98 GMC K2500 454 Build

[Mangonesailor]

As long as all the cylinders are above 100 and within ~10% of each other that's fine.

Get some carb cleaner or anything really to spray on those leaks and see if it causes the truck to stumble, if it does then that's probably the root of your problem.

Just remember to do this with the IAC or the TPS unplugged. If you don't then the computer will compensate via the IAC and the motor will never rev up when the carb cleaner gets sucked in.

Also, OP, I noticed there is RTV around the exhaust manifold gaskets... do you know if your motor has been taken apart before?

 

[volunteerff21]

Just remember to do this with the IAC or the TPS unplugged. If you don't then the computer will compensate via the IAC and the motor will never rev up when the carb cleaner gets sucked in.

Also, OP, I noticed there is RTV around the exhaust manifold gaskets... do you know if your motor has been taken apart before?

Judging by the RTV im guessing it has. Someone probably already did the intake gaskets once and didnt seal them right.

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[Mangonesailor]

Judging by the RTV im guessing it has. Someone probably already did the intake gaskets once and didnt seal them right.

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Head gaskets you mean? There's no real reason to use RTV on exhaust gaskets from the factory.

You haven't replaced the intake manifold gaskets yet? They're likely due. Since you have new injectors, be sure to compare the fuel wash between them all to see if one is not spraying as it should.

 

[volunteerff21]

Head gaskets you mean? There's no real reason to use RTV on exhaust gaskets from the factory.

You haven't replaced the intake manifold gaskets yet? They're likely due. Since you have new injectors, be sure to compare the fuel wash between them all to see if one is not spraying as it should.

Misread your original post.

There isnt any RTV on the exhaust gaskets???? At least I dont see any.

RTV is all where the front of the intake meets the block. Which is why im guessing someone attempted this and mucked it up.

Head gaskets you mean? There's no real reason to use RTV on exhaust gaskets from the factory.

You haven't replaced the intake manifold gaskets yet? They're likely due. Since you have new injectors, be sure to compare the fuel wash between them all to see if one is not spraying as it should.

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[Mangonesailor]

Misread your original post.

There isnt any RTV on the exhaust gaskets???? At least I dont see any.

RTV is all where the front of the intake meets the block. Which is why im guessing someone attempted this and mucked it up.



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My bad, I looked again at your pictures. What I thought was the exhaust manifold is your water pump.

 

[volunteerff21]

Carb cleaner didny reveal any vacuum leaks at the lower intake. However I doubt leaking gaskets are helping anything.

If I still have the truck when my tax refund comes I may try and fix it then. I just really dont want to do all that work and it still have issues. And the fun time of re-setting the timing on the Vortecs. But we shall see.

For now it sits in my front yard with a for sale sign.

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[JScott23]

Just saw the truck on craigslist, thats some crazy stuff man. I can't say i've ever heard of that issue before, good luck! Truck is too nice to part with.

 

[volunteerff21]

Just saw the truck on craigslist, thats some crazy stuff man. I can't say i've ever heard of that issue before, good luck! Truck is too nice to part with.

When its a $400 a month lawn ornament it gets easier to part with lol.

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[JScott23]

Yeah man i understand 100%. I just got rid of my 454 tonight. Simplify everything haha.

 

[volunteerff21]

Yeah man i understand 100%. I just got rid of my 454 tonight. Simplify everything haha.

Yeah I saw you were trying to sell it. Im still on the fence about mine. Lot of money and time invested, and I do still have payments on it.

But then again I would really like a nice reliable truck lol.

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