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Symptoms of a bad injector or spark plug???

Old 07-15-2004, 12:44 PM
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Symptoms of a bad injector or spark plug???

I am having some significant hesitation issues when accellerating these days. I have always had a couple of flat spots when I accellerate in 3rd, 4th or 5th from 3,000 rpm on up, but it has gotten much worse recently. The truck still starts and drives the same, except for the jerky accelleration.

I have had the Check Engine light come on 4 times in as many weeks, and it has turned itself off 3 times. It came on again this morning on the way to work. I took it over to AutoZone during the last engine light episode, and the code the AutoZone guy said it was giving was "Left Bank Lean".

I only found a couple of threads that mentioned bad injectors, and they didn't seem to quite match my problem. I would greatly appreciate any input!

Thanks,

-Scott
Old 07-15-2004, 01:03 PM
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Clogged injector(s)?
Old 07-15-2004, 01:11 PM
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Try running a can of BG44K through your next tank of fuel. That will help the injectors. If you really want them clean, send them to RC Engineering to have them ultrasonically cleaned.

I've heard Sea Foam Injector Cleaner is good. I believe you poor 1/3 of the can through the PCV hose, 1/3 can in the oil, and 1/3 in the fuel tank. Most everyone has reported positive results.
Old 07-15-2004, 01:20 PM
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I used seafoam through the PCV - I did 5ish oz the first session, then about 3oz the second go around (using half the can). The rest went into my 1/4-full tank of gas. Major improvement, but my injectors were ok to begin with. Try a full can in your gas tank the next time you fill up... Couldn't hurt!

I know it says it works in the oil, but I'm sticking with the AMSOIL engine flush for that. Wouldn't help this guy's problem though anyway, his sounds more like a fuel/air/ignition delivery issue.
Old 07-15-2004, 01:28 PM
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Scott-

So you did or did not clean the MAFS?
Old 07-15-2004, 01:53 PM
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Have you checked the plug wires? I had a Mazda 626 that was stumbling somethin' fierce during acceleration. Turned out to be the spark plug wires. Just a thought...
Old 07-15-2004, 02:19 PM
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I got the lean CE light last week, they told me it was either the plug or wire so I replaced all the plugs and wires and everything seems good so I dunno.
Old 07-15-2004, 04:46 PM
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Originally Posted by <96 Runner>
Scott-

So you did or did not clean the MAFS?

Unfortunately, no, I did not ever get around to it. I am moving in two days, after which I will have a LOT more time to do maintenance. I am trying to save up the money to purchase a Fuel Kit from URD. If/when I am able to make that big purchase, it will be a while from now, so I still have to address the problem.

-S
Old 07-15-2004, 04:49 PM
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Originally Posted by roger
Have you checked the plug wires? I had a Mazda 626 that was stumbling somethin' fierce during acceleration. Turned out to be the spark plug wires. Just a thought...

No, but that is a good idea. I have a feeling this isn't the problem, since it doesn't happen on rough roads or while cornering. Since I don't know where the problem is, I will definitely check into this!

Thanks for the thought.

-Scott
Old 07-15-2004, 04:54 PM
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Thanks for the input so far

Thanks for the suggestions. I will look around for the BG-44K. That stuff is so d@mned expensive, it had better work miracles! I'm thinking that if I buy a BG-44k sticker, I should gain at least 5hp and 8lbs of torque!!! Haa!

-S
Old 07-15-2004, 06:31 PM
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Gadget,

Do you have an opinion on this?

-Scott
Old 07-15-2004, 10:38 PM
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Perhaps o2 sensor?? that could make it run lean
Old 07-16-2004, 02:58 AM
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Another thing to me is that the code explanation sounds very short. Left bank lean doesnt tell you much. When they pulled mine last week it read " Bank #1 lean/misfire , possible bad plug, wire, or coil pack". Maybe the guy at that autozone half assed it or something. You might let em pull it again and get the code then look it up yourself.
Old 07-16-2004, 03:27 AM
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Originally Posted by ElwayLite
Another thing to me is that the code explanation sounds very short. Left bank lean doesnt tell you much. When they pulled mine last week it read " Bank #1 lean/misfire , possible bad plug, wire, or coil pack". Maybe the guy at that autozone half assed it or something. You might let em pull it again and get the code then look it up yourself.

Thanks,

I do think the guy half-assed it. Shoot, he didn't even reset the code! I had to drive around for another several days before it reset itself. I'll find another AZ somewhere around where I'll be living next week and ask them to pull the complete code.

-S
Old 07-16-2004, 03:32 AM
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Update

I discovered a little more information that might help in the diagnosis.

I have found that if I very gently accellerate, I get virtually no hesitation. If I accellerate at 50% to WOT, the hesitation and jerkiness seems to be fairly porportional to the amount of throttle input. The more throttle, the worse the symptoms get.

I have not noticed any puffs of smoke, reduced fuel mileage, or longer starts. My truck has always taken a couple of moments to turn over, before and after installing the blower. I am beginning to wonder if the spark plugs are worn out and cannot handle the extra demands at high throttle input.

Thanks again for the ideas. I'll keep everyone posted on the outcome.

-Scott
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