1992 chevy c1500 350ci TBI , Terrible Hesitation HELP !!!!!!

Old 03-14-2009, 01:32 PM
  #1  
jakedog3
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Default 1992 chevy c1500 350ci TBI , Terrible Hesitation HELP !!!!!!

92 chevy c1500 350ci tbi motor, I have a wicked hesitation from a stop, it goes all out for 10 feet maybe, then dies and takes off again fine. It feels and sounds like throttle stop !! lol. any thoughts where to start? Would the throttle position sensor cause this? Map sensor is new, What else is there? Any input would be appreciated ! thanks !!!
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Old 03-14-2009, 04:11 PM
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Tod74
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START WITH A NEW FUEL FILTER. tHEN FIND OUT HOW MUCH FUEL PREASURE IT HAS.
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Old 03-14-2009, 05:16 PM
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kwkracing
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Its the coil wire , pull the coil wire and i bet its corroded on one end, clean the end of the coil, replace the wire and the cap. If the wire looks good on both ends, it not this probelm.
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Old 03-14-2009, 07:39 PM
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MEMRACING62
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check everything the other guys have listed and also look at pick up coil in dist. I replaced a lot of these. when they start to go engine will try to die when you start of & when coming to a stop
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Old 03-15-2009, 06:24 AM
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johnracer
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two things come to mind and are very common. Pickup coil in distributor and spring in fuel pressure regulator corroded & broken.

Try unhooking the timing connector and driving it. If the hesitation is gone, it's the pickup coil.....
Connector is located on rh side of firewall under t-shaped plastic cover, taped to big harness. Tan wire w/black stripe.
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Old 03-15-2009, 12:21 PM
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jakedog3
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Default UPDATE !!!!!!!

thanks for all the tips, still have the hesitation, i did change the fuel filter first thing, i tried disconnecting the wire and still there !!! somwhere else i read EGR Valve, it said disconnect and plug the lines and try it but it still did it to !!! then upon further digging i scanned the computer and it has a code and reads as follows............

EGR open command did not change MAP sensor signal. Normal EGR flow should cause slight decrease in manifold vacuum which would change MAP sensor signal.

Now i guess maybe i will replace the EGR??? also i see there is a EGR Vacuum Solenoid ??? maybe i should replace that to???? Any thoughts???

thanks !!!!!!
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Old 03-15-2009, 01:53 PM
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MEMRACING62
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does it also idle like crap? if so valve could be stuck open, some of the egr valves you can stick your fingers into back of valve and snap it open and closed and see if that helps . engine should want to die when you push it open at idle. remove and clean and make sure it seals shut
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Old 03-15-2009, 05:49 PM
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johnracer
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Does it actually have good vacuum to the map? I've seen the port in the throttle body that feeds the map become plugged or partially plugged and cause hesitation. The ones I've seen actually had vacuum, but was restricted enough that it cause a delayed response to the drop in manifold vacuum.......causing hesitation. Tee a vacuum gauge ino the map line and make sure it has vacuum and that it drops immediately at throttle movement.
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Old 03-16-2009, 09:21 PM
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radicalz
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Originally Posted by MEMRACING62
check everything the other guys have listed and also look at pick up coil in dist. I replaced a lot of these. when they start to go engine will try to die when you start of & when coming to a stop
MEMRACING62 is right check the pick up coil and the ignition moduel in the distributor....my 92 k1500 with 350 had to replace distributor 2 times because the pick up coil in the distributor was bad
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Old 03-17-2009, 12:32 AM
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Man does this bring back a bad memory, my ole lady drove my 95 suburban down to her folks house in Belzoni Ms, just a few weeks ago.
My surburban only had 244,000 on it so i have no idea why it messed up..lol
But it's wents craps on her down there and she had no other option but to take to the country boy shop down there. Sounded like it was doing about the same as yours, hestating and stuff so here's the low down.
It ended up being the fuel pressure regulator, but that was after they put $500 worth of other parts on there first, here's a short list:
fuel filter, fuel pump, new coil, new high tension lead, new module and stator and of course the whole regulator assembly not the 40 dollar kit.

They said they clamped off the return fuel line and it ran great so try that, just might be your regulator.

Goodluck, Cp
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