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Engine Idle Trouble

CoffeyLover

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CoffeyLover Enthusiast

CoffeyLover

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So last night I was driving my truck around in the rain just having some fun. Unfortunately, I happened to hit a huge puddle, sending water all over my CAI. Needless to say, the engine died. I got it started and drove home.

 

 

The truck will run and idle, so I know its not hydrolocked. But the idle is extremely bad, and the truck is throwing P0300. (One or more cylinders misfiring). Along with P0102 and P0103 (MAF sensor errors)

 

Does anyone have any ideas? I have cleaned the MAF sensor, although it does not change the engines attitude whether it is plugged in or not, could it be bad? I have used the Seafoam Spray in the intake, and it cleaned the carbon out, but did not fix my problem.

 

???

 

 

Thanks guys!

txab Senior Enthusiast

txab

Posted
Posted

Your MAF may be bad after getting soaked.

 

If engine is running, then there is no need to "get any water out" by pulling plugs

 

You access the plugs by pulling the plug wire off and there it is. A plug is a plug whether there is one coil or eight.

 

P0300 is a misfire code. Not a "not firing code"

CoffeyLover Enthusiast

CoffeyLover

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Your MAF may be bad after getting soaked.

 

If engine is running, then there is no need to "get any water out" by pulling plugs

 

You access the plugs by pulling the plug wire off and there it is. A plug is a plug whether there is one coil or eight.

 

P0300 is a misfire code. Not a "not firing code"

 

Okay, thanks for the info. What do you suggest I do?

CoffeyLover Enthusiast

CoffeyLover

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Here's what I'd do:

 

1. Seafoam it (break boot line and some in the tank)

2. Change the oil

3. Change or clean your CA filter

 

Alright, now I just have to figure out how to get to the parts store (Breakin' out the old bike!) But isnt there some special way to seafoam the vortecs?

CoffeyLover Enthusiast

CoffeyLover

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Also, I cleaned the MAF and put it back together. The engine runs, but the idle is way off and it is definitely misfiring. White smoke is billowing from the exhaust as well as an abnormal amount of liquid. The engine runs the same whether or not the MAF is plugged in.

 

Is this the MAF? Or is it possible that the plugs and wires need to be messed with?

 

Thanks,

gnet158 Senior Enthusiast

gnet158

Posted
Posted

Pull off your break boost hose and let it suck up the seafoam. You'll probably need someone giving it gas if your truck is running that ruff at idle. Let it suck up the whole can, let it sit for 30 minutes. Add a can to the fuel tank too. Start her up and watch out, it'll smoke like a MF. Drive her around until she stops smoking. If you don't know where the break booster line is then search on youtube, there's plenty of video's.

 

Hopefully that will help the idle, it may take a 100 miles or so until everything clears up. If it dose then make sure to change your oil once everything settles down. If not then check the plugs and wires. Good luck!

CoffeyLover Enthusiast

CoffeyLover

Posted
  • Author
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Pull off your break boost hose and let it suck up the seafoam. You'll probably need someone giving it gas if your truck is running that ruff at idle. Let it suck up the whole can, let it sit for 30 minutes. Add a can to the fuel tank too. Start her up and watch out, it'll smoke like a MF. Drive her around until she stops smoking. If you don't know where the break booster line is then search on youtube, there's plenty of video's.

 

Hopefully that will help the idle, it may take a 100 miles or so until everything clears up. If it dose then make sure to change your oil once everything settles down. If not then check the plugs and wires. Good luck!

 

So are you saying that the MAF isn't the problem? And the brake booster line doesn't reach all 8 cylinders does it?

CoffeyLover Enthusiast

CoffeyLover

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Alright, so I used the Seafoam spray, however to no avail. It did seem to clean the carbon out though! I heard all kinds of noise as the carbon pieces bounced off my exhaust.

 

Is there any hope in changing the MAF sensor? Like I said, the engine runs the exact same when it is plugged in and when it isn't.

 

Any thoughts guys? This is my DD and I really need my baby back!

tylerjenkins92@aol.com Senior Enthusiast

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Posted
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If I unplug my maf while it's idling it will stumble and blow black smoke for a second until it relearns I guess. If I unplug it while it's off and try to start it, it won't stay running unless I rev it a for a few seconds. But you should definitely tell a difference when you unplug the maf I would think.

CoffeyLover Enthusiast

CoffeyLover

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Well im going to install a new MAF sensor tomorrow. If that doesnt work, then its new spark plugs and wires. I don't really know where to go from there...

CoffeyLover Enthusiast

CoffeyLover

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Make sure to reset the computer also, when you install the new maf.

 

By just disconnecting the negative side of the battery? Or do you mean clearing the DTCs?

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