Confirm my suspcions (fuel pump issue) ---> November 01, 2006, 07:10:50 PM Seems that everyone is having fuel-related problems this week.Chalk up another one.I moved the high-pressure pump on my '84 CFI Tbird to a location above the rear axle to create space for a ler. It's temporary, I'll be ditching the CFI soon enough. I moved the stock long plastic line that used to go from the tank to the pump, to go from the pump's new location to the filter which is on the opposite side of the frame rail from it's original placement. The tank to high-pressure pump fuel line is now a 3/8" rubber hose with EFI clamps on it.That was no big deal. After I got it done, I drove it around the block and it ran perfect. Sweet deal. Except that it hasn't started back up since.Okay, so troubleshooting 101. Car turns over perfect, just doesn't start. Pour a small amount of gas down the CFI TB and it farts and burbles. So it's not getting fuel.Check my pump wiring. Seems good. High-pressure pump kicks on for about a second when the key is in Run position. However, low-pressure pump doesn't appear to be doing anything at all. With line disconnected, key turned to Run, no fuel squirts out, no pump sound is heard. I'm fairly certain there's gas in the tank, it was heavy and sloshing when it was on my chest. So my questions are:1. Does the fuel pump relay (in the trunk) control one or both pumps?2. The reset switch feels all loose and flimsy, doesn't appear to be a definitive "position" to the tab. Could this be a culprit? I can get another.3. If I chunk the current in-tank low pressure pump and put an external Holley carb-type electric pump before the Ford high-pressure pump, will the chassis be low enough to still pick up fuel at the bottom of the tank? I know that in all the SEFI Ford cars I've dealt with, the pump itself has the "sock" and makes up the bottom five or so inches of the chassis' pickup. I didn't look at this one to see if it's the same.Anyways, I was gonna find all this out tomorrow, but figured I'd pose the questions first to save me some elbow grease. heh hehThanks in advance-dv Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #1 – November 02, 2006, 12:28:29 AM Quote from: 46Tbird;1111611. Does the fuel pump relay (in the trunk) control one or both pumps?dvBoth.Quote from: 46Tbird;1111612. The reset switch feels all loose and flimsy, doesn't appear to be a definitive "position" to the tab. Could this be a culprit? I can get another.dvIf the inertia switch were the problem, neither pump would run. Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #2 – November 02, 2006, 10:04:59 AM Good. Well that eliminates a couple of things then.Gonna find out if I have 12V at the pump tonight. Anyone else have any suggestions? Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #3 – November 02, 2006, 10:17:08 AM Did you say you had the tank down? Perhaps you pulled the connector loose? Aside from checking for power there's really not much else to it. You say the HP pump primes, but does it run when you are cranking?As an aside...I'd be interested in the CFI TB when you take it off. Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #4 – November 02, 2006, 10:35:01 AM sorry to hijack but chuck ive got the cfi tb im willing to get rid of. how much were you looking to spend?? Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #5 – November 02, 2006, 11:49:02 AM Quote from: Chuck W;111235Did you say you had the tank down? Perhaps you pulled the connector loose? Aside from checking for power there's really not much else to it. You say the HP pump primes, but does it run when you are cranking?As an aside...I'd be interested in the CFI TB when you take it off.Yep, it runs while cranking.Chuck, you can have this thing. You've helped me out a bunch. Want the fuel pumps too? How about the intake itself?What about the question concerning the in-tank pump chassis? When I switch to carb, can I eliminate the in-tank pump and just use an external electric pump connected to the factory chassis? Meaning, does the pickup tube go all the way to the floor of the tank, or does the pump itself make up the bottom 5" of the fuel pickup?I guess I'll find out tonight. :D Just wanting to get my mind prepped for what's there. I may just say screw the CFI and put a carb on it this week. Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #6 – November 02, 2006, 12:10:12 PM I guess you need to just see if the LP pump is getting power. Perhaps it just came unplugged if you had the tank up and down recently. I've seen some of those connectors get pretty brittle and coome apart.It's been a little bit since I put the 255hp pump in mine, but IIRC the pump and sock are on the bottom of the pickup cage.You will probably want to get crafty an braze a new pick-up tube in place of the LP pump. Some folks have just pulled fuel through the LP pump (I think my first '83 was set-up like that), but if you are planning on decent power, I'd get that restriction out of the way.As far as the TB goes, I have no need for an intake, but might be interested in the pump (HP), the TB and the engine harness. Got a couple plans for something. Just let me know. Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #7 – November 02, 2006, 01:16:31 PM The harness is gonna cost ya. :DYep, I'll check voltage at the pump and take a look at the physical connection. But remember it drove around the block - once. So I dunno.Yeah I figured I'd just end up making a new pickup tube. No biggie at all. Probably just cut all the chassis away, leaving the lid, and put a 1/2" pickup in it. Might convert the top to AN if I have time and can find an appropriate 90* fitting.thanks chuck... Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #8 – November 04, 2006, 11:26:50 PM just put a fuel cell in it. Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #9 – November 08, 2006, 10:01:50 AM This thing is kickin my ass.hahahaaaaI've been busy with a new house the past week so I finally crawled under it last night. The in-tank pump was DEAD. I mean, touch the leads across the battery post and NOTHING dead.Alright, so I mounted a Holley "red" carb pump outside the tank and modified the in-tank fuel pickup to work with it. This pump works fine, but now it seems to be the OTHER factory Ford pump giving me trouble. Gas is coming out of it, but not nearly the pressure I think it should be. Just kinda dribbles out. However, if I disconnect a line (pump off), I get a short blast of relatively high-pressure fuel.If I get the pumps to run a few times (key on/key off) before cranking, the CFI will spit and sputter when I do crank, but won't really fire up. What fuel pressure should I be looking for at the throttle body?If I've got a dead/dying pump, I'm bailing on this CFI shiznit and going to something that makes sense... sheesh. Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #10 – November 08, 2006, 10:33:44 AM The fuel pressure should be 39psi at the thottle body. Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #11 – November 08, 2006, 10:57:05 AM Gracias.I'm gonna go out on a limb here and say there's NO way it's 39psi I'm getting.Maybe 10-15.Guess I'll see tonight.Thanks again Chuck. Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #12 – November 08, 2006, 11:55:27 AM a holley red, blue, or black pump is a low pressure pump. Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #13 – November 08, 2006, 02:06:38 PM Correct.But the OEM high-pressure inline pump ('83-85? CFI cars) is still in place. The factory put a tiny little low-pressure pump in the tank of these to get the fuel into the line, and the high-pressure pump pressurizes it for EFI. Quote Selected
Confirm my suspcions (fuel pump issue) ---> Reply #14 – November 08, 2006, 05:49:54 PM Quote from: 46Tbird;112329 What fuel pressure should I be looking for at the throttle body?39 PSIoops I didn't read far enough in the thread. Quote Selected
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