Help with P1119 - I'm now officially lost... (long)

[tarh33l]

For the last few months, I've been tracking down some gremlins in my '00 986. My check engine light has been on for a very long time. While still under warranty, I had it fixed again and again, each time the dealer telling me it was a faulty O2 sensor (and each time, the light would inevitably go back on, eventually tiring me of this to the point where I stopped going back to the dealer). Now that I'm out of warranty and I need to pass my emissions test, I've been trying to resolve this issue myself. I'm at the point where I really need some expert opinion. I'd really rather not go to the dealer, especially considering that I think I've gotten pretty far on tracking this down. Here's a brief history:

- In May, I broke down and bought an Actron 9135. Codes read: P1128 and P1130

- After weeks of clearing codes and driving, nothing was getting better

- Eventually, I started getting P1119, P0150, and P1133

- After looking on PPBB and renntech.org, I solved P1128 and P1130 by tightening a number of loose intake valves

- On to P1119 et al

- To ensure that this wasn't a faulty bank 2, pre cat sensor, I swapped the bank 1 and bank 2 sensors. No dice, still got P0150

- Finally got off my butt and bought a multi-meter. Tracked down a short which seemingly was causing P0150 and P0133

- Now, I only get P1119 (before, I was getting P1119 and P0150 fairly quickly after clearing codes, so at this point, I'm convinced P0150 is solved)

- I tested resistance on two pins (don't know which ones, but read that I should do this on PPBB) on the bank 2 pre cat sensor, and got a reading of 6ohms (warm). I thought I would get a reading of 0 ohms, and realize that the heating circuit was bad

Anyway, I'm about at the point where I'm thinking of taking it in (although I really don't want to). I'm not exactly sure where I go from there. P1119 is supposedly a heating issue in the pre-cat O2 sensor (and I don't even understand the sensor heating concept). However, there are about 5 different reasons listed in the Bentley manual as to why this code would be thrown. I've looked around and have found almost no references to P1119. Someone on PPBB suggested that I check the heater circuit relay (which I would assume is in the DME). If this were the case, wouldn't I be getting a "P" code for bank 1? If not, how would I go about testing this relay?

That's about it. Any help would really be appreciated. Please keep in mind, I am not overly comfortable testing electronics on my car (I'm an idiot when it comes to this stuff). So, if you have any suggestions about electrical testing, can you dumb it down for me? Thanks for any help.

Terence

[Loren]

Clear the final code and wait and see if your CEL comes on again. Many times P1119 triggers based on other faults - but it is not a fault by itself. Per the Porsche OBD II manual "This non-shedded fault is not an actual fault."

[tarh33l]

I've cleared the code about 4 times (once by disconnecting the battery for about 20 mins), the others by using the clear function on my OBD reader. Is there some other way I should be doing this? One thing I did note is that I get a pending P1119 immediately after clearing, pulling the key from ignition, and restarting. In the past (when I was getting P0150 and such), I wasn't getting P1119 as pending until those were pending as well (which often took some driving time).

Clear the final code and wait and see if your CEL comes on again. Many times P1119 triggers based on other faults - but it is not a fault by itself. Per the Porsche OBD II manual "This non-shedded fault is not an actual fault."

Edited July 31, 2006 by tarh33l

[Loren]

Do you get a CEL?

If not, I would ignore it.

[tarh33l]

Sorry, I should have made that more clear. I get the pending code until I restart the car. After about 3 miles or so, the CEL does indeed come on. Thanks...

Terence

Do you get a CEL?

If not, I would ignore it.

[Loren]

If it is (P1119) heating in the pre-cat O2 sensor then either that sensor is bad or the connector is bad or the wiring is damaged.

[tarh33l]

I guess this is where I need the most help. I wouldn't think it's the sensor since I've already swapped with the bank 1 pre-cat sensor, and am still getting the same code. Is there an easy way I can test if it's the connector? I've checked for resistance on both the connector and the plug, and I believe I'm getting the correct readings. If it's the wiring, is there an easy test (and, do I need to test anything in the DME like a relay or something)? Also, it appears that replacing this wiring would be quite complex. If it's not a DIY, I'll be more than happy to take it to the dealer.

Thanks for the help Loren. I appreciate your patience.

If it is (P1119) heating in the pre-cat O2 sensor then either that sensor is bad or the connector is bad or the wiring is damaged.

[Loren]

P1119 Oxygen Sensor Heating 2 Ahead of Catalytic Converter - Below Lower Limit

Check resistance of H025 heating.

1. Remove connector of H02S 1/2 ahead of catalytic converter.

2. Connect ohmmeter on pin side to pins 1 and 2.

Display: 1.8 - 2.5 ohms at 20°C.

3. Connect ohmmeter on pin side to pin 1 and H02S housing.

Display: infinite ohms

Check wiring from DME control module to disconnection point of H025 1/2 for continuity, short to B+ and short to ground.

1. Remove connector of H02S 1 and 2 ahead of catalytic converter.

2. Connect special tool 9616 to wiring harness (DME control module connector). This special harness tool keeps you from shorting the wrong wires on the DME and blowing the DME up. If you don't feel comfortable doing this then please have a shop or dealer do it. Last time I checked DME's were about just over $1000.

3. Connect ohmmeter to special tool 9616, pin 30, and disconnection point of H02S 1/2 ahead of catalytic converter, pin 2.

Display: < 1 ohms

4. Connect ohmmeter at sleeve to connector, pin 2, and ground.

Display: infinite ohms

5. Remove ignition, injection and oxygen sensor heating relay and bridge terminals 30 and 87.

6. Connect voltmeter at sleeve to connector, pin 2, and ground.

Display: 0 (zero) volts

Check output stage of DME control module.

1. Remove connectors to oxygen sensors.

2. Start engine and run at high speed for 3 minutes.

3. Connect voltmeter at sleeve to pin 1 (positive) and pin 2.

Display: battery voltage

[tarh33l]

Wow Loren! Thanks for the great information. Looks like I'll be busy over the weekend. I will be sure to post my results for the group.

Terence

P1119 Oxygen Sensor Heating 2 Ahead of Catalytic Converter - Below Lower Limit

Check resistance of H025 heating.

1. Remove connector of H02S 1/2 ahead of catalytic converter.

2. Connect ohmmeter on pin side to pins 1 and 2.

Display: 1.8 - 2.5 ohms at 20°C.

3. Connect ohmmeter on pin side to pin 1 and H02S housing.

Display: infinite ohms

Check wiring from DME control module to disconnection point of H025 1/2 for continuity, short to B+ and short to ground.

1. Remove connector of H02S 1 and 2 ahead of catalytic converter.

2. Connect special tool 9616 to wiring harness (DME control module connector). This special harness tool keeps you from shorting the wrong wires on the DME and blowing the DME up. If you don't feel comfortable doing this then please have a shop or dealer do it. Last time I checked DME's were about just over $1000.

3. Connect ohmmeter to special tool 9616, pin 30, and disconnection point of H02S 1/2 ahead of catalytic converter, pin 2.

Display: < 1 ohms

4. Connect ohmmeter at sleeve to connector, pin 2, and ground.

Display: infinite ohms

5. Remove ignition, injection and oxygen sensor heating relay and bridge terminals 30 and 87.

6. Connect voltmeter at sleeve to connector, pin 2, and ground.

Display: 0 (zero) volts

Check output stage of DME control module.

1. Remove connectors to oxygen sensors.

2. Start engine and run at high speed for 3 minutes.

3. Connect voltmeter at sleeve to pin 1 (positive) and pin 2.

Display: battery voltage

[tarh33l]

Actually, Loren (or anyone else for that matter), do you have any pics of the connectors you're referring to in this post (I've got the Bentley manual at home, so if they're in there let me know and I can dig them up myself)? I really don't want to get this wrong. Also, I'm assuming when you use tool 9616, you're only concerned about shorting out the DME when you're applying voltage (do I need to worry about this when I'm checking resistance only?).

Terence

P1119 Oxygen Sensor Heating 2 Ahead of Catalytic Converter - Below Lower Limit

Check resistance of H025 heating.

1. Remove connector of H02S 1/2 ahead of catalytic converter.

2. Connect ohmmeter on pin side to pins 1 and 2.

Display: 1.8 - 2.5 ohms at 20°C.

3. Connect ohmmeter on pin side to pin 1 and H02S housing.

Display: infinite ohms

Check wiring from DME control module to disconnection point of H025 1/2 for continuity, short to B+ and short to ground.

1. Remove connector of H02S 1 and 2 ahead of catalytic converter.

2. Connect special tool 9616 to wiring harness (DME control module connector). This special harness tool keeps you from shorting the wrong wires on the DME and blowing the DME up. If you don't feel comfortable doing this then please have a shop or dealer do it. Last time I checked DME's were about just over $1000.

3. Connect ohmmeter to special tool 9616, pin 30, and disconnection point of H02S 1/2 ahead of catalytic converter, pin 2.

Display: < 1 ohms

4. Connect ohmmeter at sleeve to connector, pin 2, and ground.

Display: infinite ohms

5. Remove ignition, injection and oxygen sensor heating relay and bridge terminals 30 and 87.

6. Connect voltmeter at sleeve to connector, pin 2, and ground.

Display: 0 (zero) volts

Check output stage of DME control module.

1. Remove connectors to oxygen sensors.

2. Start engine and run at high speed for 3 minutes.

3. Connect voltmeter at sleeve to pin 1 (positive) and pin 2.

Display: battery voltage