Wow Dakaz you could practically eat off that engine bay.

If only I could keep mine half that clean.

 

The only reason I haven't replaced the sensor by the cat is because I was told it has nothing to do with how the engine runs?

 

You were given BAD information. Change the downstream sensor. This is from the factory manual:

Downstream Sensor: The downstream oxygen sensor (1/2) is also used to determine the correct air-fuel ratio. As the oxygen content changes at the downstream sensor, the PCM calculates how much air-fuel ratio change is required. The PCM then looks at the upstream oxygen sensor voltage and changes fuel delivery until the upstream sensor voltage changes enough to correct the downstream sensor voltage (oxygen content). The downstream oxygen sensor also provides an input to determine catalytic convertor efficiency.

 

I have now replaced upstream and downstream sensors and the truck still does the same thing

 

Have you pulled out the air temp sensor and look at it? Its on the intake manifold cant miss it check your spare vacuum port make sure its plugged up.

Have you checked the distributor ignition pickup? Its under the rotor remove the plastic cover that's it.

Sometimes its as simple as the coolant temp sensor

Only other is the crank position sensor

 

The 2.5 engine has a flaw that's irritating but easily avoided and you listed it the take off from a dead stop to acceleration burp/hiccup the only way to avoid it is feather the clutch and gas it this gets you past the burp/hiccup that's why I'm always fastest off the gun green light.

You may have put the timing chain on wrong or a bad or misaligned distributor.

The 2.5L is a very simple engine

By the way I have talked to many 2.5 owners and everyone has the burp/hiccup problem

Check the intake manifold gasket you should never use a thick gasket only the thin ones why they develop air/vacuum leaks after a few months... use the OEM thin gaskets only

 

I'm about to check the IAT sensor the engine already has a new crank sensor... I'd like to think it would show up if the IAT was bad? Ill most likely just go get one real quick

 

You're going to go broke if you keep throwing parts at it. Buy/borrow/rent/steal a scanner so you can see what the sensors are doing instead of just replacing them randomly.

If you have an Android phone, you can buy a Bluetooth OBDII adapter for 25 bucks and the Torque app for another 5. That will actually give you a halfway decent scanner for the money.

 

Well I look at it this way those parts needed replacing anyway I say replace all sensors after 150K. But I do say keep the old ones as backups they come in handy at times.

Its still way cheaper than a shop at what $100 to $200 an hour

Sometimes a code never comes up

 

I guess I'm weird because I don't replace parts that are still functioning properly. And I'm not talking about checking codes. I'm talking about reading the data stream.