truck will not stay running after big line kit
 

Ok so I have a 97 12v with a 1/2" kit from the sender up to the IP. could not get it to run the other day and finally it fired up, would run for about 10 mins then die. Start back up run for about 5 mins and die.

Today I figured ok ill double check all the connections and see what happens. Went to start it, would barely fire over and finally started but I had to keep my foot on it. Now it wont idle. If it does it will for about 3 secs and shut off.

Now everything worked fine until I put this kit on.

The only thing I can think of that could be the problem is either:

I never used a bigger return line.
or
there is a float at the bottom of the strainer of my sender, I never took that out with the drawstraw. Could this be blocking flow?

Any input is appreciated

bump your fuel pressure ... its return line pressure isnt enough and its emptying the IP ... hence the not running .. pinch your new return line just a bit with a pair of plieres and see if when you let go if it dies .... if it does ... you have your problem :c:

Ok thanks! ill try that tomorrow. If it does die, should I use a bigger return line?

smaller .. or get a tork tec ajustable return line kit ... i think your pump is not keeping enough fuel in the pump to keep it running ... :tu:

Ok thanks ill try the pliers tommorrow. Now even though I went with 1/2 lines it wont keep enough fuel in the pump?

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Couldn't even get it to start today. Overnighted an adjustable ofv and see if thst helps.

Good idea ... :tu:

Ok so I put the ofv in, got it started runs awesome. Took it down tge street got it going good and parked it for about 5 mins. When I go to start it now I always have to give it a little pedal to get going, then it idled and ran perfect.

adjust the idle ... :humm:... again ...

It idles at 800. Its almost like it is hesitant to start and starts missing for 3 secs and clears out

Air intrusion .... Delete fuel heater from lift pump ... They leak ... Mine does it too ... Another thing to fix when I do my HG...:ouch:

Already deleted it it's almost like it's choppy for the first 10 seconds then smooth out and runs perfectly fine

Is the fuel shut off solenoid getting bound up maybe?
Or a bad connection @ shut off relay?
Possibles...
Hope it helps.
DD

Ill look into thay thanks

sounds like air intrusion as my truck does that same thing every morning ... what did you set your fuel pressure at ....


Also .. might think about a check valve at the return line so it dosent drain whats in the return line and that could be your studder also ... :humm:

does it smoke? -white-? for these few seconds

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OE mechanical lift pump? drain back?

I bought a ofv020 so i would imagine its set at 30. Where could i get a check valve?

Yes oem pump. Whay do you mean by drawback?

chances are the weight of the fuel in the 1/2'' line is partially draining back to the tank after you shut the truck off. the problem is compounded because your stock lift pump doesnt move nearly as much fuel as an electric ans the truck has to actually be running before its moving fuel. my truck used to start immediatly hen it had stock fuel lines. now even with the electric pump it is hesitant to start unless i let the electric pump purge for a few seconds before i crank. i bet because you cant purge the lines before you crank is why you are seeing a a hard start.

Anyway to solve that? Maybe a pump before the stock one?

Sorry it was supposed to read drain back ... Install one way check valve I return line and problem solved ....

no need for a electric pump unless you intend on doing some real power upgrades or something like that.... :nope:

Sounds good ill get a check valve today to put on the return line

do keep posted ... will be doing some work on my fuel system real soon ... so this info will come in handy :c:

Should I get a check valve for my feed line as well?

NO

Ok. So this is a stupid question oooook shoukd know tge answer too, but when i put that check valve on my return line the flow should go towards the tank or pump?

you want it to flow twards the tank ... it will open and flow under pressure and close when the engine is shut down .. :c:

Put the check valve in and it helped little if any. Im going to check connections one more time

Not a bad idea ....


is it still running ruff unpon fire up first thing after sitting over night. ??

Anytime after starting. 15 mins or 15 hours

figure out what you fuel pressure is.

Fuel pressure is good. Noticing now that it gets harder to start if I park on a hill or have less fuel in the tank

you didnt answer the question. what is fuel pressure?

what is it under a load
what is it idleing?

Fuel pressure is 21-24 at idle and when I shut the truck off it decreases slowly to about 4.

what is it under load? 4psi with the engine running or shut off?

under load you should be in the 30's 24 at idle is pretty good.

4 psi shut off. Couldn't tell under load because the gauge wasn't long enough. I just moved the throttle with my hand and it was like 36-37.

Im starting to think the fuel is draining back into the tank and not staying in the line.

I begining to wonder if your experience my be a cracked ot loose pick up tube ... .... if you have the time ... loosen bed .. on the right side and disconnect bed on the left side ... use a cherry picker to pick yp bed @ corner pocket ... pull sending unit and all and inspect for cracks in pick up tube ... :tu:.... had to do this to a gasser ... was a ton easier than droping tank or pullin bed all together :s:

The pickup tube is brand new

huh ... odd :humm::humm::humm:

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mabye take the check valve and place it between the return and the tank ... flow twards tank .. shouldnt open unless thiers about 5-10 psi of pressure behind it .. :c:

I put one on already.

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Im starting to think about putting a small lift pump in just to keep pressure in the line with the key on.

ok .. did you make the intake side of the LP bigger and the return also ?

I beleive the return side should stay factory sized .. to help with return pressure for this exact reason ... just a theory i was thinking about ... :humm:

Yes intake side is bigger. Return line is stock.