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oxygen sensor

dammit32

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Hey - havent been on for a while but its good to see the site is doing well.

I had my K5 parked for a little while so i could use the commuter car. When I started driving it ...it seemed to sputter some and has a little bit of a hard time on hills.

I'm taking a stab in the dark that its the oxygen sensor. I'd like to know if there is a way to test it.

money is slim here so I dont wanna buy it and be wrong.

any feedback is GOOD feedback

i did a search and didnt find much

thanks in advance
 
If it's a factory TBI engine a bad O2 sensor will not cause the engine to run poorly. The ECU uses the O2 sensor to adjust fuel levels to optimize fuel economy. Usually the only ill effect of a bad o2 sensor is decreased fuel economy. If cash is tight, don't waste it on an O2 sensor.

I would first check/change the fuel filter. Dump the gas out from the fuel filter and look for rust and water. It may be as simple as a new filter and fresh tank of fuel.
 
x2 with what loafer said. One of the draw-backs with electric fuel pumps is they don't like sitting for long periods of time, without being used.
 
so i forgot to mention the Check engine light came on and then went off while i was driving.:confused:
 
First thing you need to do is take it out of your bung hole! sorry, I could'nt resist that one. I think any big parts store chain can test it. call 'em.
 
My '87 K5 blew a 02 sensor completely out. It turned on CEL often for short periods an turned off again. 5 minutes to replace an run correct again. Check em out.
 
loafer said:
If it's a factory TBI engine a bad O2 sensor will not cause the engine to run poorly. The ECU uses the O2 sensor to adjust fuel levels to optimize fuel economy. Usually the only ill effect of a bad o2 sensor is decreased fuel economy. If cash is tight, don't waste it on an O2 sensor.

I would first check/change the fuel filter. Dump the gas out from the fuel filter and look for rust and water. It may be as simple as a new filter and fresh tank of fuel.
?? its not JUST fuel economy. It uses it to decide how much fuel to send when. Thats not a function of fuel economy but any running engine... The O2 sensor is one part of the puzzle of fuel injection. Granted TBI doesn't look at the O2 sensor as heavily as most newer OBDII systems, but it is still an engine input device and still necessary for proper engine operation.

If a O2 sensor being bad won't effect performance then how does a 3 wire O2 sensor improve performance in engines with headers? My 89 Suburban ran like piss when it was cold. It would spit and sputter when you jumped on it, and just run like total dog **** over all. I installed a 3 wire O2 sensor, and it ran like raped ape.
 
sled_dog said:
?? its not JUST fuel economy. It uses it to decide how much fuel to send when. Thats not a function of fuel economy but any running engine... The O2 sensor is one part of the puzzle of fuel injection. Granted TBI doesn't look at the O2 sensor as heavily as most newer OBDII systems, but it is still an engine input device and still necessary for proper engine operation.

The O2 sensor is used for running closed loop only, which means it's opperating in feed-back control mode with the O2 sensor providing the feedback. The o2 sensor only modifies the base value to the fuel table to opperate at a perfect stoicemetric mixture. It does not determine the fuel values.

When the engine is cold, or when it is under high loads the ECU switches out of closed loop and runs open-loop, ignoring the sensor(s) all together because in these conditions the engines needs to opperate slightly rich or outside the opperating range of the sensor (rich @ WOT).

sled_dog said:
If an O2 sensor being bad won't effect performance then how does a 3 wire O2 sensor improve performance in engines with headers? My 89 Suburban ran like piss when it was cold. It would spit and sputter when you jumped on it, and just run like total dog **** over all. I installed a 3 wire O2 sensor, and it ran like raped ape.

O2 sensors require an opperating temperature of at least 600F to function. If you use headers the sensor is mounted in the collector and the EGT is too cold at that point to heat up a single wire sensor. This is why a heated o2 sensor (3 or 4 wire) is used. I run a 3-wire O2 sensor on my header equiped blazer for this reason. All newer vehicles use heated sensors becaue it heats up the sensors faster, which means the engine can enter closed loop sooner, reducing fuel consumption and reduce emissions.

The 88 350 TBI I had would run fine with the 02 sensor unplugged completely. Our 91 caravan is the same way; unplug the sensor and it is fine. Of course the check engine light comes on and the fuel economy drops, but that's it.

I should also add that depending on how the engine is tuned a bad sensor can cause a rough idle. But usually it just causes the engine to run rich.
 
dammit32 said:
I checked the codes and got a 22 tps voltage low

that makes a lot more sense than the o2 sensor being bad. check your wires going to the TPS before buying a new one, because more than jsut a bad sensor will cause that code to be thrown as in a broken wire
 
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