02 Tahoe died - no spark, no fuel

[JbJc64]

My wifes 02 Tahoe (Vortec V8) died at 60MPH, no hesitation prior. The night before it got a "service engine soon" light. Got it on a trailer and stopped to download code - had 2 codes, bank 2 sensor 1 oxy sensor heater malf, bank 2 sensor 2 heater malf. Got it home and has no spark (checked 2 different plugs) and cant hear fuel pump when I turn the key on. Checked fuses all are good. Read something about crankshaft sensor being bad could cause complete shutdown. I dont think the oxy sensors would shut it down. Any idea's?

[j cAT]

Originally Posted by JbJc64

My wifes 02 Tahoe (Vortec V8) died at 60MPH, no hesitation prior. The night before it got a "service engine soon" light. Got it on a trailer and stopped to download code - had 2 codes, bank 2 sensor 1 oxy sensor heater malf, bank 2 sensor 2 heater malf. Got it home and has no spark (checked 2 different plugs) and cant hear fuel pump when I turn the key on. Checked fuses all are good. Read something about crankshaft sensor being bad could cause complete shutdown. I dont think the oxy sensors would shut it down. Any idea's?

I would recheck fuses ALL with a volt meter....2 O2 sensors have heater malfunction....check exhaust cat area for O2 wire damage,,not routed correctly...bank 2 is passener side..

It is possible the crank sensor located under the starter is in need of examination....leads,resistance,debris on pick up,or the timing teeth ..wheel..

I have seen this before where at hyway speed the engine stops ....completely,,,then after cools down starts right up..

dtc showed a communication problem,,,but no mention of crank sensor, on the DTC.. It was a bad CPS,,,resistance very high...

when the key is first turned on the pump will run 2 seconds,,,,put the key to ignition on only no cranking,,,listen for pump...if no pump hit the bottom of the fuel tank...then repeat..

[JbJc64]

Thanks j Cat,
I did go back and check fuses again and found the ECMI 10amp fuse blown. Replaced it and it started fine, except I still have service engine soon lite.

Went to parts store and down loaded it again. "02 sensor bank 1 sensor 2 heater malfunction", cant put it together with ECMI fuse.

Parts store guy seems to think the 02 sensor not working overheated the exhuast due to bad sensor and shut down computer.

I cant seem to put a theory together. I plan on changing the sensor in the next couple days,now that I have the truck in the garage. Any suggestions as to a connection with the fuse and 02 sensor?

[j cAT]

Originally Posted by JbJc64

Thanks j Cat,
I did go back and check fuses again and found the ECMI 10amp fuse blown. Replaced it and it started fine, except I still have service engine soon lite.

Went to parts store and down loaded it again. "02 sensor bank 1 sensor 2 heater malfunction", cant put it together with ECMI fuse.

Parts store guy seems to think the 02 sensor not working overheated the exhuast due to bad sensor and shut down computer.

I cant seem to put a theory together. I plan on changing the sensor in the next couple days,now that I have the truck in the garage. Any suggestions as to a connection with the fuse and 02 sensor?

the ECM 1 fuse 10Amp circuit #15 is a feed to the pcm/vcm...this is why no start no fuel pump....check the fuse box to computer for wire damage and connector corrosion...

then if the vehicle has over 100,ooo mi on the O2 ,,,replace the O2 sensors and carefully inspect all for connector/wiring damage...also always re-install all wiring / connectors as built...this will prevent wire damage from exhaust...

with lower voltage going to a DC motor the motor will arc more, and run hotter,,,usually if you don't run the fuel down below 1/4 tank this pump will last 180,ooomi approx...fuel filter/relay must also be replaced at this time and make sure it is a delphi pump or you will do this repair 6-12 months from now..

next posting allways give the DTC failure codes,,,this will give better aid in determining the failure AREA....

[JbJc64]

Thanks again j Cat, I'm getting ready to pull the old 02 sensor, they tell me it is a connector type sensor so should connect back up same as factory type. I will check wiring and such before changing it.

You talked about the arcing more and hotter... I didnt follow you on that.

The code I got is P0141 left cylinder bank circut, heater performance

[j cAT]

Originally Posted by JbJc64

Thanks again j Cat, I'm getting ready to pull the old 02 sensor, they tell me it is a connector type sensor so should connect back up same as factory type. I will check wiring and such before changing it.

You talked about the arcing more and hotter... I didnt follow you on that.

The code I got is P0141 left cylinder bank circut, heater performance

the motor with lower voltages applied to it causes the motor to overheat ,,this is because the load on a fuel pump is constant, and with a lower than designed voltage will lack the proper amount of magnetic force to rotate the armature.....at the proper speed...heating then results...


the dtc 141 is most likely a defective O2 sensor,,,,but may be connector/wires.....the connectors must not be modified ,,,only use the proper connector types....[don't hack the wiring for fit]....

the pcm is not seeing a proper O2 feedback concerning the heater circuit...

[JbJc64]

I changed the 02 sensor, also checked all wiring for damage etc..all looks good. Cleared code and drove for several miles, all is good so far. Thanks for your help. My wife appreciates it also.

[j cAT]

Originally Posted by JbJc64

I changed the 02 sensor, also checked all wiring for damage etc..all looks good. Cleared code and drove for several miles, all is good so far. Thanks for your help. My wife appreciates it also.

your findings are normal, as the sensor is usually the problem on a vehicle that has had no exhaust/collision work...

remember these sensors are only good till 100,ooomi. after that the control/feedback to the pcm/computer is not correct ...the manufacturers all recommend this part be replaced at this interval...failure to replace at least the upstream sensors will result eventually in cat converter failure,,,this is expensive...as well as lower MPG/POWER.....

[JbJc64]

Changed the 02 sensor (bank1 Sensor 2) on Thurs night, drove for two days all is good. Sat morning the service engine soon light is back on. Downloaded code - P0141 02 sensor heater malf again. Not sure were to go next, could the catalytic convter be the problem?

[j cAT]

Originally Posted by JbJc64

Changed the 02 sensor (bank1 Sensor 2) on Thurs night, drove for two days all is good. Sat morning the service engine soon light is back on. Downloaded code - P0141 02 sensor heater malf again. Not sure were to go next, could the catalytic convter be the problem?

you replaced the o2 sensor and after a couple of days it returned,,,I would recheck the wiring and even check the pcm/computer connectors///as well as wires in the fuse box/under the fuse box....

bank 1 sensor 2 is the downstream sensor on the drivers side,,this is the one you replaced ?

the upstream sensors have how many miles on them,,,??? upstream sensor out of range could cause these problems

the first post you stated bank 2 passenger side failure O2 codes ....

this 141 code is generated by the pcm when it is not getting the correct feedback on cold start,,,the O2 sensor must give the proper variation of output in a certain time period..

after the engine is warmed this test is not repeated...so the cat converter will not throw this code,,,,

in every circuit you have a positive and negative path for current flow so both the supply side as well as the ground must be checked ///could be a bad corroded ground point/lug as well

[j cAT]

the other issue that was not addressed was ,,, why was the , ECM1 10AMP fuse blown ???? fuses don't just blow.....this could somehow be part of this ....

[JbJc64]

I did change the driver side sensor just aft of the cat converter, although the one they gave me as replacement was exact same connector and clips, but the actual sensor was alittle different. They assured me it was the correct one. I'm not sure it would give the exact same code if it was not the correct one and all other indications havent changed.

The first time I downloaded the codes I misread the the bank number, when I went back and checked them again they both read P0141, only the second one had a pending note on the OBD II scanner.

I agree on the fuse thing, I havent been convinced the o2 sensor caused the fuse to blow, I think you may be correct on the wiring. I will start tearing into the entire system tonight, starting at the fuse box and work my way back. I just checked connection wires etc.. last time

The light stayed off most of the day (driving to work and then lunch), then when I got in it to go home the end of the day came on with in 2 miles. The last time it came on was after cold start and less than 1 mile of driving.

I bought the truck used with 52K miles on it so would say they are original sensors, and I have not changed sensor 1 on bank 1 yet.

[j cAT]

Originally Posted by JbJc64

I did change the driver side sensor just aft of the cat converter, although the one they gave me as replacement was exact same connector and clips, but the actual sensor was alittle different. They assured me it was the correct one. I'm not sure it would give the exact same code if it was not the correct one and all other indications havent changed.

The first time I downloaded the codes I misread the the bank number, when I went back and checked them again they both read P0141, only the second one had a pending note on the OBD II scanner.

I agree on the fuse thing, I havent been convinced the o2 sensor caused the fuse to blow, I think you may be correct on the wiring. I will start tearing into the entire system tonight, starting at the fuse box and work my way back. I just checked connection wires etc.. last time

The light stayed off most of the day (driving to work and then lunch), then when I got in it to go home the end of the day came on with in 2 miles. The last time it came on was after cold start and less than 1 mile of driving.

I bought the truck used with 52K miles on it so would say they are original sensors, and I have not changed sensor 1 on bank 1 yet.

now I would swap the o2 sensors to see if it changes the dtc code,,,in addition to the wiring as I previously recommended..

[JbJc64]

j Cat, thanks again for your help. I took the fuse box up and checked all connectors and wire - all good. Checked computer connections and wires - good. went back under vehicle to left aft 02 sensor and checked all wires and connections - all good.

You saying change the pre converter 02 sensor on bank 1? Could the post converter I changed be bad? Same code as old one?

[j cAT]

Originally Posted by JbJc64

j Cat, thanks again for your help. I took the fuse box up and checked all connectors and wire - all good. Checked computer connections and wires - good. went back under vehicle to left aft 02 sensor and checked all wires and connections - all good.

You saying change the pre converter 02 sensor on bank 1? Could the post converter I changed be bad? Same code as old one?

swap the bank 1 with the bank 2 see if the code changes that way it rules out the O2 sensor///ya sometimes new is bad...

lets say it is not changing then it must be in the connectors/wiring...

were dealing with 350-700mv so it is a small signal voltage and must be with in this range..

also check all ground points in the engine compartment make sure clean and secure this is mentioned in the repair manual be sure the grounds are good...