530 thermostat

[freaker]

Is it seriously possible that a thermostat from oriellys is bad after a month?! Girlfriends car only gets quarter of the way up on temp gauge. Was in the middle where it should be up til a week ago.

[shortedaman]

Did you bleed it correctly?

[freaker]

Well i believe i have. I dont have any air coming out of the bleeder screws. Its not throwing an engine code like it did last time when it did need a thermostat. It was fine for a while. Now i dont know wat the hell is going on. I get a low coolant ding on the dash info too. but it doesnt take any.

[tmvE39E53Z32TT]

May just be the coolant temp sensor and coolant level sensor. At least clean the contacts on those and see if it improves.

[rdl]

I can't think of a reason other than a defective thermostat for the engine not reaching normal temperature. You might count your blessings that it didn't fail closed and cause an overheat. If it had to fail, better open than closed.

As mentioned above, it's possible that the temperature sensor or the gauge has gone defective. You can check a couple of ways to determine if likely.
1) "unlock" the instrument cluster and bring up test 7.1 which displays the sensor reading. The sensor in the cylinder head has 2 thermistors: one for the gauge & one for the DME. While the engine is running one of the thermistors is displayed by test 7.1. When the engine is turned off by turning the ignition key to position 1 (accessory, not position 0 at which one can remove the key) the other themistor is displayed by 7.1. The 2 readings should agree within a degree or so; it's unlikely both would fail the same way at the same time. If not, replace the sensor.

EDIT: oops - test 7.0 is coolant temp, not 7.1 as I described above. I hope this correction is soon enough to avoid a wasted purchase &/or replacement.

2) use an IR thermometer to read the temperature of the upper rad hose as close to the thermostat housing as possible.

FYI the gauge should read as follows
top of blue segment: 50C
1/4 tick mark: 60C
vertical: 75 to 113C
past vertical: over 113C

Regards
RDL

[freaker]

I will have to try that out. It doesnt have good heat like it did before. Obviously with low temp on engine.

[rdl]

I will have to try that out. It doesnt have good heat like it did before. Obviously with low temp on engine.

Reduced cabin heat suggests that engine temperature is in fact below normal. In other words, a faulty thermostat is more likely than a sensor or gauge error.

Regards
RDL

[tmvE39E53Z32TT]

I will have to try that out. It doesnt have good heat like it did before. Obviously with low temp on engine.

Agree on rdl's comment. The T-stat stucks open. Hope you get quality one this time.

[freaker]

Agree on rdl's comment. The T-stat stucks open. Hope you get quality one this time.

I knew that was coming lol. You are right tho. Thanks guys.

[rf900rkw]

Also keep in mind that if the engine is overheated badly, the thermostat can deform and start opening earlier.

[EricP]

Also keep in mind that if the engine is overheated badly, the thermostat can deform and start opening earlier.

That is exactly what my old thermostat did.. took it off a crap motor and onto the new one and it was opening too soon.

[cbell2112]

I recently had my thermostat and housing replaced by an indie. The old thermostat was stuck open as the gauge was reading just below 12 noon and I saw a decrease in fuel economy of about 2 mpg plus it was throwing a code indicating faulty thermostat. After replacement, the fuel economy is back to normal but the gauge still shows just below 12 noon. The part number listed on the invoice suggests that it is not the thermostat which runs a bit cooler. I am questioning whether they actually changed the part. What do you all think, just a coincidence?

I just busted them today for not changing another part(power steering hoses) that was supposedly replaced 2 years ago.

[Aryana]

I would be quite suspicious of all their previous work after catching them red handed.

[cbell2112]

I am suspicious but the fact that it hasn't thrown a code and the mpg have improved makes it difficult to come to a conclusion. Anyone change a thermostat and NOT have the gauge return to dead center?

[Gumbi4u]

Most of the time, a proper bleed takes care of these issues.

[AnotherGeezer]

Most of the time, a proper bleed takes care of these issues.

I recommend leeches.