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RevGTO
April 29th, 2009, 03:22 PM
I've been running LT's for a couple of years now with occasional codes. Lately, they have been popping up every day or two. I tried a new Denso and swapped it from side to side, but if anything, it was worse than the stockers. My fuel trims are fairly high, my exhaust smells rich, and my mileage is crappy.

Three questions:
1. Would lowering the O2 switch points possibly help?
2. In order to run OLMAF, do I have have to do anything besides raise the CL temp enable (B4205) and disable fuel trims (B3801)? My cat protection (B0701) is already off.
3. Is editing the B3605 OL Commanded Fuel advisable?

Thanks for any guidance.
The Alchemist
May 6th, 2009, 07:58 PM
http://forum.efilive.com/showthread.php?t=9932
try this.......
Its all about heat/temperature of the O2 sensor

top secret though don't tell anyone :secret:
Very very common problem with fitting Long tube headers and big bore exhausts. Just google it :)
We had a customer a couple of years ago referred from another workshop with this exact problem after THEY had fitted 2 sets of new o2 sensors after a new exhuast > opps. We actually got the new o2's to fire up after a few hard km's to get some heat into them. Fit the lower ohm bosch universal replacements problem fixed. Customer happy!
Mike
RevGTO
May 9th, 2009, 02:41 PM
What ones are 2-4 ohms? A lot of guys on LS1tech have used Bosch 13111 rear Corvette sensors on the theory that the rears are hotter, and have had poor results. I did the same with a Denso rear it was no help.

My question was about tuning because I've come to the conclusion that these O2's just aren't going to work - regardless of brand/type.
mr.prick
May 9th, 2009, 02:51 PM
Why not set the DTC to no mil?
RevGTO
May 10th, 2009, 11:58 AM
Because the real problem is not that it's throwing codes, it's that fueling isn't right because the O2's aren't doing their job properly.

Wish I could get some "feedback" on my tuning questions ...
mr.prick
May 10th, 2009, 01:56 PM
Is COT on?
Any DTC's?
The Alchemist
May 10th, 2009, 07:32 PM
What ones are 2-4 ohms? A lot of guys on LS1tech have used Bosch 13111 rear Corvette sensors on the theory that the rears are hotter, and have had poor results. I did the same with a Denso rear it was no help.

My question was about tuning because I've come to the conclusion that these O2's just aren't going to work - regardless of brand/type.

http://forum.efilive.com/showthread.php?t=10223

http://www.bosch.com.au/content/lang.../Section_C.pdf (http://www.bosch.com.au/content/language1/downloads/Section_C.pdf)
page 31 about 3/4 the way down the page
P/N 0-258-965-505
its on this post....
Cheers,
Mike
RevGTO
May 11th, 2009, 02:09 PM
Is COT on?
Any DTC's?COT is off. Just now I pulled two P0135 low voltage codes on Bank 1 from the car. That's my most common one - I get it sometimes on Bank 2 also. I get most of the O2 related codes at one time or another. I set the DTC's for "insufficient switching" (1133 & 1153) to noMIL.

This was an occasional issue until I installed a better flowing I-pipe and muffler. Neither the Y-pipe or anything near the O2's was touched. But the pace of the codes really picked up.
RevGTO
May 11th, 2009, 02:20 PM
P/N 0-258-965-505
its on this post....
Cheers,
MikeThat P/N is not on that page, or elsewhere in the catalog as far as I can tell. There is a 258-986-505. Would that be it?
The Alchemist
May 12th, 2009, 08:26 PM
what was I thinking ! .......yes its 986 not 965
0-258-986-505 its an 18w heater instead of the standard 12W heater....
Give them a go, they'll work a treat...
Still top secret though :secret:
Thanks :)
RevGTO
May 13th, 2009, 12:46 AM
Ok, I'll pony up the cash and give this a shot. If this doesn't work, it's OLMAF for sure.
RevGTO
May 13th, 2009, 03:04 PM
I found out today that you can't find anything with dealers with that part #, as it's the internal Bosch number. Did some intensive googling tonight and found the store number.

Any tips on mating the wires as I'll be splicing it with a connector from an extension? I'm also going to try one side first before I invest in both.
mr.prick
May 13th, 2009, 03:39 PM
http://forum.efilive.com/showpost.php?p=20320&postcount=66
5361
The Alchemist
May 13th, 2009, 09:44 PM
I found out today that you can't find anything with dealers with that part #, as it's the internal Bosch number. Did some intensive googling tonight and found the store number.

Any tips on mating the wires as I'll be splicing it with a connector from an extension? I'm also going to try one side first before I invest in both.

inside the box it comes with full wiring info....its really straight foward. It also has the splicing plug and connectors to the job. Very tidy and better than using crimps :)
RevGTO
May 13th, 2009, 11:48 PM
Yep, on one of the Bosch pdf's they had installation instructions and the kit appears very well thought out. Hopefully I'll find one locally today and get installed by the weekend.

Thanks to you guys for the help so far and I'll update after the install.
joecar
May 14th, 2009, 03:17 AM
Can you please post that pdf.
RevGTO
May 14th, 2009, 10:03 AM
http://www.bosch.com.au/content/language1/downloads/Section_A.pdf

Installation instructions are on page 28.
RevGTO
May 15th, 2009, 05:43 AM
Ok, after searching on the internet, I found info that indicated Bosch part # 0-258-986-505 corresponded to a shelf part # of 15738. This is the one I ordered. The instructions that came with it showed it to have two heater wires, one signal wire and a ground. Yet as pictured above in the post by Mr. Prick, the GM four prong connector has two signal connections, one heater, and one ground. Is 15738 the right sensor? If so, how do you wire it?

I found a local Bosch expert who searched his current parts books and could not find any reference to that original part number. He said it may have been superceded but there is not reference to that original number.

Further help anyone?
ssvolvo
May 24th, 2009, 07:10 AM
As with ANY Bosch 4 wire sensor. The two white wires are the heater power and ground....either white will work.

The black is sensor voltage 0-1 volt and the gray is sensor ground.

John
RevGTO
May 24th, 2009, 03:32 PM
Thanks. I've gotten more info from PM's corroborating what you say. It should wire up ok, and it tested to 2.6 ohms meaning that it is the hotter 18w type.

I've been out of town, but I should get it wired up some time this week and report back.
RevGTO
May 30th, 2009, 04:11 PM
Well, I got it wired up on Friday and installed it. Threw insufficient activity and low heater function codes after a day. Scanned and it showed no activity on that sensor.

I wired the two white wires to C & D (heater power and ground), black to B (signal high) and gray to A (signal low) - according to the image in the post by Mr. Prick above.

I pulled it tonight and re-checked my connections. Any other ideas?
The Alchemist
May 31st, 2009, 06:18 PM
:nixweiss:
So you have a good power supply on the heater power wire??? A good earth?
When you scan the o2voltage with efilive does it show any activity at all of just sit on 450mv. Bearing in mind the ecu sends a base 450mv on that sensor high line with very low amps until the o2 starts switching and overrides it......with its own stronger signal
RevGTO
June 1st, 2009, 03:32 PM
No, no activity when I scan. I drove it around and the bank 2 sensor was switching but the bank 1 sat on 447mv or something like that.

Stock sensor was switching and so is the Denso I have in there now.

I redid the connections on one side ... they appeared fine but I checked them and redid them anyway. When I get around to it, I'll reinstall and test.

If it's still dead, that must mean it's wired wrong. Or that this particular sensor is not compatible with my car ... but if it's four wire, it should be compatible, right?
ssvolvo
June 1st, 2009, 08:41 PM
Check the for open/shorted wiring ALL THE WAY BACK to the ECM.
RevGTO
June 3rd, 2009, 12:21 PM
Check the for open/shorted wiring ALL THE WAY BACK to the ECM.Like I said, I have a Denso sensor in there now and it is working (throwing code for insufficient switching, but working). The problem is clearly with the Bosch sensor wiring.
The Alchemist
June 7th, 2009, 08:33 AM
yes it sounds like the wiring to me... as I run them in cars here in NZ and they work fine > Mike



Like I said, I have a Denso sensor in there now and it is working (throwing code for insufficient switching, but working). The problem is clearly with the Bosch sensor wiring.
RevGTO
June 7th, 2009, 10:07 AM
Funny you'd post right at this moment ... I redid my connections, tested for conductivity, and reinstalled it just a little while ago. No activity. As I posted above, I connected the two whites to C&D, the black to B, and the gray to A as directed in the post by ssvolvo.

Somehow this isn't right but there's no way of knowing now besides randomly swapping the connections around. I just can't find any information about it over here; talking to Bosch has been a joke.