jstolk2
Junior Member
- Joined
- Jan 28, 2015
- Posts
- 9
- Reaction score
- 0
- Location
- Iowa
- First Name
- Justin
- Truck Year
- 1983
- Truck Model
- K20
- Engine Size
- 350
Went with a buddy to look at a truck last night. 94 k1500 350TBI 144k miles, very solid. Has a power issue at low RPMs, but for the price, we figured what the hell. Runs very smooth, has not missed once. But as the motor gets up to operating temp, it gets very sluggish at low RPMs. We replaced cap, rotor, plugs, and wires already last night. The cap and rotor were in bad need of it. The plugs actually looked very good, but you could tell they were getting old. They were all dry. This did nothing for the problem. I put my OBD1 scanner on it, and it's giving a code 44 o2 sensor too lean code. I cant for the life of me find an o2 sensor anywhere. I'm guessing that it used to be in the y-pipe, but was just left out when new exhaust was put on. I also noticed the housing on the temp sensor by the thermostat is cracked. My questions I guess are these:
1. Will a TBI motor run okay without an O2 sensor? I'm assuming that however many thousand miles ago it was that they replaced the exhaust, it must have run okay afterwards. Otherwise they would have put one back in I would assume.
2. Would the bad temp sensor at the thermostat housing cause the motor to run too lean once warmed up? Seems logical to me. Any way of testing this sensor? The temp gauge seems to work great, but I'm assuming that it is tied directly to the sensor between 1 and 3 spark plugs.
3. I've read that TPS can cause very similar symptoms as well, any way to test these sensors?
Any suggestions would be greatly appreciated. Trying to get this figured out without just throwing new parts on it to see what fixes it.
1. Will a TBI motor run okay without an O2 sensor? I'm assuming that however many thousand miles ago it was that they replaced the exhaust, it must have run okay afterwards. Otherwise they would have put one back in I would assume.
2. Would the bad temp sensor at the thermostat housing cause the motor to run too lean once warmed up? Seems logical to me. Any way of testing this sensor? The temp gauge seems to work great, but I'm assuming that it is tied directly to the sensor between 1 and 3 spark plugs.
3. I've read that TPS can cause very similar symptoms as well, any way to test these sensors?
Any suggestions would be greatly appreciated. Trying to get this figured out without just throwing new parts on it to see what fixes it.
Congrats
