YJ: Rough idle

[Kirby_YJ]

Hey guys i went through one mud hole on my way home the other day with no problems then parked it the jeep and a few hours later got in it and it started and was fine then while idling it acted like it lost power and was gonna die then would go back to normal right before it would die then would imminently lose power again and catch its self. It never did die so the next morning i drove it around the yard a few times and it didn't do it again but it does seem to be idling a little rough. any ideas? i dont wanna be on a trail somewhere and this happen again haha please help!

[SKIDOG74]

Hey guys i went through one mud hole on my way home the other day with no problems then parked it the jeep and a few hours later got in it and it started and was fine then while idling it acted like it lost power and was gonna die then would go back to normal right before it would die then would imminently lose power again and catch its self. It never did die so the next morning i drove it around the yard a few times and it didn't do it again but it does seem to be idling a little rough. any ideas? i dont wanna be on a trail somewhere and this happen again haha please help!

Additional Details
•Engine Size (L): 4.0 Liter
•Head Type: OHV
•VIN: S
•Fuel Type: Gas
•Number Of Cylinders: 6
•Number Of Valves: 12
•Type: Long Block


Brand Information

There are over 150 processes involved in remanufacturing each POWERTORQUE engine.

Featured procedures include:
•Engine blocks magnafluxed, bored, precision-honed & mains line-honed
•Camshaft bearings line-bored for accurate center-to-center clearance
•Engine blocks & cylinder heads precision surfaced
•Cylinder heads magnafluxed or dye checked & machined for three-angle valve seats
•Crankshafts stress-relieved, precision ground & micro-polished for optimum surface finish
•Camshafts precision ground or replaced with new to maintain OE specifications
•Each engine tested for compression, oil pressure, oil leaks, engine noise & general operating condition before shipment.
•Pistons & connecting rod assemblies balanced in sets to ensure proper performance
•Piston rings, wrist pins and wrist pin bushings replaced with new oil pump or oil pump kit supplied with each engine
•Premium Installation gasket set supplied with each engine
•Only brand name internal components assembled in each engine
•All Bearings are replaced with new
•Timing belts, chains and gears replaced with new
•All rubber products are OE quality (i.e. main seals, valve stem seals, cam seals)
•Industry best warranty
•Extensive coverage on Domestic, Japanese, European, Diesel, Marine, and Industrial Engines
•Manufacturing facilities are ISO 14000 & ISO 9001 certified



Manufacturer Information

Our mission at PowerTorque is to design, manufacture, and sell the highest quality engine and powertrain components in the automotive aftermarket. Customer satisfaction is our highest priority. PowerTorque products are used with confidence by Professionals and do-it-yourselfers alike.

[SKIDOG74]

How much for remanufactured engine? Help? Need opinion/expertise and/or pointed in right direction. I have a 95 jeep wrangler yj 4.0 l in-line 6cyl. I rebuilt upper and lower with pistons, main, rod bearings, honed cylinder walls. When i took off original timing chain. Marks were off one to two teeth. When put back together ran weak! I mean weak. 1it ran, but 1st through 5th were weak power. Could hardly make up a hill.

When i put back together, i aligned timing chain marks, distributor bug facing #1 spark plug while piston #1 was at tdc. Ran like shit. So i advanced a tooth or two or three and even retarded it one, two, three teeth. No start. Then i went 180 out, started but ran worse???

Replaces crank also. That only goes in one way right? I cant mess that up??? Please help me get my baby running????

[6spdYJ]

Haynes manual - Timing Chain Installation:
10. Be sure the crankshaft key is still pointing up. Note the locations of the locating dowel on the camshaft and the corresponding hole in the cam sprocket.
11. Pre-assemble the timing chain, crankshaft sprocket and camshaft sprocket with the timing marks aligned and facing out. Slip the assembly onto the engine in such a way that a line drawn through the timing marks will pass through the centers of the sprockets.
12. Install the camshaft sprocket bolt and tightened it to the torque listed in this chapter's specifications. Reinstall the thrust pin and spring.
13. To verify the correct installation of the timing chain, turn the crankshaft clockwise until the camshaft sprocket timing mark is at the 1 o'clock position. This positions the crankshaft sprocket timing mark where the adjacent tooth meshes with the chain at the 3 o'clock position. There must be 15 chain pins between the sprocket timing marks.

Hopefully the camshaft wasn't out of timing bad enough to impact valves and bend or break them or to damage pistons. Arbitrarily moving teeth on a timing chain can be a dangerous proposition. If it all lines up as the manual instructs, try checking for compression at the #1 cylinder with all sparkplugs removed. It should spin fairly easy with a ratchet handle and a socket on the damper bolt. Make sure you turn the crankshaft the right direction. Remember that the piston hits TDC twice during the power cycle - once at top of the power stroke and once at the top of the exhaust stroke. If the cam timing is correct, it will blow past your finger in the sparkplug hole as it approaches TDC. It should not blow past your finger during the exhaust stroke.

Hope it helps