Is there actual shielding? The electrical tape in the photo prevents seeing whether the sleeve is a shielded sleeve (metal mesh lining) or just a sleeve (for convenience of identification of a wire cluster for a given purpose).

 

 

Yes, of course the signal wiring from air:fuel ratio sensors requires shielding. Knock sensor signal wires do also. The output signals have very little signal power and are susceptible to interference from wires caring more current that switch power on and off at times. That shielding must also be grounded to chassis ground - if not grounded, the shielding provides little benefit.

 

Thanks! good information. As crummy as the harness looks, someone must have chopped it up to expose the wires inside so I need to trace those 3 wires & re-wrap that bundle and see if it cures my on/off CEL issues. I appreciate the prompt reply! I have found no information anywhere on this issue (other than the miniscule graphic schematic. Any idea why they show a dotted line rectangle in two places for the shielding? Thus far I don't find 2 only the one...

 

What engine do you have? 4-cylinder or V6?

 

v6

 

Looks like you had that in your first post - I missed that. Sorry.

Can you post a photo of your wiring diagram involving your two knock sensors? The shielded wires you show a photo of don't match the wire colors in your air:fuel sensor wiring diagram. Just wondering if that particular group of shielded wires involve your two knock sensors.

 

I just unwrapped a major mess... if all that is what they did in the factory, I'd be ashamed...I unplugged all the plugs (behind the glovebox) and eventually re-plugged them. the exposed stainless wire is also touching the foil inner layer of the shielding insulation. So there's not 3 wires necessarily - there are two - black and white. however the stainless exposed wire does have its own socket in the plug and theres no continuity to ground on several body points I touched, so that's a relief... Upon cold start the data stream shows immediate CL both banks and after a 15 minute run, still no CEL. Data stream shows excellent numbers on short and long terms, both banks are very close to parallel and LAMBDA for both are .9999/1.000... as Ivan would say - the car is HAPPY... I ordered a better reader - a Blue Driver which will be here on Monday and I'll see what it comes up with. My current reader is a Think OBD 100 pretty basic but still not a bad buy at $20, 5 years ago... What I did see while every thing is unwrapped is there are quite a few shielded wires in the main harness coming thru the firewall on the passenger side most appear to have an exposed single wire heading to the plug, so now I need to figure out which are in the A/F heater circuit, but for now it seems that the "unplug/plug" operation may have scraped some invisible corrosion coating away...Hope floats!

 

One thing I always have on my shelf along with many other stuff is the essential spray cans:
Along with brake Cleaner, Battery cleaner, CRC MAF and CRC Throttle body and intake cleaner is a can of electrical contact cleaner. It's pretty much Isopropyl alcohol but in a spray can. Quick fix for many gremlins. Never use WD-40 for cleaning electrical contacts and switches though. If using plain isopropyl it's recommended to not use anything under 90%. It's actually surprising how a little bit of corrosion can cause some really annoying issues. Especially the intermittent gremlins. Scraping is normally a last case scenario as it can makes things worse.

 

You and me, Gary. After wrenching for more than 60 years, my supply store is pretty adequate as well...When I said "scraping" it was to describe the action made unavoidable by removing and reinserting these delicate multi-pin connectors. In many ways this Toyota is a pretty tough old bird... but in a technical sense, I do not even care to disturb a single pinfeather unnecessarily, lest she show me her ire and turn into a Phoenix on a pyre... Case in point: the day I sprayed the IAT sensor (tho it looked clean at the time) with CRC and on the road test, it ran like crapolla for the first time in my 3 year ownership...I was freaked out - especially later in the day watching the "Car Care Nut" say to NEVER clean that part! When viewing the codes, it had gathered about 4 new ones, mentioning random misfires and other previous roughness never experienced prior... The main culprit seemed to be the MAF, which cleaning later improved things... Needless to say, my lifelong habit of preventive maintenance vs. repair-after-the-event (ie "IF IT AIN'T BROKE, DON'T FIX IT!"). has slowed immensely. Bee-sides, I'd ruther be fishin' ennyways... But I appreciate the reply and info. It all helps.

 

I am having some similar issues was that wiring was by your ECM or under the hood?

 

It is from the ecm plugs. If you haven't tried this already, I suggest you disconnect your battery cables, unplug the connectors from the ecm, spray them and the ecm sockets with QD ELECTRONIC SPRAY CLEANER by CRC and let them dry and put them back in their sockets. See if that cures whatever strangeness you're having. I've been chasing odd issues with this Camry for months - intermittent, appearing, disappearing CEL, etc. I'm still a bit doubtful that the problem is cured but for several days since I sprayed everything down the light has not reappeared and my new Blue Driver did a complete scan today and showed no codes. good luck.

 

Thanks for that info!

 

Nice pic from the White River Sno-Park off Hwy 35! About mid-October, I'd say, from the snow contours on Hood. (My sister lives in Government Camp.)

 

Wow - I'm impressed with your observation ability! That's last year ('23) my gf was here from Asia. Had never touched snow in her 60 years and kept asking when we were going to find any...I watched the road cams each day until I saw a layer at Blue Box and said, "Let's go TODAY!" We found enough for her to lay in, play in, and take pics back with her when she left just a few days later. Amazing timing. This year was a repeat, except for coastal weather November nastiness...we found a blue hole in the sky that followed us around for a few days camping and after we returned to the high desert, it was steady downpours for a week at the Oregon coast.