88 K5 Will not run - only 8.48 v at fuel pump! - Page 2

THEMCGUIRE · 11-10-2009, 03:41 PM

I connected the fuel pump directly to the battery and disconnected the filter. Fuel flows to the filter.

I disconnected the fuel line to the back of the throttle body and shot air through it Air flows - apparently no blockage.

I cannot find a fuel pressure regulator. Fuel line flows from tank directly to throttle body via the filter. Could the fuel pressure regulator be part of the sender unit (Sender unit is new also) I do not have any floors or fenders on the truck right now total rebuild pending so everything is exposed.

Another issue I had forgotten until now ----

This truck was towed by the police for being on the street too long -49 hours. They did not have the key so they disconneced the linkage from the trans. When I had it towed back home the driver reconnected it.

However, I can push this truck forward and back while in park. I do not know why and was putting this off until I got the body back together.

Like I said it will run with starting fluid but not stay running. I thought that if it will start with the starting fluid then it could not be the Park /Newtral safey switch. But could this have been messed up when it was towed?

Any ideas...

oakknight · 11-10-2009, 06:30 PM

the pressure regulater is built into the tbi unit

kauzenkaos · 11-17-2009, 01:34 PM

i dunno if you fixed this yet but you can pinch off the return line to see if its the regulator. only problem with that is the soft parts on the lines are steel braided. and when u jumpered battery voltage into the relay did you get battery voltage at the pump. and did you clean and tighten the bolt on the frame for pump ground? i only ask cauz bad ground or wires can cauz voltage drop resulting in low psi.

THEMCGUIRE · 11-17-2009, 11:27 PM

I have not worked on it for a few days. Some town inspector came around saying that since the truck was just a bare bones it made my place look like a junk yard. I have a tent as big as a garage but not wide and it is hard to work in it. So I am trying to figure out how to continue "inside" the tent.

I do get 12 v when I bypass the relay. I plan on running a new line from the pos side of the relay. I also want to check the voltage at the injectors. Could it just be a fuse?

I will check all this when I figure out how to work on it and report back.

Thanks to all for your advise.

ryoken · 11-18-2009, 04:34 AM

this is gonna be a bad wire or connection... check your grd wire too....

11-10-2009, 03:41 PM	Posted in reply to Thunder's post starting "If the pump wont run when you power the..." #11
THEMCGUIRE Registered User Join Date: Jan 2009 Location: Lyndhurst, NJ Posts: 9 i Trader: (0 )	88 K5 still will not start - Could it be a safety switch? I connected the fuel pump directly to the battery and disconnected the filter. Fuel flows to the filter. I disconnected the fuel line to the back of the throttle body and shot air through it Air flows - apparently no blockage. I cannot find a fuel pressure regulator. Fuel line flows from tank directly to throttle body via the filter. Could the fuel pressure regulator be part of the sender unit (Sender unit is new also) I do not have any floors or fenders on the truck right now total rebuild pending so everything is exposed. Another issue I had forgotten until now ---- This truck was towed by the police for being on the street too long -49 hours. They did not have the key so they disconneced the linkage from the trans. When I had it towed back home the driver reconnected it. However, I can push this truck forward and back while in park. I do not know why and was putting this off until I got the body back together. Like I said it will run with starting fluid but not stay running. I thought that if it will start with the starting fluid then it could not be the Park /Newtral safey switch. But could this have been messed up when it was towed? Any ideas...

11-17-2009, 01:34 PM	Posted in reply to oakknight's post starting "the pressure regulater is built into..." #13
kauzenkaos Just Blazin Join Date: Jul 2009 Location: fallon nv Posts: 88 i Trader: (0 )	i dunno if you fixed this yet but you can pinch off the return line to see if its the regulator. only problem with that is the soft parts on the lines are steel braided. and when u jumpered battery voltage into the relay did you get battery voltage at the pump. and did you clean and tighten the bolt on the frame for pump ground? i only ask cauz bad ground or wires can cauz voltage drop resulting in low psi. __________________ 90 k5, small block 400, doug thorley headers, 454 tbi, catrer 60 psi fuel pump, performer intake, trans-dapt tbi plate, comp cam, keith black hypereutectic pistons (hope the tops dont pop off), erson 1.6 roller rockers, 4l80e trans, transgo hd2 shift kit, becotrols trans controller, d44 nitro trac lock, 12 b auburn gear, 4.56's, 35" mtr's, ord 6 inch front springs, swaybar disconnects, greasable bushings, hd shackles, ord 64" rear springs, hd shackles, greasable bushings Last edited by kauzenkaos; 11-17-2009 at 01:41 PM. Reason: cant spell

11-18-2009, 04:34 AM	Posted in reply to THEMCGUIRE's post starting "I have not worked on it for a few days...." #15
ryoken Vertasaurus Join Date: Jun 2003 Location: Jersey Shore Posts: 9,330 i Trader: (6 )	this is gonna be a bad wire or connection... check your grd wire too.... __________________ 87 K5. 350 TBI. 700R4/NP205. 4" TC Ez-Rides, zero rates.. Dana 60 moved up 1", 5:13's, 35 spline stubs with Rockcrusher Flanges... .4" DIY4X flip out back with 6" x-tied shackles and 56's. 14bff, 5:13's, disced and welded. 38" TSL radials. My Build Thread Gallery 1 Gallery 2 Posted by boggerless i hope the discharge from 1000 prostitutes is the mayo on your next samich Liberals feel zombies are just misunderstood, a conservative has a plan...

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11-10-2009, 06:30 PM	Posted in reply to THEMCGUIRE's post "88 K5 still will not start - Could it..." #12
oakknight Kraawl Join Date: Oct 2004 Location: Wichita , Kansas Posts: 158 i Trader: (0 )	the pressure regulater is built into the tbi unit

11-17-2009, 11:27 PM	Posted in reply to kauzenkaos's post starting "i dunno if you fixed this yet but you..." #14
THEMCGUIRE Registered User Join Date: Jan 2009 Location: Lyndhurst, NJ Posts: 9 i Trader: (0 )	I have not worked on it for a few days. Some town inspector came around saying that since the truck was just a bare bones it made my place look like a junk yard. I have a tent as big as a garage but not wide and it is hard to work in it. So I am trying to figure out how to continue "inside" the tent. I do get 12 v when I bypass the relay. I plan on running a new line from the pos side of the relay. I also want to check the voltage at the injectors. Could it just be a fuse? I will check all this when I figure out how to work on it and report back. Thanks to all for your advise.

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