Need advice

[Bimmer360]

Originally Posted by 740iS

Much much worse. Doing the Tracy to Fremont commute now and since I leave in the mornings around 0330, traffic isn't too bad. But commute home from 1400 on and its stop and go on 680 from Mission Bl. (South end), over the Sunol grade and all the way to 84 to head to Livermore.

I stay on the freeway and then across on 580 which gets worse over the Altamont too.

Moved from the tri-valley to the Central Valley to get more house for the money, but the commute changes over the last couple of years is ruining that!

Can only hope that this was the fix, but if not I think the next step would be the throttle body and/or the accelerator pedal. Hate just throwing parts, but no diagnostic is proving one over the other either.

I bought my house in Lathrop in 2009 when everything was down and have been doing that commute and I used to leave home around 4ish and get off work at 3:30. Yeah Fremont man around the Frys electronics area and before 84 was a nightmare most of the time. Then yeah there is the Altamont Pass. Put 150K miles/year on my daily driver before and I was burned out. Took equity and decided to just take it and moved here in Denver. I work from home now.

[740iS]

Just a quick update, since this one isn't my daily driver, haven't been able to fully verify if this repair was the solution. But drove it to/from work yesterday and the 15 or so miles of stop and go traffic on my way home would cause the fault to return. Happy to say ran perfectly, no errors and even stopped to get the smog check done after returning to town and passed without issue.

Will drive it a few more times next week and if yesterday is any example, then I'd say this repair is a success.

[heatmizr]

Nice to hear 740is!

[740iS]

Well, damn! Since my '13 3.5i decided to spring a leak from what appears to be the expansion tank, I decided to drive the '08 over the last couple of weeks as a daily driver. Wife and I decided to keep it as our dog transport vehicle.

But on the way home yesterday, no messages on the OBC, but felt like I was losing power, so pulled over and decided to scan. Got the following:

002B70 DME: Variable intake system activation
0055D0 Message (steering wheel angle, 0xC4) error, receiver VTG, transmitter DSC
00604E RDC: RDC system
006057 RDC: Wheel electronics, rear right
006140 AL: Redundancy comparison, driver's steering angle
006EC4 DSC: steering-angle sensor, adjustment
00A6CF JBE: AUC sensor
00A6F3 CCC-A: Coding data error
00E723 No message (condensation sensor, 0x2D1), receiver integrated automatic heating
00E729 No message (automatic air recirculation control sensor, 0x2D0), receiver integrated

So another litany of errors and on the ISTA/D all show "No" under the Existent column with the exception of the two regarding the RDC. Anyone think that those errors are my actual issue causing yesterday's loss of power? After scanning and clearing (since I couldn't "fix" anything on the side of the road) it drove just fine the rest of the way home and back to work again this morning.

Any help is appreciated!

[740iS]

As an update: on the way home yesterday, got the limp home mode enacted again. This time there were some different codes as well as a couple repeats:

0055C3 VTG: AWD limp-home control activates. No DSC specified nominal torque
005F77 DSC: Engine management: interface
00604E RDC: RDC system
006057 RDC: Wheel electronics, rear right
00A6F3 CCC-A: Coding data error
00E723 No message (condensation sensor, 0x2D1), receiver integrated automatic heating.

As you can see, the RDC errors are becoming consistent and when I got home decided to scan again and only code that reappeared in the 20 miles home was again the RDC error. Starting to think this may be a bad right rear ABS wheel speed sensor. Any additional thoughts?

[Black-Forest]

You maybe onto something with the RR speed sensor. They can cause all kinds of problems. I installed one without looking at the part number (looked like a duck walked like a duck) and I thought I had problems before installing.. To summarize I installed the proper wheel speed sensor with correct PN and all was well.

[ard]

Agree. Seems like a reasonable guess. Do all the other codes clear, and only the wheel speed sensor stuff stays?? (No real clear pattern in those...)

[740iS]

Pretty much. The ones that return most often are:

00604E RDC: RDC system
006057 RDC Wheel electronics, rear right
00A6f3 CCC-A: Coding data error
00E723 No message (condensation sensor,k 0x2D1) receiver integrated automatic heating
00E729 Message automatic air recirculation control sensor. 0x2D0, receiver integrated.

But the RDC system and RDC Wheel electronics, rear right are there every time. I am wondering if when I did my brake job a few months ago (August) and replaced the brake sensor if I somehow damaged the wiring for the ABS Sensor. Planning on taking the wheel off and inspecting this weekend.

[740iS]

Just to bring this one up to date, replaced the wheel speed sensor a couple of months back and turns out that wasn't the issue. The RDC issue was actually pointing at the TPMS system. Just replaced the right rear transceiver in the wheel well and the primary receiver of the frame rail under the drivers door.

But in all honesty (as it will take me a bit to get it tested thoroughly) I'm not certain this will fully resolve the issue. Reason I say, is this generation of TPMS system seems to be known for breaking down or simply put, being a piece of crap! Plus it looks like the primary receiver has been replaced before too. So I'll have to wait and see.

I'd love to program this system off and use FTM instead. I've seen the programming instructions using software I don't have. So I have to figure it out in ISTA D/P and see if I can make that change.