new engine does not want to run right

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K5Blazerboy87

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hey guys i just installed a new engine in my 87 k5 blazer i kept the tbi system so i had it sorta running but it wasnt running right now it doesnt wanna fire up at all when it does it will stumble spirt fuel smoke out of the tbi anyone knows what it could be thanks thinking about switching it to carb
 

PrairieDrifter

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Just don’t crank on it a bunch if you can’t get it to run. If it’s a brand new engine the cam needs to be broken in, if not cranking on it a bunch will hurt the cam and put a bunch of fuel in the oil
 

bucket

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First thing, check that your distributor is installed so that the rotor points to cylinder #1 at top dead center. Then check that your plug wires are routed correctly.

Is it a stock engine or what?

Switching to carb is often not the best answer.
 

K5Blazerboy87

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I installed a new distributor points to 1 it is at top dead center when i installed it
 

K5Blazerboy87

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Its a preformance build has about 300 horse preformance cam
 

bucket

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Double check the wire routing?

What's the specs on the cam? Is it still the stock PROM in the ECM?
 

K5Blazerboy87

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Ive got custom chip built for it has a new computer in it
 

K5Blazerboy87

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Wire routing is right
 

Dave Harding

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those tbi motors dont like change i had this truble once it kept jumping time hope u get her figured out man
 

Snoots

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Sure sounds like a timing issue tho.
 

Daveo91Burb

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You’re sure #1 is on compression stroke? Take that plug out and hold your thumb over the hole when bringing her up to TDC so you can feel compression.
 

K5Blazerboy87

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I did i made sure
 

bucket

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Swap the stock PROM back in just for poops and giggles?

I'm assuming it ran before the engine swap, right?
 

legopnuematic

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I second double checking TDC on compression and distributor rotor location. Even people who have been messing with engines for 40+ years have been known to stab one in 180 out.
 

73c20jim

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Once or maybe twice.
 

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