1994 GMC Sonoma Fuel spider injector

1994 GMC SONOMA
113,000 MILES • 6 CYL • 2WD • AUTOMATIC
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TH4545
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What would cause the spider injector to keep going bad.I have had the truck for a year and already replace it twice and now 3months since the last one I thing it's gone bad again?
4.3 V-6 wvin number cpi
Nov 10, 2008 at 7:42 PM
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MASTERTECHTIM
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what is going wrong with them? leaking? hard start? usually when they are replaced they last a long time. i know these engines are very finicky about fuel pressure and volume and they have tons of problems with the rubber pulsator in the fuel tank. the pulsator connects the pump to the sender and ruptures causing lower fuel volume creating all sorts of driveability problems
Nov 10, 2008 at 7:48 PM
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TH4545
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The first two would make the truck stumbly around 1800 to 2200 rpm's.Finaly not running at all.This time it starts fine and with in 15 sec it stalls,starts right back up and wont have any other problem until i turn it off.Now it's doing the same as the first two and now very hard to start.Drive around with fuel preesure gauge and it does not drop below 60 psi when problems happen.

Also new fuel pump and filter about 1 month ago
Nov 10, 2008 at 8:09 PM
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MASTERTECHTIM
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did you replace the pulsator? its the piece the fuel pump slides into? the problem your describing does not sound like a injector problem. to check for proper fuel volume you need to install a amp meter in series with the battery positive terminal and the fuel pump test lead(the test lead is usually a gray wire or red wire by itself with a female connector at the end)
Nov 10, 2008 at 8:53 PM
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TH4545
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Had a fuel preusseure gauge on it holding the bleeder valve on the gauge pressure drops to 30psi and the truck stays running.Driving around the pressure stays around 58 psi
Nov 10, 2008 at 9:04 PM
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MASTERTECHTIM
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that is also a good test for fuel volume so that is ok. next step would be to watch data on a scan tool. monitor coolant temp, o2 sensor voltage to make sure you dont have a shorted o2 sensor. does the check engine light come on? did you check it for codes? you can jump terminal a and b on the diagnostic connector under drivers side of dash and it will flash the codes through the check engine light.
Nov 10, 2008 at 9:09 PM
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TH4545
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It has been on a scaner and has no codes.
Nov 10, 2008 at 9:30 PM
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MASTERTECHTIM
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when its hard to start, try spraying a shot of starting fluid into it and see if it starts right up. it needs spark fuel pressure and injector pulse to run, we need to find out what we are missing or losing. if you have a spark checker like a st125 that measures coil output voltage or another kind of spark checker but not the flashing light kind because that does not check voltage, we should have about 25000 volts. i have seen weak coils cause this same symptom.
Nov 11, 2008 at 5:03 AM
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TH4545
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i'LL check the voltage But all was new,I replaced it all when the first spider injector went bad.new plugs,wires,cap,rotor,dis,and coil.I was replacing everything i could thing of.It's just doing the same thing as the first two times the spider went bad.
Nov 11, 2008 at 8:11 AM
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TH4545
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Replaced spider unit and all is fine.Just hope this one will last
Nov 11, 2008 at 3:42 PM
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MASTERTECHTIM
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thats odd that they keep failing, i have never run into that before. good luck
Nov 11, 2008 at 5:08 PM