2000 ssei obd codes on my trip east

[bobsbonny]

on my way back from south dakota I encountered several obdII codes after
1.) a sudden drop in power during slight acceleration
2.) the tracking system de-activating in snowy conditions
3.) "service engine soon" indicator light displaying
The relevant codes I found were P0300,for (no.1 I presume)
and P0128 for no.3 (I believe...) the only way I was able to re-activate the tracking sys was to turn the ign. off for a few min. then restart...Any ideas ?????

[MKMike]

Actually, neither code has anything to do with the traction control.

P0128 is for the engine coolant temperature sensor
The code appears when the ECT sensor indicates that the coolant has not reached the proper temperature after a set amount of time.
It could be low coolant levels, a faulty ECT sensor or a bad thermostat.
If your engine has suddenly lost coolant, then you'll need to check for leaks.
Unfortunately, the leaks can be internal (intake manifold gaskets leaking), which must be addressed without delay to prevent engine damage.

P0300 is the code for random cylinder misfires
This link can help explain many of the possible causes http://troubleshootmyvehicle.com/gm/3.8 ... re-codes-1

It is possible that the temperature reading was off enough to tell the computer to lean out the fuel mixture too much---and cause the random misfires.


The traction control can be a connector that is no longer waterproof and is shorting out, makes poor contact due to corrosion or a wire to the wheel speed sensor has rubbed through or a failing sensor itself on the wheel bearing hub assembly.

If you haven't yet seen it, here's the common problems thread http://troubleshootmyvehicle.com/gm/3.8 ... re-codes-1

[michtom]

P0300 is the code you need to investigate. The pcm will tell the ebtcm to turn traction control off when it sets.P0300 can be caused by a multitude of problems. Start by checking for any spark or fuel problems.

[AJT2004]

I would start with some basic items first, especially if you are overdue for a tune-up;
plugs and wires
air filter
PCV valve
cracked vacuum lines
inspect engine wiring

As earlier suggested have you been losing coolant?

[bobsbonny]

I first want to thank everyone for their responses.to make a long story short,I just had a new block put in 2000+ miles ago and havent seen a drop of coolant leak.the top end has 115k original miles on it w/ new plugs and wires.all the work was done at a dealership so im preety sure all the work was done by a certified mech.im replacing the temp sensor and the thermostat.I'll be looking at the links in the responses,so hopefully I can track down the misfiring.thanks again for the help gentlemen,greatly appreciated.I'll follow up on the results .

[bobsbonny]

well, it wasn't coolant thermostat, or temp sensor....back to the drawing board

[MKMike]

well, it wasn't coolant thermostat, or temp sensor....back to the drawing board

Actually, it most likely was. Read on....

A very odd "feature" of these cars is that, after replacing the ECT, if you don't clear the codes, the cooling fans both come on as soon as the car is started---which causes delayed warm-up of the engine.
Delayed warm up sets the P0128 code, so it is self-perpetuating if the codes don't get cleared by you.

Use a scan tool and clear the codes.
My bet is that the P0128 will disappear and the car may run better, as well.

I should add that if the random misfire code returns, then I would follow the suggestions by
AJT2004 to replace the
air filter
PCV valve
look for cracked vacuum lines
spark plug wires

AND also replace the spark plugs and fuel filter.

This way, you will have eliminated the most common and cheap culprits.

[bobsbonny]

all of your suggestions have been applied and I'm still back to square one, along with a new code, P0341

[MKMike]

all of your suggestions have been applied and I'm still back to square one, along with a new code, P0341

The coolant temp sensor obviously was bad but wasn't the entire problem.
Hopefully, you cleared the P0128 code with a scan tool so the cooling fans no longer come on at startup.


P0341 is the code for the camshaft position sensor.

Troubleshooting steps and info here:http://troubleshootmyvehicle.com/gm/3.8 ... m-sensor-1

I will add that the service manual says to check ignition wires for arcing to a harness, carbon tracking or signs of damage, faulty coil or ICM.

[bobsbonny]

thanx Mike,I have new ign. wires w/ no signs of damage ect.,checked all the coils previously, cleared all the codes, and haven't had a recurrence of any SES light or codes but for how long remains to be seen. thanx again

[MKMike]

You're welcome.
Hopefully, you'll get no more codes.