser]

It could also be a temp. time switch problem...If it goes bad and/or gets disconnected the ECM will not know that the car has warmed up. It's not the same as the temp. sender...1/4 on the temp gauge sounds OK to me. Both of these are mounted on the thermostat housing. I'd check all your connections in this area first.

[hotghias]

Re: LOW running temp and running quite rich

[quote="Spaz"]

Alright, I realize there may be a correlation between the two. Motors that run rich run cool, correct? I had the problem narrowed down to the cold start valve, until someone pointed out to me that the m20b25ers don't have cold start valves?!? wtf?

check your thermostat, replace it, and go from there, cars will run rich when cold to help warm them up quicker. figure out the cold running first then, see if you have a rich problem.

bingo. your ecu thinks the car is warming up and compensates by running a richer mixture... all the time. replace your thermostat FIRST, or at least take it out and check it. it's a hell of a lot cheaper than an O2 sensor, right?

[Axxe]

I'm sorry, didn't think of the thermostat. Go with that first, it's a lot cheaper.

[clutterbucker]

so it could have nothing to do with my O2 sensor?? wierd.

Let me get this straight. The car thinks its always warming up so it runs a richer mixture of fuel and air. That's because it is always warming up, so it would make sense, wouldnt it? Will throwing in a new thermostat make my car heat up quicker?

Today, I unplugged the O2 sensor and drove around and it made no difference. This made me think that the O2 sensor just might be the culprit. Here's hoping.

If the O2 sensor doesnt do it, I'll try for the thermostat. I don't see how it could be the thermostat still, unless its just stuck open and contantly running coolant through, even when the car doesnt need it. I've never heard of that happening though.

I'm so fu*king confused. Tomorrow hopefully my mechanic/godfather will have the O2 sensor and this will all be resolved. I'll update.

[FergU]

When the O2 sensor is unplugged, the ECU returns to default codes. So, if you unplugged it and nothing changed, the O2 sensor is good.

[hotghias]

so it could have nothing to do with my O2 sensor?? wierd.

Let me get this straight. The car thinks its always warming up so it runs a richer mixture of fuel and air. That's because it is always warming up, so it would make sense, wouldnt it? Will throwing in a new thermostat make my car heat up quicker?

Today, I unplugged the O2 sensor and drove around and it made no difference. This made me think that the O2 sensor just might be the culprit. Here's hoping.

If the O2 sensor doesnt do it, I'll try for the thermostat. I don't see how it could be the thermostat still, unless its just stuck open and contantly running coolant through, even when the car doesnt need it. I've never heard of that happening though.

I'm so fu*king confused. Tomorrow hopefully my mechanic/godfather will have the O2 sensor and this will all be resolved. I'll update.

WHEN A THERMOSTAT FAILS, IT NORMALLY STICKS OPEN ALL THE WAY, LETTING COOLANT THROUGH ALL THE WAY, ALL THE TIME. SO YOU NEVER FULLY WARM UP. THIS IS COMMON. sorry. had to get my point across. on my car, the thermsotat failed and stuck open (underheated). then the german replacement thermsotat failed 2 years later and stuck closed (overheated). a thermostat is well under 20 bucks and easy as hell to do. i got my latest chinese thermostat at autozone.

[clutterbucker]

you know, that makes a hell of a lot of sense. Thanks, I'll spare myself the hassle of spending 91 bucks on an oxygen sensor and go with the thermostat idea. I'll check it tomorrow when I take it in to the shop to tell them I don't need the O2 sensor. How the hell do you guys know so much more abou my car than the local import shop. these guys work on ONLY imports......old german ones.

Anyway, thanks.

[ColdAccord]

let me know if you need a hand changing the tstat. takes about 1 minute

[38927]

my car is running a tad over half, why might this be?

[clutterbucker]

tad over half?

is this mostly only when you're under 10 mph of when moving quickly?
if only when moving slowly or stopped, it could be your fan/fan clutch. If it happens when you're moving quickly, maybe your Tstat is older than it should be....and doing the opposite dance that mine's doing.



b.t.w. Thanks andre , but my godfather works at a mechanic shop and he's going to throw it in for me.

you guys were helpful.....I appreciate it

[clutterbucker]

ok...so my godfather is NOT going to install the Tstat for me. Anyone know if all I have to do is open up the housing and throw it in? or are there some other steps I have to take. ie.: should I run out and buy some coolant.....


EDIT: I just replaced the damn thing. It was ripped to shreds
Thanks for helping me to not waste time and money on an oxygen sensor.