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Unread 10-05-2013, 01:13 PM   #31
SpecialTwinky
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Quote:
Originally Posted by TJJP77 View Post
What plugs were in it before the Bosch plugs?

I still say pull the Bosch plugs and put some Champion or NGK plugs in it. Both were OEM specified at one point in time or another on the coil rail engines, so you know they work. Sometimes these coil-on-plug systems are sensitive to resistance/feedback in the plug circuit and that feedback shuts down the coil drivers in the PCM to protect it from damage. As an example, Hemi engines are notoriously sensitive to the brand of plugs that will work with them - Bosch platinum plugs will make a Hemi stall, yet Champion platinum plugs will not.
I had NGK plugs in and they did the same as the Bosch ones do

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Unread 10-05-2013, 01:48 PM   #32
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I had NGK plugs in and they did the same as the Bosch ones do
Were the NGK plugs just standard copper plugs or were they single platinum? Double platinum will work with the coil-on-plug setups but single will not. Copper is also fine and was what they started using as OEM in around 2004/2005-ish.

Are you sure the coil rail is seated properly on all the plugs and the wiring harness connector is fully seated and not damaged in any way? People have had similar symptoms when the rail isn't on all the way. Also be sure that the little tiny "coil springs" inside the boots are there and not corroded.
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Unread 10-05-2013, 02:01 PM   #33
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Double platinum will work with the coil-on-plug setups but single will not.
Single platinum will work, they just wont last as long as double...
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Unread 10-05-2013, 03:13 PM   #34
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Single platinum will work, they just wont last as long as double...
That's not always the case on coil-on-plug Chrysler products. There have been many threads on here over the years where single platinum plugs have caused misfires which are then cured by using standard copper plugs or double platinum plugs. Some plug brands are more prone to the problem than others.

Don't believe me? Oh well.

Do you have anything constructive to add other than just disagreeing with everyone? What do YOU think is the cause of his problem? Come on, I really want to know.
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Unread 10-05-2013, 04:25 PM   #35
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How can I fix the jeep running too rich? I have heard that fixing that can fix the issue.
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Unread 10-05-2013, 05:50 PM   #36
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How can I fix the jeep running too rich? I have heard that fixing that can fix the issue.
It may not actually be running rich - if the plugs aren't firing properly, you will have unburned fuel in the cylinders, giving the appearance of running rich. That's why I'm focusing on the plugs/coil so much.
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Unread 10-05-2013, 06:26 PM   #37
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It may not actually be running rich - if the plugs aren't firing properly, you will have unburned fuel in the cylinders, giving the appearance of running rich. That's why I'm focusing on the plugs/coil so much.
Oh. I am going to throw the NGK plugs back in and I found a couple bad boots on a vacuum hose. Hopefully this fixes it
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Unread 10-05-2013, 06:51 PM   #38
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Do you have anything constructive to add other than just disagreeing with everyone? What do YOU think is the cause of his problem? Come on, I really want to know.
You're the only one that I've disagreed with in this thread. As far as the OP's issue, I'll post when I have a recommendation...
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Unread 10-05-2013, 10:24 PM   #39
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I put the NGK plugs back in and found a bunch of cracks on several vacuum boots on different vacuum tubes. I took it for a test drive and I ran likes champ for about 40 minutes and then the cel began to flash for a few seconds and then it went off. That happened about 4 times in 15 minutes. I couldn't tell anything different when that happened. What could this mean? I'm going to take the battery off tomorrow and try again. I'm wondering if the computer was just trying to compensate for the vacuum being different. Any suggestions or comments?
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Unread 10-06-2013, 09:59 AM   #40
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Disconnect the battery to clear the codes; then drive it and see if they return.
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Unread 10-06-2013, 12:16 PM   #41
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You're the only one that I've disagreed with in this thread. As far as the OP's issue, I'll post when I have a recommendation...
Just as I suspected, you don't have anything constructive to add. Just your usual MO of being a contrarian to increase your post count.

OP - the CEL flashing is usually related to O2 sensors and is intended to get your attention to prevent catalyst overheating/damage. Have you checked to see what codes are present now?
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Unread 10-06-2013, 01:03 PM   #42
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Did that and now the light doesn't stay on and I just blinked. I got the code pulled and it was p0301 and p0300. There is one more vacuum hose boot that I am going to replace. Anything else that I should do?
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Unread 10-06-2013, 01:18 PM   #43
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Did that and now the light doesn't stay on and I just blinked. I got the code pulled and it was p0301 and p0300. There is one more vacuum hose boot that I am going to replace. Anything else that I should do?
Well, you're making progress. Cylinder #1 is still a problem. Maybe that plug is bad or you are not getting good contact with the coil. You said you replaced the coil rail - was it with another used one, a new aftermarket one or a new OEM one?

You may want to consider putting the old coil rail back on to rule it out. It may not have been bad in the first place.
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Unread 10-06-2013, 02:58 PM   #44
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Just as I suspected, you don't have anything constructive to add. Just your usual MO of being a contrarian to increase your post count.


Contrarian? Again, you're the only one that I've disagreed with in this thread...
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Unread 10-06-2013, 04:45 PM   #45
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...
Still nothing constructive I see. Keep padding away.
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