When my truck is idleing it has a skip to it. i just gave it a tune up yesterday. it will **** a dollar bill up the tail pipe. do you know if a bad valve would cause this problem or could it be something else?

A heavy presence of white smoke from the tail pipe is usually caused by a bad headgasket. If this gasket is bad, the vehicle may run rough as well as overheat.

check for clogged air filter and oxygen sensor if check eng light is on

Sounds like the converter is plugged. You may also have a timing issue. Start the car and hold a dollar bill by the tail pipe, if it gets sucked into the pipe you have a timing issue. If not you can disconnect the converter and see if it runs better, if it does then the converter is plugged.

The exhaust leak has to be corrected or you got
a vacuum leak & no fuel control or correct fuel trim

what it is is that the water jackets are blown not gettin in to the oil YET.depending on how hot u got it.ive never used but heard it has worked it comes in a tall can and seals and stops anti freeze from leakin in to the cyl 20 dollar can compared to 800 dollar bill its worth a shot good luck

you have warped your head or you cracked your head gasket

Do a compression check to confirm a blown or leaking head gasket. If the compressions are too far off that will be more indication of a possible head leak or crack in the block.

check the caylastic convertor may be stopped up . one way to check is crank up car let idle at the rear tail pipe hold a dollar bill in front of exhaust it should be flapping the dollar pretty good .

It sounds like you have mechanical problems with your engine instead of a "bad" sensor. You can pay for a scanner to be put on your vehicle, but the scanner takes into account, that the rings and valves, as well as the compression is all fine. The smell of sulfur you smell is oil going through your catalytic converter. A repair shop will first charge you for them to place a scanner on your vehicle yet that will not give them the answers they need so expect to pay for a compression test...both "dry" and "wet" (20 cc's of oil in each cylinder), to establish the condition of the rings and valves as well as an additional charge for a Cylinder Leakage Test. This is all done BEFORE they can tell you what's wrong. Possible engine replacement from what you describe here, yet get yourself a Haynes Manual, number # 50025, which is for your Jeep as well as a compression tester and vacuum gauge and you can diagnose most of the problem yourself.

The cheapest and quickest way to check the mechanical part of the engine is: while it's running, place a dollar bill under and against the tail-pipe. If the dollar bill flaps into the tailpipe at any time, then you've got Engine Mechanical Problems for this "test" shows that a valve or valves are either burnt, sticking or carboned up. Before doing anything involving test equipment, just take a paper bill and see if the bill goes up towards or inside of the exhaust pipe.

"00 Buck"

hey if you truely think it is your egr valve unhook it and if that is the problem then when it is unhooked it should run better and the codes should not come up. hey if you cahnged the 1 o2 sensor and not the other you probably made the code for the one u repalced come up again. i would recommened that you change both of the o2 sensors at the same time. try checking if your catalatic convert is plugged. how you do this is take a dollar bill and hold it at the end of your tail pipe while it is idleing and if the dollar bill stays still you have a plugged catalatic converter.