2001 Jeep Cherokee 4.7L build

[SilverXJ]

If the cam isn't already damaged. You said it turned over and had valve tick? You didn't run it?

[Drv2e30]

If the cam isn't already damaged. You said it turned over and had valve tick? You didn't run it?

I did turn it over twice for less than a minute each time.

[SilverXJ]

I can't guarantee it, but you should be ok to just get new lifters and do a cam break-in

[Drv2e30]

However I have a new problem, oil pressure is acting up. I was getting low pressure and put a mechanical gauge on the engine, got the same results as the electrical gauge. Drops down to about 10psi and then down to almost nothing. I went ahead and replaced the pump (checked the cam whiAndrew oil pan was off and it looked good) Pressure gets up to 40psi when the engine is cold, but once it warms up the pressure drops below 10psi.

[Drv2e30]

So I'm back! and I had to have my machine shop rebuild my engine for me. Oil pressure isn't an issue with the new high flow pump I'm running.

However I'm stuck with a misfire issue.....

I've checked for vacuum leaks (found none), cleaned the throttle body(improved the idle), checked compression (no issues), regapped the plugs a few times (no help), swapped coil rails (no change), and upgraded the battery cables thinking there was a ground issue (idle improved).

I'm running the recommended NGK ZFR6F11 at .044 gap and I get a misfire when I drive around town. However, if I reset the OBDII just before a long drive I don't get the misfire until I start driving around town. Should I go with a different plug or should I just regap the plugs to a smaller gap?

-Sean

[SilverXJ]

re sync your cam sensor.

[jeepxj3]

Why 0.044" plug gap? I had a miss until I gapped to 0.035".

[Drv2e30]

re sync your cam sensor.

I've done that a number of times, including using the toothpick method. Here is a link I used:
https://www.youtube.com/watch?v=3Avy1mOUsAM

I can do it again though.

Why 0.044" plug gap? I had a miss until I gapped to 0.035".

It was the stock recommended gap for the NGK plug and was recommended on the forum at that gap. I would be up for trying the smaller gap to see how it fairs.

[RenoF250]

Is it a consistent miss? I wonder if an injector is not failing when it gets warm. Have you driven it awhile and checked if any plug looks different?

[SilverXJ]

I've done that a number of times, including using the toothpick method. Here is a link I used:
https://www.youtube.com/watch?v=3Avy1mOUsAM

WOW. That video is complete shit and needs to be deleted. 1) When the timing marks are lined up the engine is not at TDC on the compression stroke, which it needs to be at. 2) using marks from a previous engine, even after transferring them after paint??? NO, 3) As with the timing chain marks the cam sensor is not indexed correctly.

Take it out, do it again.

See here: http://jeep.blackonyx.net/pdfs/jcss.pdf

In short:
1) find top dead center on the compression stroke on #1 cylinder: Remove all spark plugs, rotate engine until you feel compression out of the #1 cylinder. Continue to rotate until the piston is at TDC and the balanced lines up with the 0 timing mark on the chain cover.

2) Drop the cam sensor/oil pump drive: Align the holes in the body of the drive to the hole in the reluctor wheel. Hold with a tooth pick or other stiff firm fitting item. Point the window in the body toward the rear and drop the sensor in. If the sensor drive doesn't want to go in, remove it and rotate the oil pump until the sensor drive drops in with the opening toward the rear of the engine. Install hold down and tighten. Install sensor and plug and fire up.

[Drv2e30]

I've done that a number of times, including using the toothpick method. Here is a link I used:
https://www.youtube.com/watch?v=3Avy1mOUsAM

WOW. That video is complete shit and needs to be deleted. 1) When the timing marks are lined up the engine is not at TDC on the compression stroke, which it needs to be at. 2) using marks from a previous engine, even after transferring them after paint??? NO, 3) As with the timing chain marks the cam sensor is not indexed correctly.

Take it out, do it again.

See here: http://jeep.blackonyx.net/pdfs/jcss.pdf

In short:
1) find top dead center on the compression stroke on #1 cylinder: Remove all spark plugs, rotate engine until you feel compression out of the #1 cylinder. Continue to rotate until the piston is at TDC and the balanced lines up with the 0 timing mark on the chain cover.

2) Drop the cam sensor/oil pump drive: Align the holes in the body of the drive to the hole in the reluctor wheel. Hold with a tooth pick or other stiff firm fitting item. Point the window in the body toward the rear and drop the sensor in. If the sensor drive doesn't want to go in, remove it and rotate the oil pump until the sensor drive drops in with the opening toward the rear of the engine. Install hold down and tighten. Install sensor and plug and fire up.

lol SilverXJ you are exactly what is necessary to get this working! I will definitely try this.

[Drv2e30]

Would it even run if I was 180 degreees off?

I reset the cam sensor, hopefully this does the trick.

Should I regap to .035 if this doesn't work?

[Drv2e30]

So I got another 77 Miles before it threw a code. I'll pull it tonight.

Here are some pictures of the spark plugs when I reset the cam sensor.

photo 1.JPG

photo 2.JPG

I noticed a little bit of red speckling which I'm guessing is from bad gas.

-Sean

[Cheromaniac]

Plugs don't look bad at all, and the red speckling could be from additives in the gas.

[Drv2e30]

So just before I checked the codes, the CEL went out. So I'm going to run for a little while to see what happens. I need to pass emissions soon!

-Sean