2.3L ('83-'97) rought idle for the first few seconds after starting, goes away after a minute or so.

[dgaskins216]

Review.
Idles weird/hunting idle until it warms up.
Air filter: Probably not bad enough to cause problems.
Have checked for intake leaks and can't find any.
Unplugging IAC causes a stall.

Can you test the IAT sensor?

I'll test as soon as I get back home heading to town to get new air filter now just to verify it doesn't fix anything, do you happen to know where the IAT is located?

 

[dgaskins216]

Review.
Idles weird/hunting idle until it warms up.
Air filter: Probably not bad enough to cause problems.
Have checked for intake leaks and can't find any.
Unplugging IAC causes a stall.

Can you test the IAT sensor?

should I just test it until it warms all the way up and make sure it hits the 190ish mark?

 

[SenorNoob]

Not a bad idea. I'd be more concerned with the cold number since that is when your having problems.

 

[dgaskins216]

Not a bad idea. I'd be more concerned with the cold number since that is when your having problems.

is that the sensor inside the air intake system closest to the throttle body?

 

[SenorNoob]

Yep. That'd be the one. It's the one called out by the P0113 code.

To get the resistance numbers you would want eh wiring unplugged and connect straight to the pins on the sensor. You could even take it out and put in some water to change the temperature to get readings at a few points along that scale.

Just make sure it's dry before you put it back in.

 

[dgaskins216]

Yep. That'd be the one. It's the one called out by the P0113 code.

To get the resistance numbers you would want eh wiring unplugged and connect straight to the pins on the sensor. You could even take it out and put in some water to change the temperature to get readings at a few points along that scale.

Just make sure it's dry before you put it back in.

sorry I know this is probably a stupid question but if I unplug it to test it how will there be power to test? or do you mean to unplug and test the harness wires going to the plug?

 

[SenorNoob]

You'd get the resistance across the 2 pins on the sensor with it unplugged.

You can check the voltage as well by connecting one lead of the meter to ground and the other to whichever wire is the signal return. This would be done with it plugged in.

Either test should have similar results.

 

[dgaskins216]

You'd get the resistance across the 2 pins on the sensor with it unplugged.

You can check the voltage as well by connecting one lead of the meter to ground and the other to whichever wire is the signal return. This would be done with it plugged in.

Either test should have similar results.

okay will do I'm on the way home with the air filter and I will test it and let you know thank you again

 

[dgaskins216]

okay will do I'm on the way home with the air filter and I will test it and let you know thank you again

so I put the new air filter in and I unplugged that idle air temperature/air charge temperature and it wouldn't read anything with it unplugged trying to test resistance I started the truck with the new air filter and that unplugged and it started up perfectly and then it was only reading 30 ohms at 50° where it said it should be somewhere around 58 ohms so I just plugged it back in and I'm going to buy a new sensor tomorrow and see if that doesn't fix it. hopefully it was just the air filter but I'll replace sensor anyways

 

[dgaskins216]

so I put the new air filter in and I unplugged that idle air temperature/air charge temperature and it wouldn't read anything with it unplugged trying to test resistance I started the truck with the new air filter and that unplugged and it started up perfectly and then it was only reading 30 ohms at 50° where it said it should be somewhere around 58 ohms so I just plugged it back in and I'm going to buy a new sensor tomorrow and see if that doesn't fix it. hopefully it was just the air filter but I'll replace sensor anyways

 

[dgaskins216]

although it does still seem to idle down or want to die out when hitting the gas pretty hard or shifting between reverse and drive

 

[SenorNoob]

IF you get no reading on that sensor, it could be causing your problems. I wish you luck with the new one.

 

[dgaskins216]

IF you get no reading on that sensor, it could be causing your problems. I wish you luck with the new one.

so I got the new sensor and that helped the starting issue but I checked fuel trim with my OBD reader and short-term fuel trim is jumping around from anywhere between negative 10 to positive 20 where my long-term fuel trim is negative 25 constantly still shifting rough I'm not sure where to go from here

 

[dgaskins216]

obd

 

[dgaskins216]

short-term fuel trim sensor 2 is sitting at 99 and doesn't fluctuate at all where short-term fuel trim sensor one and long-term fuel trim sensor both fluctuate