Fixed Boost Leak Now "eng. Light "

[Phil94850]

ive had a bad boost leak on this car since i bought it. i fixed it ( the hose going to the throttle body had a tear in it ) now its boosting great but shortly after that my engine light came on. i have a MBC hooked up and after fixing the boost leak it was hitting like 16 and 17psi on stock ecu so i turned it down to around 12 to 14. anyways. The car has close to 200k on the engine, ive recently tuned it up plugs, wires, rotor, timing belt, ( but dizzy cap is old, they were out of stock at the time ), . i pulled the codes and they read as such..

522 & 153= o2 sensor

414=boost pressure regulation

543=misfire one cyl.

454=misfire cyl4

452=misfire cyl2

542=misfire more than one cyl.

231=TPS sporadic

315= evap system

sheww... with all that said.. since my boost leak was pretty bad, and i fixed it then it boosted kinda high would this cause these type of codes ? ever since then though.. ive noticed around 2k RPM the car wants to hesitate, this didnt start until after the eng. light came on. its worse as the car warms up. above 2k rpm... it pulls hard, it will break the tires loose. what do u guys think ?? thanks again for any help !!

[Phil94850]

after reading codes and resetting the check engine light now it feels like the car isnt hesitating anymore ??? could it be possible i was in "limp mode" ????

[AlvinL]

Yes. Did any codes return?

[T5BRICK]

Yup, reset your codes and see which ones come back. Actually, if you were running with a boost leak for a long time, you might want to reset your adaptives(disconnect the battery for 10 minutes). I don't think your O2 sensors or cat being messed up is too far fetched if you were running rich for a long time.

[MadeInJapan]

Yup, reset your codes and see which ones come back. Actually, if you were running with a boost leak for a long time, you might want to reset your adaptives(disconnect the battery for 10 minutes). I don't think your O2 sensors or cat being messed up is too far fetched if you were running rich for a long time.

+1 on resettting the adaptives. That's exactly what I was going to post, but you beat me to it.

[Phil94850]

oddly enough..my battery took a crap yesterday so i had to replace it anyways. ive driven around and no CEL yet. im gonna check and see if any codes have come back. thanks for everyones help !!

[Phil94850]

i ran my codes again and the only one that came back was 522&153= O2 sensor... does this mean my O2 is bad ? do i need to replace both ? also.. can you replace with the cheaper aftermarket brands ? these are 4 wire sensors correct ?

[AlvinL]

i ran my codes again and the only one that came back was 522&153= O2 sensor... does this mean my O2 is bad ? do i need to replace both ? also.. can you replace with the cheaper aftermarket brands ? these are 4 wire sensors correct ?

The codes are for the rear O2 sensor.

Code 1-5-3 (Rear HO2S Signal)

1) If Codes 5-2-2 or 2-1-2 are stored, perform diagnosis for these codes first. If fault is permanent or intermittent and signal is

too high, perform diagnosis as per Code2-1-2. If fault is permanent and signal is too low, go to next step. If fault is permanent and

signal is faulty, go to step 8). If fault is intermittent and signal is too low, go to step 9). If fault is intermittent and signal is faulty, go to step 10).

2) Turn ignition off. Wait 2 minutes. Disconnect rear HO2S Gray connector. Connect an ohmmeter between HO2S connector terminal

No. 4 and ground. If ohmmeter shows about 100 k/ohms, go to step 4). If ohmmeter shows infinite resistance, go to next step. If ohmmeter shows about zero ohms, check wiring between rear HO2S connector terminal No. 4 and ECM terminal A34 for a short circuit to ground.

3) Turn ignition off. Disconnect HO2S connector. Ensure ECM connector terminal contacts are clean and tight. Reconnect ECM.

Connect an ohmmeter between HO2S connector terminal No. 4 and ground. If ohmmeter reads about 100 k/ohms, source of code is poor contact at ECM connector. If ohmmeter does not read about 100 k/ohms, check wiring between rear HO2S connector terminal No. 4 and ECM terminal A34 for an open circuit.

4) Turn ignition off. Disconnect rear HO2S connector. Connect an ohmmeter between HO2S connector terminal No. 3 and ground. If

ohmmeter reads about 200 ohms, go to step 7). If ohmmeter shows infinite resistance, go to next step. If ohmmeter shows about zero

ohms, go to step 6).

5) Turn ignition off. Disconnect rear HO2S connector. Ensure ECM connector terminals are clean and tight. Reconnect ECM. Connect an

ohmmeter between HO2S connector terminal No. 3 and ground. If ohmmeter reads about 200 ohms, source of code is poor contact in ECM connector. If ohmmeter does not read about 200 ohms, check wiring between rear HO2S connector terminal No. 3 and ECM terminal A19 for an open circuit.

6) Turn ignition off. Disconnect rear HO2S connector. Disconnect front HO2S Black connector. Connect an ohmmeter between

rear HO2S connector terminal No. 3 and ground. If ohmmeter reads about 200 ohms, test system using a new front HO2S. If ohmmeter does not read about 200 ohms, check wiring between front HO2S connector terminal No. 3 and ECM terminal A33, and wiring between rear HO2S connector terminal No. 3 and ECM terminal A19 for a short to ground.

7) Turn ignition off. Ensure rear HO2S is connected. Start and run engine at idle. Check voltage at rear HO2S. Voltage signal

should have left its bottom setting (-.165 volt) and stabilized between .1-.9 volt within about 10 minutes. If reading is okay, source

of code is poor contact at rear HO2S connector. If reading is not okay, retest using new rear HO2S.

8) If fault is permanent and signal is faulty, turn ignition off. Wait about 2 minutes. Disconnect rear HO2S Gray connector.

Connect an ohmmeter between HO2S connector terminals No. 3 and 4. If ohmmeter reads infinite resistance, check wiring between rear HO2S connector terminal No. 4 and ECM connector terminal A34 for a short circuit to rear HO2S connector terminal No. 3 and ECM connector terminal A19. If ohmmeter does not read infinite resistance, test using new HO2S.

9) If fault is intermittent and signal is too low, check wiring between rear HO2S connector terminal No. 4 and ECM terminal

A34, and between rear HO2S connector terminal No. 3 and ECM terminal A19 for an open circuit. Check ECM and rear HO2S connector for loose connection. Check wiring between rear HO2S connector terminal No. 4 and ECM terminal A34 for an intermittent short circuit to ground. Also check wiring between front HO2S connector terminal No. 3 and ECM terminal A33, and wiring between rear HO2S connector terminal No. 3 and ECM terminal A19 for an intermittent short circuit to ground.

10) If fault is intermittent and signal is faulty, check wiring between rear HO2S connector terminal No. 4 and ECM connector

terminal A34 for an intermittent short circuit of wire between rear HO2S connector terminal No. 3 and ECM connector A19.

Code 5-2-2 (Rear HO2S Preheating)

1) Check status message using Volvo Scan Tool (998-8686). If PERMANENT FAULT, SIGNAL TOO HIGH is displayed, go to next step. If

PERMANENT FAULT, SIGNAL TOO LOW is displayed, go to step 3). If INTERMITTENT FAULT, SIGNAL TOO HIGH is displayed, go to step 8). If INTERMITTENT FAULT, SIGNAL TOO LOW is displayed, go to step 9).

2) If PERMANENT FAULT, SIGNAL TOO HIGH is displayed, turn ignition off. Disconnect front HO2S Black connector and/or rear HO2S

Gray connector. Turn ignition on. Connect voltmeter between HO2S connector terminal No. 2 and ground. If voltmeter reads about zero

volts, retest using new HO2S. If voltmeter does not read about zero volts, check wiring between HO2S connector terminal No. 2 and ECM

terminal A14 (Code 5-2-1) or terminal A29 (Code 5-2-2) for signs of a short circuit to voltage.

3) If PERMANENT FAULT, SIGNAL TOO LOW is displayed, turn ignition off. Disconnect front HO2S Black connector and/or rear HO2S

Gray connector. Turn ignition on. Connect voltmeter between HO2S connector terminal No. 1 and ground. If voltmeter reads battery

voltage, go to next step. If voltmeter does not read battery voltage, check wiring between HO2S connector terminal No. 1 and main relay

connector terminal No. 3 for an open circuit. 4) Turn ignition on. Disconnect HO2S connector. Connect voltmeter between HO2S connector terminal No. 2 and ground. If voltmeter reads about zero volts, go to next step. If voltmeter does not read about zero volts, check wiring between HO2S connector terminal No. 2 and ECM terminal A14 (Code 5-2-1) or terminal A29 (Code 5-2-2) for a short circuit to voltage.

5) Turn ignition off. Wait about 2 minutes. Disconnect HO2S connector. Disconnect ECM. Connect ohmmeter between HO2S connector

terminal No. 2 and ground. If ohmmeter reads infinite resistance, go to next step. If ohmmeter does not read infinite resistance, check

wiring between HO2S connector terminal No. 2 and ECM terminal A14 (Code 5-2-1) or terminal A29 (Code 5-2-2) for a short circuit to ground.

6) Turn ignition off. Disconnect HO2S and ECM connectors. Connect Breakout Box (981-3190) to ECM connector. Check all grounds.

See COMPUTERIZED ENGINE CONTROLS in I - SYSTEM/COMPONENT TESTS article. Connect an ohmmeter between HO2S connector terminal No. 2 and breakout box pin No. 14 (Code 5-2-1) or pin No. 29 (Code 5-2-2). If ohmmeter reads about zero ohms, go to next step. If ohmmeter does not read about zero ohms, check wiring between HO2S connector terminal No. 2 and ECM terminal A14 (Code 5-2-1) or terminal A29 (Code 5-2-2) for an open circuit.

7) Turn ignition off. Reconnect HO2S connector. Disconnect ECM connector. Connect ohmmeter between breakout box pins No. 27 and

No. 14 (Code 5-2-1) or No. 29 (Code 5-2-2). If ohmmeter reads 1.5-13 ohms, code is caused by poor contact in ECM and/or HO2S connector. If ohmmeter does not read 1.5-13 ohms, retest using new HO2S.

8) If INTERMITTENT FAULT, SIGNAL TOO HIGH is displayed, check wiring between HO2S connector terminal No. 2 and ECM terminal A14

(Code 5-2-1) or terminal A29 (Code 5-2-2) for an intermittent short circuit to voltage.

9) If INTERMITTENT FAULT, SIGNAL TOO LOW is displayed, check wiring between HO2S connector terminal No. 1 and main relay connector

terminal No. 3 for an intermittent open circuit. Check wiring between HO2S connector terminal No. 2 and ECM terminal A14 (Code 5-2-1) or terminal A29 (Code 5-2-2) for an intermittent open circuit or short circuit to ground. Also check HO2S and ECM connectors for loose

connection, contact resistance, and oxidation.