2000 v70xc se with 125k

so i had the following list,

P0445
P0448
P0245
P0037
P0031
P1332
P0136
P1655

another symptom was anemic acceleration.

i replaced both o2 sensors and the maf sensor. the acceleration seems to be back to normal an P0136 and P1332 are gone. however the balance of the codes remain.

i am thinking it may be an electrical short to ground somewhere as all faults indicate low signals. i know what fault each code represents. i am thinking that they may all be related. is there are common wiring harness where i can begin probing for a short?

once the codes are cleared, the cel will come back on immediately. this also makes me think there is a short to ground.

any insight is appreciated.

 

I would start with the 0037 and 0245 turbo control valve that might be bad.

The o2 codes might just be the computer has been to slow to catch up with the new parts.

But the 0445 and 0448 are the evap system codes and can also set the o2 codes as it is a vacuum leak.

 

thanks tech.

i am having trouble locating the turbo control valve. there is a vacuum operated diaphragm valve which controls the waste gate on the turbo, but there appears to be no electrical connections.

can you point me in the right direction?

 

It is usually mounted right on the side of the air box.

 

thanks again.

now that i think about it, does the solenoid control the diaphragm valve? if so, then i should be able to follow the vacuum line.

 

Yes it does. Yes you can follow the hose.

 

thanks tech. i found the valve, right under my nose. i did find a hole in one of the lines. i have patched that and cleared 2 codes, i am left with the following,

P0445
P0448
P0245
P1655

i have tested the valve just be applying 12 volts, the valve works. i check the connector with the key in the "on" position and the engine running and only have 3.5 volts, when does this valve get energized?

also, i have checked the evap valve which is next to the radiator and opens the canister to the intake. this valve works but the connector has only 3.5 volts with the key in the "on" position and engine running. when should this valve be energized?

 

i don't know if this is problem, but between the ground leg on each connector and the negative terminal of the battery, i am measuring 8 ohms. i would think this should be a dead short. could the ground be floating and causing weak signals?

 

recap:

had/have the following codes,

P0445
P0448
P0245
P0037
P0031
P1332
P0136
P1655

and acceleration was anemic.

actions: replaced both o2 sensors and the maf sensor

result: acceleration back to normal but all codes remain

found a vacuum leak at the turbo control solenoid, fixed, codes remain. valve appears to be functioning properly.

found the ground wire to the camshaft sensor pinched between head and plastic cover, fixed, codes remain (since ground wire figured this would not resolve codes)

cannot find anymore vacuum leaks in engine compartment. visually inspected and also sprayed intake cleaner to see if idle stumbled

there does not appear to be a leak in the j hose. there are 2 hoses, smaller to the intake and larger, i am assuming from the fuel tank. i removed the smaller at the canister at rear and blew into it. with engine off, i could not blow through it. the valve on the radiator shroud is functioning properly.

once i clear the codes, they come back immediately upon engine start. there does not appear to be any shorts to ground in signal lines from sensors.

the engine seems to idle and drive fine. any thoughts?

 

Now I wonder if your scanner is not clearing them all the way.

If you have clearly found and repaired faults the codes should be gone.

 

my scanner is a cheapy.

however, i am not sure i have found the actual faults. what are your thoughts on the voltages i mentioned in a previous post? also, when i probe between the ground lead on connectors and a grounding strap, i have about 8 ohms. i would think this should be much closer to a dead short. what are your thoughts?

thanks.

 

On the valves they are not activated with just the key on.
The evap valve is not activated till after the car has been running so long. Then with it running you should hear it cycle on and off to perform the tank test. When you clear that code it should not return right away. It usually takes about a day for the car to perform the test and throw the code.

The turbo control valve I believe doesn't get 12V till you hit full boost and the valve activates to drop the boost level down.

Not sure about the ground strap issue. If you want try running a temp ground and see if that makes a difference.

 

so, i am still battling these codes. i have checked everything, so i think with no luck.

the codes appear immediately upon the first start of the engine after clearing. could it be shorted pins on the ecm? has anybody experienced this issue?

 

Possible but not common.

 

Is there a list of fault codes for my V70 2005 ?