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Discussion Starter · #1 ·
Ok so here's what i'm seein...

first off...91 K1500 TBI 350 Man Trans.

Second. Got good vacuum at idle with Map sensor vac line unplugged and gauge in it's place. Runs kinda choppy for a sec, then smooths out. after approx 20 seconds it "loads" up and dies.

Third. Map Sensor vac line plugged in. starts easily, idles good for a sec...then "loads" up and dies.

Replaced the following:

Intake Manifold Gaskets
Distributor
Map Sensor
TPS
IAC
O2
removed egr and capped the port.
capped all vac ports on TB, capped brake booster port at manifold. no change.
computer is throwing a code 33 Map vacuum high, pressure low.

only thing left to do is a compression check on the cylinders...maybe a valve is stuck open...

i dunno...someone else have a suggestion?
 

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HOT AIR BALLOON OWNER
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Have you tested the MAP via pulling vac on it? Get a MityVac tool, it is badass.

Fuel pressure? Leaking injector?

O2 sensor cycling properly?
 

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Discussion Starter · #3 ·
And yes, we used our mity vac to pull vac and it ran like a charm...pulled an even 15" on it...
 

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Discussion Starter · #5 ·
they are firing...but it's more of a mix of a faucet and shower head...than just straight shower...and the o2 is brand new.
 

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Discussion Starter · #6 ·
ok so apparently i'm an idiot....neither one of the injectors was firing properly...they were just like dripping out instead of spraying...

we changed them and voila! running truck!

lol.

Thanks guys!
 

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HOT AIR BALLOON OWNER
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:jester:
 
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