5.4 Check Engine Light ??
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Topic: 5.4 Check Engine Light ??
Posted By: FREEDGUY
Subject: 5.4 Check Engine Light ??
Date Posted: 05 Dec 2019 at 7:51pm
Just what does it take to set the light off ?? I recently had my plugs/boots changed and everything went well for about 2 weeks and I developed "ignition" noise in my portable DeWalt radio that I use because the dash radio doesn't work. Well,the "ignition" noise went away but I am dropping a cylinder when in O/D and try to moderately accelerate/maintain speed. The guy who helped me has a scan tool but says if the light isn't on, a code can't be read  . Any thoughts on what it's going to take to get the light on ?
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Replies:
Posted By: Dnoym N. S. Can.
Date Posted: 05 Dec 2019 at 8:00pm
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what year? B:-) Dnoym
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Posted By: john(MI)
Date Posted: 05 Dec 2019 at 8:02pm
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I think it sounds like one or part of one of the coil packs is going. My Tundra has coils on each plug. One didn't snap down all the way and I had the symptoms you are describing. Once I found it and corrected the problem I haven't had any problems since. ------------- D14, D17, 5020, 612H, CASE 446 |
Posted By: TDF
Date Posted: 05 Dec 2019 at 8:04pm
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My guess is coil. There are 8 of them. One per plug, that sit on top of the plug. As they go bad you'll get a miss under load, but wont throw a code. Eventually it will get bad enough to throw a code. Test them with an ohm meter to see if one is out of spec. TDF |
Posted By: FREEDGUY
Date Posted: 05 Dec 2019 at 8:12pm
Sorry, it's an '05
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Dnoym N. S. Can. wrote:Posted By: FREEDGUY
Date Posted: 05 Dec 2019 at 8:16pm
I wondered if they could be "ohmed" ? Do they need to be pulled to test or just the wire pulled for the lead? Thanks
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Posted By: steve(ill)
Date Posted: 05 Dec 2019 at 9:04pm
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I assume the motor did not "miss" prior to the plug change ? After the plug change you had a misfire, but no code is set. You get a code when the misfire is "bad enough" to set the code and light. There are some readers that will find potential codes, or real time data showing which coil / plug is the problem......... That being said, since it just started on the NEW coils and plugs, it could be a premature failure, or it could be that too much dielectric grease or antisieze was put around the spark plugs wire ( boot) and it is shorting the spark out to the cylinder head... You options are to pull them apart and look for problems, wait for a "bad enough" miss to set the permanent code, or get someone with a more elaborate code reader that can get real time data. ------------- Like them all, but love the "B"s. |
Posted By: steve(ill)
Date Posted: 05 Dec 2019 at 9:06pm
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I have had some success in the past with "playing" with the throttle to get codes to set.. You can stomp on the throttle for a few seconds and get a heavy miss, then back off, then do it again, then back off, etc... and sometimes that will get it to set a permanent code.
also, if your buddy did not try to get the code, go ahead and connect the meter and see if it gives a code... sometimes there is a "potential code" recorded prior to the light coming on. ------------- Like them all, but love the "B"s. |
Posted By: FREEDGUY
Date Posted: 05 Dec 2019 at 9:15pm
Only plugs and boots were replaced. NO GREASE OR ANTISIEZE was used. There was a miss prior to the plug/boot change, that's why I had it done and all was fine for several weeks, other than the noticeable "snapping" on the radio. Will probably wait for the light to come on. Thanks
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Posted By: HD6GTOM
Date Posted: 05 Dec 2019 at 9:30pm
| My son had the same pickup. He bought coil packs from the scrap yard. He kept 2 or 3 in the glove box at all times. It helps when he only lives a mile from the scrap yard. I forget how he checked them. Sure sounds like your problem. |
Posted By: Dnoym N. S. Can.
Date Posted: 05 Dec 2019 at 10:17pm
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A clogged fuel filter in a Ford F-150 truck will cause its engine to sputter and misfire. Ford reprogrammed the PCM a B:-) Dnoym |
Posted By: steve(ill)
Date Posted: 06 Dec 2019 at 1:18pm
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If you have replaced the coils and wires and it still does it,........ possibly the plugs are due ? ------------- Like them all, but love the "B"s. |
Posted By: TDF
Date Posted: 06 Dec 2019 at 6:11pm
You can check if it's getting power or signal without pulling but need to pull it to see what the resistance is through it to really tell if it is bad. They aren't hard to remove. TDF |
Posted By: mhankins
Date Posted: 06 Dec 2019 at 9:40pm
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If the sel light came on,the ecm will have a history code stored in it,even if the light is not on now. |
Posted By: fixer1958
Date Posted: 07 Dec 2019 at 5:53am
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If it hasn't flagged the CEL light it hasn't met the criteria yet to turn on the light. You need a scanner and not a code reader. With a scanner you can go into 'functional tests' and look in 'Mode 6'. It will keep a record of the number of miss fires and which cylinder. If all cylinders you probably have another problem. Also look at your fuel trims to see if it is running lean or not, weak fuel pump or flow, dirty or bad mass airflow etc.
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Posted By: bradley6874
Date Posted: 07 Dec 2019 at 7:45am
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Hook a trailer to it and take a 10 mile trip the light will come on the load will make the miss bad enough to set code ------------- You can wash the dirt off the body but you can’t wash the farmer out of the heart and soul |
Posted By: Stan IL&TN
Date Posted: 07 Dec 2019 at 8:45am
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If you have a noticeable popping on the radio then it is one of those new plug wires that is defective or is not seated completely and is arcing. I would pull each wire and reseat them. You can also spray the wires with a misting bottle of water in the dark while it is running and look for a visible arc. I guess a coil pack could be breaking down internally and also causing the issue then you would need it to throw that code to narrow it down. ------------- 1957 WD45 dad's first AC 1968 one-seventy 1956 F40 Ferguson |