Mechanics

SPUTTERING

1998 Jeep Grand Cherokee • 118,000 miles

Been working on a 1998 Jeep Grand Cherokee Laredo with the 4.0 liter inline 6. Shortly after start-up it starts sputtering and surging and sometimes stalls. Had a code when I first looked at it (can't remember code off hand) that basically said it was loosing ignition signal. At this point I had replaced the crank sensor, the code has not returned however still having issue. Since then the plugs, wires, cap and rotor have been replaced and today the distributor was replace, this was due to a ticking noise that was coming and going and turned out that one of the bushings was worn and allowing the shaft to move back and forth. I also cleaned the IAC valve. Also after a few seconds of the issue it clears up and runs fine with plenty of power. Also customer told me today that the sputtering started at the same time the cruise control stopped working.
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JimsAuto
November 12, 2013.




IS the fuel pressure within spec?

Pressure 48 psi

Tiny
JimsAuto
Nov 13, 2013.
Does it seem like it is running rich when this happens? OR even running too lean? It almost sounds like there may be a temp sensor that is telling the wrong info to the computer causing it to run poorly for a short amount of time and then clear up.

When I checked live data the fuel trim has been within 2% of zero. However I has not acted up during anytime I have anything diagnostic hooked up
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Tiny
JimsAuto
Nov 13, 2013.
It finally started sputtering while I had it hooked to the scanner, the STFT went to -33.5%

Tiny
JimsAuto
Nov 13, 2013.

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