Are Bosch o2 sensors really this bad?

Status
Not open for further replies.
C

Chris142

Joined
Jun 5, 2003
Messages
28,028
Location
Apple Valley, California
Gas milage in my Jeep has been declining. No codes thrown but with 110K on it I figured the 02's were due anyway. Called Napa and they sent the direct fit ones over. I put them in Monday night.

This morning I got a CEL. PO135 which is a 02 code.

I've never had an 02 code untill I put the Bosch 02's in.

Napa sent me a replacement for the one that threw a code and I just put it in and sent the other back as a defective.

Thoughts?
 
Last edited:
Bosch sensors are all I use and haven't had any problems
21.gif
 
Their sensors are fine. Are you sure they gave you the right part numbers? Bosch O2 sensors are OEM on tons of cars. It's one of their core products.
 
I think P0135 is for the sensor heater circuit. Check the connector and the resistance on the heater lead. Compare to the old one if it's still around.

There's a lot of hatred on the Internet for Bosch O2 sensors--especially in Mopar circles--but I haven't seen any real data to support it. I once used a non-heated Bosch in a turbo K-car and it was fine.
 
I've only used one and it has to be the cause of the lesser mpg. Both my dads Festiva's are 91's. The one with the bosch is the stripper model no ac nothing. The other has the ac and all the goodies. The one with all the goodies always gets 5+ mpg better and it's the heavier of the two. I maintain both and that's the only difference, right down to the spark plugs - timing - fuel filters everything. If I remember it'll be swapped out when I change the water pump. Granted it could be anything could be eating my words..
 
If you got a planar sensor and the application calls for a non-planar sensor, or vice-versa, it would cause this problem because the heater in a planar sensor has a lower resistance. The planar sensors are designed to heat up faster.
 
brian - Sounds about right. In other words, the Bosch sensors were not bad, just not an exact/specific type that the car needed.
 
it could be giving slightly different voltages than OEM or defective, or wrong part. i used NGK or NTK O2s last change from summit and they seem to be good
 
Originally Posted By: dparm
Are you sure they gave you the right part numbers?
According to NAPA's site and their catalog these are correct for the Jeep. They are not interchangable so it's not like I accidentally swapped em.
 
Sometimes parts are bad out of the box. Did the replacement work? If that one is defective too, then time to look for another brand.

I have a Bosch unit in my Jeep and its been fine for the last 10,000+ miles, though it is different than the one in your application. (The 87-90 Jeep Cherokees use a Renix system (short for Renault and Bendix) before Chrysler injection systems were used in later models).
 
Bosch O2 sensors for Chrysler applications have a horrible track record. This is pure hearsay, but I've heard that Bosch outsources manufacturing for some of their aftermarket product lines, so the quality can vary hugely from one application to another.

Never had any problems whatsoever with NGK O2 sensors in Chrysler/Jeep applications.
 
Originally Posted By: 440Magnum
Bosch O2 sensors for Chrysler applications have a horrible track record. This is pure hearsay, but I've heard that Bosch outsources manufacturing for some of their aftermarket product lines, so the quality can vary hugely from one application to another.

Never had any problems whatsoever with NGK O2 sensors in Chrysler/Jeep applications.

+1
thumbsup2.gif


I would buy Bosch oil filters but not O2 or Sparkplugs as I haven't had any luck with them.

Other parts made by Bosch for my '89 Cabriolet are of very high quality and I have purchased them. (Mechanical Fuel injectors, Warm-Up Regulator)

I just feel their product quality isn't consistent over their product line and that is sad.
frown.gif
 
I don't believe this is necessarily the case here but I would never trust NAPA or any of the chains on part numbers, I've seen multiple issues where their computer (and I presume they all use the same database) have been completely wrong for my truck on sensor part numbers.

An example was coolant temp sensors, for which every chain I went to (NAPA, AAP, PB, etc) had the same part number for both when in fact they were NOT the same part (or part number). Had to suck it up and head to the dealer who confirmed the different part numbers.
 
From a true cold start, 50 miles should be enough. It depends on how many miles are with each single event.
 
Originally Posted By: cchase
I don't believe this is necessarily the case here but I would never trust NAPA or any of the chains on part numbers, I've seen multiple issues where their computer (and I presume they all use the same database) have been completely wrong for my truck on sensor part numbers.

An example was coolant temp sensors, for which every chain I went to (NAPA, AAP, PB, etc) had the same part number for both when in fact they were NOT the same part (or part number). Had to suck it up and head to the dealer who confirmed the different part numbers.


More than likely some inept parts people thinking that a coolant temperature sensor and a coolant temperature sending unit or simply temperature sending unit were the same thing. From memory, I think your coolant temp sensor (for the computer) is a WT3000 (BWD part number) and the one for the gauge is a WT3024, though I am prone to bouts of CRS
lol.gif
. The computers CAN and WILL be wrong on occasion (such as with Toyota AC parts), but the mantra to remember is this: when in doubt, get the book out.

Bosch O2 sensors are a mixed bag: some work splendidly and some are [censored] right out of the box. Best thing to do is to go with OEM if there is a doubt about compatibility, which Denso, NGK, and Bosch make the vast majority of.
 
Originally Posted By: Chris142
Originally Posted By: MNgopher
Did the replacement work?

It's too early to tell. It took about 50 miles for the light to come on with the other one.


Most emissions DTC's will set within 2 to 3 drive cycles, depending on the manufacturer.
 
Status
Not open for further replies.

Similar threads

blaze2051
97 4x4 5.9L dodge ram O2 sensor B1S2
Replies
7
Views
449
clinebarger
Globalksp
Helping our Babysitter: Diagnosing from 14(!!!) Engine Codes 2012 Hyundai Velostar
2
Replies
29
Views
1K
Accent Abuser
JeffKeryk
2001 Tundra P0135 - O2 Sensor
Replies
7
Views
941
meep
JeffKeryk
Stupid Oxygen Sensor Question - Replace in pairs?
Replies
18
Views
4K
edyvw
GMBoy
Quick Lube Strikes Again!
2 3 4
Replies
65
Views
4K
OVERKILL
Back
Top