danmiller369

my engine bogs down usually after about 20 seconds to a 1 min after start up when I'm driving away. It seems to happen at about 2nd gear and approximately 3k RPMs but not the precise.

upon acceleration the engine bogs down like i am giving it with no throttle.pushing the throttle down further does nothing. but after the short cut out it will pulse back up and get jerky and this happens a couple of times before going back to running like it should. and then i have no more issues.

now i talked to a mechanic and he said he cuts the cats on all his cars and never has this problem and he does not believe it to be the cat. (the cat was removed by previous owner)

now assuming its not the cat, what should i start with? the jeep has 190,000 mi.

i would also like to add that the idle under normal circumstances is fine, but once the bogging starts to happen and i stop the jeep the idle is a little crazy.

danmiller369

bump

Radi

What year and engine? I'd start by checking the TPS and IAC. Either can cause a bog and bad idle if they aren't operating correctly.

cruiser54

From Joe Peters and well stated. Sounds harsh but just makes sense:

"Let’s play a game.

You pretend that you are the only one that knows what year/engine/model, etc that you are asking about.

We will all pretend you never asked a question until you provide at least the bare minimum of information about your vehicle".

danmiller369

that would probably be helpful...its a 1996 4.0 HO

can i clean the tps with intake and carb cleaner? i already cleaned the throttle body very well. or should i just replace it?

karl4x4

No cleaning
Here from the factory manual:

The TPS can be tested with a digital voltmeter.
The center terminal of the TPS is the output terminal.
With the ignition key in the ON position, check the
TPS output voltage at the center terminal wire of the
connector. Check this at idle (throttle plate closed)
and at Wide Open Throttle (WOT). At idle, TPS output
voltage should be greater than .26 volts but less
than .95 volts. At wide open throttle, TPS output
voltage must be less than 4.49 volts. The output voltage
should increase gradually as the throttle plate is
slowly opened from idle to WOT.
end of manual quote

The most important part of the test. the voltage has to be gradually changing. No jumps in voltage. That would indicate a bad spot on the variable resistor inside.
You can also check this with TPS out of engine by using a Ohm meter. just see if the resistance change is gradual all the way true.

Radi

Don't clean the TPS with anything, it'll ruin it. See Karl's post on testing it. Watch the output carefully while slowly opening the throttle by hand looking for flat spots or drop outs.