BlvdKreeper

Because I've replaced the tps,iac and map sensor and it's still the same.

VTJeep

ignition coil comes to mind.. bad ground maybe?

indeepwithajeep

You can have a bad enough vacuum leak to cause something like this. However I would remove your throttle body and clean your IAC and TPS and everything else in there. Use MAF cleaner (safe for sensors and plastic), you can find it in any auto store .


Found online for the IAC cleaning.
"1. Remove the Throttle body from the intake manifold.
2. Remove the IAC with a TORX 15 driver (2 bolts)
3. Gently wiggle out the IAC from the throttle body
4. Clean the IAC with Throttle Body Cleaner (not carburetor cleaner). Use cleaner, a rag, and a toothbrush. Be gentle; don’t twist or pull on the pintle as it is fragile and can be damaged easily
5. Also clean where the IAC seats in the throttle body with the same throttle body cleaner
6. While you have the Throttle Body off, give it a good cleaning also.
7. Reinstall IAC, the Throttle body, and check idle quality."


Found online for testing the TPS
"TPS TESTING

You may have one or more of these Physical Symptoms:

1) The engine loses power and is stalling.
2) The engine will idle, but may die as soon as you press the gas pedal. When driving, it seems as if all power is gone.
3) Sometimes it feels as if the transmission is failed or isn't shifting properly, if at all. If you quickly jump on the gas you might be able to get the transmission to shift, but it won’t shift properly by itself. Shifting manually, the transmission goes through all the gears.

NOTE: The throttle position sensor is also DIRECTLY involved with transmission shifting characteristics. The TPS function should be verified early in the troubleshooting process, when a transmission issue is suspected.

TPS TEST

You should have 5 volts going into the Throttle Position Sensor (TPS). It is best to use an analog meter (not digital) to see if the transition from idle to WOT is smooth with no dead spots. With your meter set for volts, put the black probe on a good ground like your negative battery terminal. With the key on, engine not running, test with the red probe of your meter (install a paper clip into the back of the plug of the TPS) to see which wire has the 5 volts. At idle, TPS output voltage should be greater than .26 volts but less than .95 volts. Move the throttle and look for smooth meter response up to the 4.49 at WOT. The other wire will be the ground and should show no voltage.

Perform the test procedure again and wiggle and/or tap on the TPS while you watch the meter. If you notice any flat spots or abrupt changes in the meter readings, replace the TPS.


The TPS is sensitive to heat, moisture, and vibration, leading to the failure of some units. The sensor is a sealed unit and cannot be repaired only replaced. A TPS may fail gradually leading to a number of symptoms which can include one or more of the following:

-Poor idle control: The TPS is used by the ECU to determine if the throttle is closed and the car should be using the Idle Air Control Valve exclusively for idle control. A fault TPS sensor can confuse the ECU causing the idle to be erratic or "hunting".

- High Idle Speed: The TPS may report faulty values causing the engine idle speed to be increased above normal. This is normally found in conjunction with a slow engine return to idle speed symptom.

-Slow engine return to idle: A failing TPS can report the minimum throttle position values incorrectly which can stop the engine entering idle mode when the throttle is closed. Normally when the throttle is closed the engine fuel injectors will be deactivated until a defined engine RPM speed is reached and the engine brought smoothly to idle speed. When failing a TPS will not report the throttle closed and fueling will continue causing the engine to return to idle very slowly.

-Engine Hesitation on Throttle Application: The TPS is also used by the ECU to determine if the driver has applied the throttle quicker than the Manifold Air Pressure sensor can read. The fueling is adjusted accordingly to cope with the sudden increase in air volume, however a faulty sensor can cause the ECU to ignore this data and the engine will "hesitate" when applying the throttle. In extreme cases with the engine at idle, a sudden application of full throttle can stall the engine.

- Engine Misfire: A faulty TPS can report values outside the acceptable range causing the ECU to incorrectly fuel the engine. This is noticeable as a slight misfire and can trigger the misfire detection software and/or Malfunction Indicator Lamp (MIL) light on the dashboard. Extreme cases can cause excessive misfires resulting in one or more cylinders being shut down to prevent engine and catalytic converter damage."



You might want to look into the stator in the distributor as well.
http://www.lunghd.com/Tech_Articles/...lse_Stator.htm


Here's a coupon.. You could buy something cheap like cable ties (that's about all they're good for) and get a multimeter free.



http://www.harborfreight.com/household/cable-ties/8-inch-black-cable-ties-pack-of-100-34635.html

93XJeeper

My jeeps oil pressure is all over the place, sometimes it works fine. So times it's really high and even off the scale. Then so times,,it's bouncing around. I just put a new oil pressure sender on it about a week ago. That helped a little. I also cleaned all the grounds down to bare metal, but it still does this. Should I try cleaning the grounds under the corner underneath dash?

HappyPappy

It's been said on here that a Dakota 4cyl is a direct fit

VTJeep

Refreshing grounds is always a good idea. But I doubt its the cause in this case. Maybe consider an aftermarket electric pressure gauge to help verify. Dummy gauge could be culprit.

93XJeeper

what do you mean by dummy gauge?

VTJeep

The stock dash cluster gauges are notorious for being unreliable.

NewKindOfClown

Especially oil pressure. It's more of a warning that something is wrong when it stays at one side or the other lol

93XJeeper

I always thought that only applied to the jeeps with the big gas Guage and no tach.

NewKindOfClown

Those are "dummy lights" when it's a simple on/off warning. He said dummy gauge, which is normally used for a temp gauge that says C/H or a pressure gauge that says L/H instead of using numbers.

The OEM oil pressure gauge is simply unreliable

93XJeeper

should I put anther in, or will I be fine as long as it doesn't constantly stay at a high or low oil pressure spot.

XJwonders

please don't help anymore if u aren't reliable

93XJeeper

wait what? lol

VTJeep

Just messing with each other.. Not directed at you! Wonders changed the last sentence of Clowns post..

lolz, referring to y'all by your CF handles is kinda funny..