P0134, P0137, Or P1132

[volvo driver 2]

1999 Volvo S70T5 numerous check engine lights; the codes changed from no activity to low voltage (either front or back 02 sensor) on standard OBD2 testers (several types) sometimes MAF sensor (P1132). Removed and replaced both 02 sensors ($560+) same results (Volvo had also changed these sensors). Also on hot days or in traffic the idle would get rough and exhaust would develop black smoke and this was intermittent and never repeated when dealer would take their short test drives.

I found an automotive accessory dealer with a very expensive tester: we plugged it in and in manual sensor testing it showed that the problem was the ambient temp sensor (in manifold) was bad it showed -39 degrees, thus engine was running very rich causing O2 sensors too send wrong information). Tester had built in printer; I took the item that it said was bad to Volvo and for $49 dollars purchased a new one and in Volvo parking lot replaced the sensor (no tools required). “Wow” no problems check engine light stays off-no codes and it passed smog check (all sensors within limits).

Moral to this story = Standard OBD testers may not tell the whole story. Find a tester that the professionals use (cost me a bundle to,learn this), but once I found reputable dealer that actually knows how to use the test equipment (no charge for the testing)–and not not just the standard tests that indicate O2 sensors) we tested all sensors and found and fixed the problem!

[CHARGER69O1]

1999 Volvo S70T5 numerous check engine lights; the codes changed from no activity to low voltage (either front or back 02 sensor) on standard OBD2 testers (several types) sometimes MAF sensor (P1132). Removed and replaced both 02 sensors ($560+) same results (Volvo had also changed these sensors). Also on hot days or in traffic the idle would get rough and exhaust would develop black smoke and this was intermittent and never repeated when dealer would take their short test drives.

I found an automotive accessory dealer with a very expensive tester: we plugged it in and in manual sensor testing it showed that the problem was the ambient temp sensor (in manifold) was bad it showed -39 degrees, thus engine was running very rich causing O2 sensors too send wrong information). Tester had built in printer; I took the item that it said was bad to Volvo and for $49 dollars purchased a new one and in Volvo parking lot replaced the sensor (no tools required). “Wow” no problems check engine light stays off-no codes and it passed smog check (all sensors within limits).

Moral to this story = Standard OBD testers may not tell the whole story. Find a tester that the professionals use (cost me a bundle to,learn this), but once I found reputable dealer that actually knows how to use the test equipment (no charge for the testing)–and not not just the standard tests that indicate O2 sensors) we tested all sensors and found and fixed the problem!

This is why some would say that a professional shop or a dealer is well worth the money. They will actually save you from spending a "bundle" on useless repairs. If you find one with a good rep and cannot do the work yourself..stick with them, it will save money in the long run.

[flyfishing3]

This is why some would say that a professional shop or a dealer is well worth the money. They will actually save you from spending a "bundle" on useless repairs. If you find one with a good rep and cannot do the work yourself..stick with them, it will save money in the long run.

agreed. i do as much as possible but i'm not afraid to bring the big boys in to pin point something specific. there is only one mast. volvo tech who touchs my car. we have a good relationship and he lets me hang in his bay to watch and learn(he is supposed to but he knows i'm just trying to learn).

[Guest ALLAN]

1999 Volvo S70T5 numerous check engine lights; the codes changed from no activity to low voltage (either front or back 02 sensor) on standard OBD2 testers (several types) sometimes MAF sensor (P1132). Removed and replaced both 02 sensors ($560+) same results (Volvo had also changed these sensors). Also on hot days or in traffic the idle would get rough and exhaust would develop black smoke and this was intermittent and never repeated when dealer would take their short test drives.

I found an automotive accessory dealer with a very expensive tester: we plugged it in and in manual sensor testing it showed that the problem was the ambient temp sensor (in manifold) was bad it showed -39 degrees, thus engine was running very rich causing O2 sensors too send wrong information). Tester had built in printer; I took the item that it said was bad to Volvo and for $49 dollars purchased a new one and in Volvo parking lot replaced the sensor (no tools required). “Wow” no problems check engine light stays off-no codes and it passed smog check (all sensors within limits).

Moral to this story = Standard OBD testers may not tell the whole story. Find a tester that the professionals use (cost me a bundle to,learn this), but once I found reputable dealer that actually knows how to use the test equipment (no charge for the testing)–and not not just the standard tests that indicate O2 sensors) we tested all sensors and found and fixed the problem!