Fuel pump test terminal?

[Schrade]

Where is it?

I need to do pressure test with a jumped 12V source, since everything is dis-connected here...

http://www.zr1.net/forum/attachment.php?attachmentid=2880&stc=1&d=1381805561

'UNDERHOOD' - narrows it down a little... The first schematic already shows it near the drivers side somewhere. Anybody got a snappics here?

http://www.zr1.net/forum/attachment.php?attachmentid=2881&stc=1&d=1381806625

[Dynomite]

Fuel pump test connector TIPS (http://www.zr1.net/forum/showthread.php?p=115344)

[Schrade]

Thanks there Cliff...

Marc says 43 is good enough; FSM says 48 is minimum.

:confused:

[Dynomite]

Thanks there Cliff...

Marc says 43 is good enough; FSM says 48 is minimum.

:confused:

If I had my choice of going with Marc or FSM.......well......that is a No Brainer for me....Marc ALL the time :p

[Schrade]

Does this look like an OEM test connector?

http://www.zr1.net/forum/attachment.php?attachmentid=2882&stc=1&d=1381861120

[92whiteZ]

90% sure that is it. but there are others that know more than I.

[Schrade]

90% sure that is it. but there are others that know more than I.

Thanks!

Sure wish the 'others' would post up some more in the 'diags' thread tho'...

[Franke]

Schrade, on page 6e3-a-6 in FSM it says" 490red Fuel pump test connector located near battery. Must be the one you found. Goes to terminal 3 of pri fuel pump relay.

[Franke]

Concerning the fuel question. I want to make sure I understand what is being said here. The FSM indicates ign on - engine off pressure to be 48-55 PSI. Then ign on - engine idling fuel pressure to be 3-10 PSI less indicating regulator control is functioning. FSM then indicates approx. 43 PSI in idle. Is that what Marc is indicating? Static versus dynamic pressures.

[Schrade]

Concerning the fuel question. I want to make sure I understand what is being said here. The FSM indicates ign on - engine off pressure to be 48-55 PSI. Then ign on - engine idling fuel pressure to be 3-10 PSI less indicating regulator control is functioning. FSM then indicates approx. 43 PSI in idle. Is that what Marc is indicating? Static versus dynamic pressures.

Not sure there Franke; I had 44 static (NO leakdown) (which Marc says is sufficient (43) ). Kinda' bothers me, but he's the doc on this mill.

Dynamic idle with vacuum was 40 (I haven't seen his spec for THAT). I saw in FSM that spec drop dynamic is 3 - 10, so I'm good there. Need his feedback on it...

I'll test again when everything is dry-fit - yep all together dry, and dis-assemble AGAIN - familiarity, sequence, KNOWLEDGE ;)

Thanks again there...................

[Paul Workman]

Yes, that is the fuel pump test connector you have in your hand.

With the SWITCH OFF, jumping** from the POSITIVE battery terminal to that connector will run BOTH pumps as long as thus connected. Fuel pressure, depending on the pump(s) will rise to the level of the stronger pump - whichever it happens to be. (Mine run at about 53-54, STATIC if memory serves)

**Inserting a VOM (aka volt-ohm-meter by any other name) configured to read Amperes will verify both pumps are drawing proper current (4-5A each for a total of 8-10A)

With the engine idling, Marc says 43# is sufficient (mine is 45-46# at idle) which falls in line with the FSM. IF the pressure is lower, e.g, around 40# or less, it indicates a likely issue with delivery; either the primary pump is going south OR the FILTER needs to be replaced (mine was choked up at 38k miles) or something is impeding flow.

http://i185.photobucket.com/albums/x220/6PPC_bucket/tech%20files/7-5-09013.jpg (http://s185.photobucket.com/user/6PPC_bucket/media/tech%20files/7-5-09013.jpg.html)

Testing for proper current draw...

I've posted this before - maybe a couple times...

Configure your VOM to read 10A by moving the red lead to the "A" position on your meter. Then BEFORE making any connections, switch the meter to the DC "A" or "10A" setting.

http://i185.photobucket.com/albums/x220/6PPC_bucket/tech%20files/Fuelpumpcurrentcheck004.jpg (http://s185.photobucket.com/user/6PPC_bucket/media/tech%20files/Fuelpumpcurrentcheck004.jpg.html)

I use some alligator clip leads (Radio Shack, etc.) to connect the RED fuel pump test connector to the BLACK meter test lead, and another alligator clip lead from the POSITIVE terminal of the battery to the RED meter test lead.

http://i185.photobucket.com/albums/x220/6PPC_bucket/tech%20files/Fuelpumpcurrentcheck001.jpg (http://s185.photobucket.com/user/6PPC_bucket/media/tech%20files/Fuelpumpcurrentcheck001.jpg.html)

With each pump drawing the proper current (4-5A) the two should read 8-10A. If the test indicates only 4-5A, then one of the pumps is not drawing current for some reason. If it reads ZERO, (assuming the ignition switch is OFF) then neither pump is running. Check you fuses in either (half current/no current) case. (The reading below indicates normal current flow with both pumps working correctly).

http://i185.photobucket.com/albums/x220/6PPC_bucket/tech%20files/Fuelpumpcurrentcheck005.jpg (http://s185.photobucket.com/user/6PPC_bucket/media/tech%20files/Fuelpumpcurrentcheck005.jpg.html)

While testing current, that is a good time to observe STATIC fuel pressure. Somewhere between 53 and 55 is about right ± a pound or two...

For a dynamic test, you need to get a fuel pressure gauge extension (got mine at Harbor Freight) and tape the gauge to the windshield and go for a drive.

http://i185.photobucket.com/albums/x220/6PPC_bucket/tech%20files/FPtestLarge.jpg (http://s185.photobucket.com/user/6PPC_bucket/media/tech%20files/FPtestLarge.jpg.html)

Fuel pressure should be close to what you saw at idle, when driving at a steady speed of 45-50 (in my test case). At WOT, all the way to 7000 rpm, fuel pressure should be in the mid-low 50s (mine is 52-53 at WOT). If pressure drops off below say 48#? (check with Marc), then there is a delivery issue; either a pumping issue or some kind of impedance in the fuel lines, or perhaps even a regulator.

Let us know what you find.

P.

[Schrade]

Thanks Mr W; checked fuel pressure and changed the filter when I got it a year ago, and tried to get some jam out in the filter afterwards. Nothing... I swear I had 48 psi, but I can't find posted snappics.

Even tho' Marc H says 43 is good, I'm not satisfied here...