GMC Jimmy Fuel pressure Problem

Tiny
KVN4
  • MEMBER
  • 1995 GMC JIMMY
  • 255,886 MILES
95 GMC JIMMY 256885 miles 4.3 vtec had erratic idle for couple of days. Cleaned iac valve this am now have crank no start. Checked fuel pressure koeo 60psi then drops to zero after 2 sec. A/c delco fuel pump put in 8months ago was getting tps code also. No start
Monday, April 2nd, 2012 AT 1:54 PM

15 Replies

Tiny
DJCL
  • MECHANIC
  • 767 POSTS
Check voltage @ starter
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Monday, April 2nd, 2012 AT 2:09 PM
Tiny
KHLOW2008
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Title had been truncated. Can you please elaborate?

If you had sprayed carb ceaner into the throttle body, it would definitely make it hard to start, at least for a while.

The fuel pressure driopping to 0 after 2 seconds indicate the fuel pump is working but you have a leak in the system. It could be from the fuel delivery line and intank or the fuel pressure regulator is bad.
Try clamping the return hose and testing the pressure to see if it drops, if yes, you would need to check the fuel pump side. If pressure does not drop, replace the fuel pressure regulator.
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Monday, April 2nd, 2012 AT 2:09 PM
Tiny
KVN4
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  • 48 POSTS
Had tps code yesterday with eractic idle but car started no problem. Cleaned iac valve this am and now have no start even with starter fluid. Checked spider area inside intake and just wet no gas smell. Tried startind seems to want to start but doesnt catch.
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Monday, April 2nd, 2012 AT 2:36 PM
Tiny
KVN4
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  • 48 POSTS
Any pics of fuel return hose. Or instructions. Thanks k
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-1
Monday, April 2nd, 2012 AT 2:39 PM
Tiny
DJCL
  • MECHANIC
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Ee if the plugs are soked might be flooded
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Monday, April 2nd, 2012 AT 2:42 PM
Tiny
KHLOW2008
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Is your system CPI or TBI? For TBI the pressure dropping to 0 when ignition is turned off is correct.
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Monday, April 2nd, 2012 AT 3:14 PM
Tiny
KVN4
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Cpi pulled one plug and gunked up and wet. Shall get new ones tonight when wife gets home as stuck for now. Is best way to change them to go through wheel wells. Will do tomorrow and let you guys know. Thanks again k
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Monday, April 2nd, 2012 AT 3:50 PM
Tiny
WRENCHTECH
  • MECHANIC
  • 20,761 POSTS
You're symptoms are pointing to a leaking fuel injector assembly. The early Vortecs were notorious for that.
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Monday, April 2nd, 2012 AT 3:58 PM
Tiny
KVN4
  • MEMBER
  • 48 POSTS
Changed plugs (i hate doing the left side) started right up but back to my high idle. Have code for the tps, could that be my problem or something else causing code. Money very tight but if you think should replace ill go with your advice.
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Monday, April 2nd, 2012 AT 8:54 PM
Tiny
DJCL
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Yes a bad tps can cause a hi idle. Can you check the voltage on all 3 wires and let me know what thay are with key on
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Monday, April 2nd, 2012 AT 10:48 PM
Tiny
WRENCHTECH
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Although you may have an issue with the TPS circuit, it certainly isn't your fuel pressure leak and not likely the cause of the fouled plugs.
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Monday, April 2nd, 2012 AT 11:14 PM
Tiny
KVN4
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  • 48 POSTS
Changed tps and started right up seems ok for now but am taking for ride tomorrow. Let you know if fixed. Thanks guys k
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+1
Tuesday, April 3rd, 2012 AT 12:14 AM
Tiny
DJCL
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Let me know how it works out
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Tuesday, April 3rd, 2012 AT 12:51 AM
Tiny
KVN4
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Alls fine runs great again, thanks guys. I did notice onmy scanner when monitoring data the timing was -21deg is that ok
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Tuesday, April 3rd, 2012 AT 2:00 PM
Tiny
DJCL
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That's. Ok
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Tuesday, April 3rd, 2012 AT 2:27 PM

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