bizzy928

Hi All,

1992 SC400, 260000km, the check engine light is on and it is throwing out misfire codes. My fuel filter was leaking last week, so my mechanic cut it out and replaced the filter and part of the line. He thought the CEL was a result of the fuel leak so he just reset the code. Later that day the code came up again.

I don't know if this is related, but in the winter my engine temperature does not get any warmer that 1/4. I changed out my coolant about 2-weeks ago and there is no change. It doesn't matter if it is -20 or -1 outside, it never gets above 1/4 warm.

Do you think the cooling problem is related to the CEL/misfire codes?

Thanks in advance!

lilSCsteve

iTrader: (71)

I think the CEL is possibly this: Check your O2 sensors...might be the problem? As far as your cooling issue, have your mechanic check your thermostat...either way Let us know what's the culprit once you find out.

LEX_MAN

iTrader: (2)

Read the cell code and se what it is.Its very easy to do man.If you need help ask,and i'l tell you how to read codes.

The coolant problem is most likely your thermostat.You can actualy do it your selfits easy too.

stevechumo

iTrader: (5)

Your mechanic should have known that he should check the CEL code, and not by guessing it. You don't want to go back to that mechanic. He only knew how to turn the screws but got no idea what he's doing it for. That type of mechanic will waste your money and might give you troubles.

bizzy928

Thanks for the quick responses. Let me clarify that my mechanic did pull the codes after he fixed the fuel line and replaced the fuel filter. He related the misfire to the leaky fuel line and reset the code. I'll drive the car around for another month of so and see if the light goes off.

If it was the O2 Sensor, would the code specifically say "O2 Sensor"?

To replace the thermostat, do I need to replace the coolant AGAIN?

I'll keep you updated!

1985zcar

iTrader: (1)

I would recommend you find a new mechanic. A fuel leak from the fuel filter wouldn't cause a CEL to come on, lol...

Typically if an 02S is failed, then yeah you'll have a fault that'll say something like 02S No voltage sweep or something.

If you just replaced your coolant, then you can catch it in a clean containter and re-use it after installing the new t-stat. I did that when I replaced my water pump.

SHOLEXMAN

Sounds like your thermostat is stuck open and will not close. Cooling down the whole time and not wanting to gain heat. If your heater isn't working correctly either that should be the cause right there. With the misfire making sure that your plugs and wires have been changed and your caps and rotors are in good condition with no carbon trailing. If the o2 sensor is bad it would flash not throw the code lol sensor 1 bank 2 low voltage for example. Your mechanic sucks BTW fuel filters would NOT cause a code to happen utter BS!

bizzy928

Thanks all, I'll definitely have my thermostat replaced.

As for my CEL light. I did some searching it found that it also MAY be related to bad gas. My car has been in storage for 6 months (with fuel stabilizer), so it may be the tank is bad. I just burned through it and filled up. If it was the gas, would the light go off by itself? Or does the CEL always have to be "reset" to turn it off?

How would I reset my CEL? Can I pull a specific fuse?

SHOLEXMAN

Pull of the battery positive cable for 30 minutes or so at the most. That is with pre 96 models cause the ones 96 and after keep the codes in memory ,but don't show the light. There are jumper terminals on the top of engine jumper those and it should clear it along with a plug under the drivers side near the steering wheel. Do a search for it like ECU reset or code reset its cake man better then waiting for a answer on this thread.

stevechumo

iTrader: (5)

Why keep guessing? It's just like when you're itchy, you gotta scratch right on that. No guesstimate..LOL. You'll need to know what code the CEL means. It's very easy to do. If you need an instruction to do it, let me know & I can help you.

bizzy928

Hi All,

I just wanted to give an update regarding my cooling issue as mentioned above.

Parts Purchased
16325-62010 Gasket (22.30 CDN)
90916-03129 Thermostat (8.20 CDN)

Turns out that it was the thermostat that was not letting my engine temp get up the the "middle." My mech replaced the thermostat, and the car runs warm, and blows HOT heat again. Sure helps on the -19 degrees celcius days!

Thanks all.

The next issue to solve is the CEL: Code 25...