cuts out going down the road

1989 CHEVROLET CELEBRITY
145,000 MILES
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ZENACA
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Going down the road or sitting in the garage holding the throttle at about 1400 rpm or so,( rpms dont mater) the engine cuts out (skips)

The analyzer shows codes 22 &34 , TPS & MAP replaced both and still does it.And still shows 22 &34.After clearing codes and running again.
Checked vacume lines found a couple spots that were rubbed thin but not thru put some tape on the spots to see if it were a possible leak no change.

I cant find a shrader valve to chack the fuel press.so how do i go about doing that?

Pulling my hair out at this point and the wife is pissed i havnt fixed her car yet!
Apr 29, 2012 at 5:33 PM
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DJCL
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With the key on check the voltage on all 3 wires @ the tps and map sensor let me know what thay are. Is this the 4 cyl or v6 ?
Apr 29, 2012 at 5:49 PM
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ZENACA
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2.5 4cyl
Apr 29, 2012 at 7:51 PM
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DJCL
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Check the voltage on the 3 wires
Apr 29, 2012 at 8:10 PM
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ZENACA
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With the key on engine not running reading from each pin ,meter grounded to alternator housing
TPS
blue & black wires read .01 volt set on 20volt on meter
grey wire read .00

MAP
A &B read .01 volt
C read.00
Apr 29, 2012 at 8:11 PM
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DJCL
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Your missing the 5 volt refference signal on the to sensors. That gray wire must have 5 volts out of the pcm to the sensor
Apr 29, 2012 at 8:18 PM
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ZENACA
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What are the chances it is both wires to the sensors as opposed to being the pcm bad?
Apr 29, 2012 at 8:26 PM
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DJCL
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Thay share the same 5 volts if its missing @ the computer check all your powers and grounds
Apr 29, 2012 at 9:29 PM
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ZENACA
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I have another one of those cars i swapped computers, same problem .

So i tried moving the wire harness where it comes out of the fire wall while it was running and it smoothed out ,so i guess i just have to figure out which wire and where it is bad.
And there is SOOO much room to work in there this is going to be fun.

Thank You for all the help !!!!
Apr 29, 2012 at 11:27 PM
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DJCL
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Your welcome let me know if you need more help
Apr 30, 2012 at 12:06 AM