shaner517

96 4.0 4x4 174xxxmi auto.

So I reset the computer on my jeep after changing a temp sensor. And now im getting a huge power loss and multiple misfiring. Mainly when I try to accelerate quickly. But if I gradually accelerate it does eh alright gotta kinda play with it. So my question I know I need a new up stream o2 sensor waiting for it to come but would that cause these problems? Could this mean my fuel puMPs not working effectively? Any help much appreciated.

ZINGGG

I take it it didn't do that before the sensor change? .....

That's a good indicator that the sensor itself is faulty. And yes that can happen with a new, aftermarket sensor. Or did you mess with anything while changing out the sensor? Where did you get the temp sensor from? The one in the thermostat housing, correct? You didn't need to reset the computer doing that simple sensor change but it shouldn't have hurt anything

shaner517

I got the sensor from a local parts store and it was the temp sensor that controls the gauge on the dash. Also it has had these problems prior to the sensor just nowhere near as prevalent. The CEL came on so im going to get that looked at asap.

ZINGGG

Oh the temp sending gauge. That should have no affect at all on misfiring. You said you have done a tune up right? What brand spark plugs and did you ensure the gap was .035? And have you ran injector cleaner of any kind?

You definitely need to get the code pulled to better see what's going on here.

And the o2 sensor is still a great place to start. Have you put in that order yet? rockauto ships pretty quickly

shaner517

Thats what I thought. I have champion copper plugs at the .35 gap. I ran some gum out injector cleaner and sea foam through the tank. I got paid last night so ill be ordering that 02 sensor tonight. Ill get the code off of it when I get back to the house

ZINGGG

Good plan! Let us know what the code is so we have a better idea of how to help you out

tjwalker

Strategy for a check engine light / code is always the same. Post the EXACT numbers here (not just a description). Gotta use those codes as your bible for resolving the problem.

For a 96, you CAN get a two digit code using the "key-on, key-off" technique. While this two digit code can be helpful, the 96 is OBDII and fully capable of giving you the complete PXXXX code, which is far more helpful. You'll need a scan tool or a code reader or bring it to a parts store like Autozone where they will read the codes for free.

Here is the procedure for pulling the two digit code.
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OBDII models (1996 and “SOME” 1997 models) Put the key into the ignition, push down the odometer reset button, then turn the key to RUN with your finger on the button - and then release the button. The odometer will go through 1111111 through 999999, then display the car's serial number. It will then show the 2 digit error codes. The2 digit code is helpful, but it is not as specific as the full PXXXX code, which is only available using a code reader or scan tool, so generally I recommend using the code reader or scan tool. But if you have a CEL and don’t have access to a code reader or a scan tool, try the odometer technique to point you in the right direction until you can gain access to a code reader.

shaner517

Well I just got the sensor in the mail and installed. Immediately the CEL went off and it seems the misfire is gone but ill know for sure tomorrow l. But I still have a rough idle. Any ideas?