2000 S70 Ecu Problems/cel

[767driver]

This was my last post on this issue:

OK, here's the latest. Installed the new cloned ECU in the car, started up just fine. Drove it for about ten minutes, and sure enough, check engine light comes back on. Had the codes read out and they are all the same codes I had before swapping the ECU, so it seems to me that maybe my ECU wasn't bad after all. I won't know for sure until I can get these codes permanently cleared and then try to reinstall the old ECU and see if it works.

Here are the codes I've got:

P0031 Front heated O2 sensor preheating, permanent fault

P0037 Heated O2 sensor bank, signal too low 1, preheating

P0136 Rear heated O2 Sensor, signal missing, permanent fault

P0245 Turo control valve signal too low, permanent fault

P0445 EVAP emission sys valve, signal too low, permanent fault

P0448 leak diagnostic unit, valve, signal too low

P1655 TCM/PCM communication line malfunction

P1332 CVVT solenoid

So, I guess I will try to replace the front O2 sensor, check the connections for the rear O2 sensor (I replaced it about a year ago), replace the TCV (just got the new HD one from IPD). As far as the CVVT solenoid, I replaced that about a year ago, but I used the connector provided, rather than soldering the wires directly to the unit as had been suggested on other forums. I'll give that a try...

Does anyone have any suggestions for the EVAP system and the rest of the codes 445, 448, and 1655?

Thanks.

So, I replaced the front O2 sensor, as well as installed a new TCV from IPD, and adjusted the turbo waste gate to the proper setting. Still had 4 codes remaining, 445,448,245,1655. Did some searching on MVS, and found someone with the same issues. They found a 20amp fuse in the main fuse box blown, a fuse that controlled some of the environmental control systems (5th fuse, counting left to right). So, I checked my fuse box, and sure enough, this fuse was blown. I replaced it, reset the CEL and sure enough, NO MORE CEL!

I've been fighting this ever since my ABS module went bad. After I replaced my ABS module I still had all these codes that wouldn't go away. Lots of frustration and needless expense, and no help at all from the dealer, who sent me down the path of replacing the ECU, which was not necessary at all. So, thanks for the input from the forum, and I hope my experience can save someone else from repeating my mistakes.

[Ghost Shadow]

did you seat the ecu properly?

[Matty Moo]

Have you tried scanning using a different scanner? Such as one that will get deeper than just the generic OBD codes? I don't know which one you're using, but not all of them will give manufacturer specific codes. for the most part, don't trust the provided definitions with most of the basic OBD scanners.

p1655 is related to the CVVT, as an example. Not a comm problem.

Also, who did the timing belt last? It's easy to throw off the timing on the CVVT side and throw some CVVT codes. Even locking the cams you still need to go forward and then come back 1/4 turn . The last one I did I just locked the cams and had instant codes. I ended up being one tooth off on the exhaust side and ended up having to go forward then back 1/4 turn, loosen the tensioner and go from there. Problem solved.

When you did the rear 02 sensor, did you use an original OEM part, or splice/solder a new one in? That goofy connector is pain in the ass to get to seat correctly also.

This is what I would do.

First check all of you electrical connections. Battery, B+ cables and grounds.

Your EVAP and TCV codes point toward a vacuum leak, rather than electrical. Me, I'd replace all of my lines if they were original. If they are original, just replace them or have it smoked to see where it's leaking.

check the 02 sensors. I personally would read into what the live data says about them.