skye2388

Hello guys,

I got my catalytic converter replaced in August and the P0420 code that I was getting has gone away.

Now more codes are popping up:

P1705 revolution sensor circuit malfunction

P0120 throttle/pedal position sensor A circuit

P0130 O2 circuit (Bank 1, sensor 1)

P0133 O2 circuit slow response (bank 1, sensor 1)

P0135 O2 heater circuit (bank 1, sensor 1)

P0125 insufficient coolant temp for closed loop fuel control

When I reset the codes, P1705 and P0125 come up almost immediately (within 10 miles of driving). A few weeks ago, I noticed my coolant overflow reservoir was completely empty so I added coolant to it but I realized shortly thereafter that I did it incorrectly so today I went and got my coolant drained and refilled (from radiator and reservoir). All above codes reappeared.

I think these are all minor issues but I did some research and this is what I THINK I should be doing.

First thing I want to focus on is the P0125, P0130, P0133, and P0135 codes since I THINK they are all related. The guy who drained and refilled my coolant knew about the P0125 code but not the other ones and he thought a stuck open thermostat was the cause and wanted to replace the thermostat and gasket for $150. I held off and did some research and found that the ECT should go above 160-170 degrees F within 15 minutes (source: http://repairpal.com/OBD-II-Code-P0125).

Freeze Frame data:
P0125
ECT (deg F) 194.0
IAT (deg F) 122.0

My gut feeling is telling me faulty Oxygen sensor (bank 1, sensor 1) might be causing all this trouble after reading this: http://www.justanswer.com/toyota/16k...ode-p0125.html
but then again I'm not an expert. Any advice on this particular case of P0125?

Also, research has told me that P1705 is just a simple sensor replacement located on the exterior of transmission (on top of transmission?). Could anyone confirm that I'm correct??

Experts - your advice would be greatly appreciated. Thanks in advance.

moonphase

The first thing I would address is; Where is the coolant going that you are needing to replace. If for instance you have a blown head gasket, repairing the other issues becomes mute. If coolant is being burned via a blown head gasket, the coolant will kill both the oxygen sensors, and catalytic converter in a very short time. When the converter was changed, the mechanic should have addressed the cause of the converter going bad. ie running too rich, coolant in the exhaust, etc. Your ect temp sounds right as the thermostat starts to open at 180 deg, and is fully open around 200 deg. You might want to let a qualified mechanic solve this one as it will likely save you money in the long run. Good Luck

skye2388

I honestly just thought the coolant dried up or vaporized. Is that possible?

I understand the coolant circulates in the engine through the radiator or something along those lines. Where is the coolant supposed to go?

Anyways, when I got it drained and refilled I asked the mechanic if he noticed any leaks or anything, he said no. Also, I DO indeed notice a foul smell coming from my exhaust and a lot of white smoke coming from the exhaust and continuing while I'm driving but I thought that was because the new catalytic convertor I replaced had already gone bad (i heard some aftermarket Cats were risky since they could go bad almost immediately). Could this mean the coolant is leaking into my exhaust system via the blown head gasket? Any advice?

PuReChaos

smell your exhaust briefly, if its sweet smelling most likely leaking coolant from a blown head gasket.

skye2388

It actually doesn't smell sweet (but all the other symptoms I noticed were there ie: white smoke, oxygen sensor codes, abnormal coolant loss) so that debunks my theory. I brought it to a mechanic and he tested it - he doesn't think it's a head gasket. PHEW! saves me 1-2k.

He thinks the coolant might be leaking from somewhere near the rear of the engine thus causing the coolant to evaporate from hot engine temperatures leaving no signs of a leak underneath the car.

He also recommend I replace my valve cover gasket since it's leaking oil a bit and he has to open that up to take a closer look anyways.

Thoughts?

PS - Is it possible the coolant just dries up or evaporates rapidly due to being an old car? I drive on a highway pretty much everyday - 20 to 30 minute commute to work and 40-45 minute commute into NYC...I also drive it upstate about once a month which is a 2.5 hour drive.

moonphase

Check the coolant level, and fill to appropriate line. drive the car for 1/2 hour to ensure proper operating temp. Park the car over a large sheet of plastic overnight and in the morning go looking for coolant drips on the plastic. If you find drips, investigate the engine above the drips to find the leak. If you do not find drips, you likely have an internal leak if the coolant level is lower in the reservoir.

skye2388

So on Thursday the mechanic tested the coolant to see if the head gasket needed replacement. He did so by opening the cap on the radiator putting in a funnel and filling the funnel with coolant and turning the engine on. Bubbles were supposed to indicate a leaky head gasket. There were no bubbles thats why he doesnt think it's the head gasket.

Then the following day (Friday 12/6/13), the coolant overflow tank was empty and my car wouldnt start. No clicking no nothing - I had a gut feeling it was the battery but couldn't get it to start regardless so had it towed to my mechanic and replaced the battery terminals and the car started just fine. I have no idea where the coolant is going... I will give the plastic sheet a try... although im pretty sure I have a internal leak...

My father also told me that it could be that the coolant tank (not the overflow tank) is not full...thoughts?