Author |
Message |
mikewire Samba Member
Joined: March 22, 2010 Posts: 802 Location: San Antonio, TX
|
Posted: Tue Oct 25, 2011 9:22 pm Post subject: |
|
|
^^ SGK is on to something there.
Yes I read your first post. My point is that, yes, you are getting pressure and by pinching the line your PSI changed, of course it would...your pump is making pressure. And in an open return FI system with functional parts, you should be getting at or above 35psi. I think your FPR is fine, probably both are good.
But, like SGK said you possibly have something going on upstream, possibly with the pump or filter, or a blockage in the line or at the tank outlet. Your pump isn't pumping the volume of fuel it needs to pump to get to operating PSI.
Since you bought the FI setup new, I would also suggest getting the pump part # and make sure you got the correct one you need.
Another thing to consider is your battery voltage, maybe the battery is simply low on V.
When I was troubleshooting my FI problems, I hooked the pump directly to the battery and tested it that way, letting it run continuously for a minute or so while I watched the PSI.
The funny thing is that even when you get your PSI problem resolved, there may be something else causing your FI to run for only a second. But I suppose that's the purpose of this sticky... I had a similar issue, and you can read my build thread to see details and how I fixed it, the link is in my signature.
One tip to check for sure, the white wire in the FI harness coming from the ECU needs to be on the -1 terminal on the coil for ground pulse to the injectors. Without it, the injectors will not fire, and the bus will only run on the fuel from the cold start valve (CSV), which is only enough for it to run for about 1 second. _________________ -Mike
@countdowngarage
@bigskyeuro
1972 VW Kombi 9 Passenger Deluxe w/ 2.0L F.I. VWAC swap
1965 VW Beetle Deluxe Bahama Blue |
|
Back to top |
|
|
Westfabulous Samba Member
Joined: January 07, 2007 Posts: 4207 Location: The tropic of Canada, dodging the giant flying moose of Surrey!
|
Posted: Tue Oct 25, 2011 9:49 pm Post subject: |
|
|
tootype2crazy wrote: |
Ok I pinched off the return line and operated the flap and the fuel pressure jumped up to 100! The gauge definitely is not at fault. Could it be that I have 2 bad pressure regulators on my hands? What are the odds of that? |
I wouldn't let the gauge off the hook yet. The results you got were expected, but the gauge could still be way out of calibration. Perhaps it should have been reading 120 PSI, instead of 100. I highly doubt that 2 FPRs are bad and giving the same reading. My gauge recently failed while on the rail, and I was incredulous at first to believe that it could have failed, but it did.
Look for that massive vacuum leak. Whenever I have introduced a massive leak I get about 1 second before it konks out. Look around the S boot and related to ensure all is good. Post pics as I suggested.
How did you set the air bypass screw on your throttle body after the install?
How is the timing set?
Points or pertronix? _________________ *****************
"I will gladly pay you Tuesday for a hamburger today." |
|
Back to top |
|
|
SGKent Samba Member
Joined: October 30, 2007 Posts: 41031 Location: Citrus Heights CA (Near Sacramento)
|
Posted: Wed Oct 26, 2011 2:48 pm Post subject: |
|
|
tootype2crazy wrote: |
SGKent wrote: |
you have a clogged fuel line, fuel filter, bad pump, or clogged outlet in the tank
When you pinch the line a tiny amount of fuel can push the pressure really high. When the return is open the pump can't supply enough fuel to keep the pressure up. Turn a garden hose on at a dribble and hold your thumb over the end. Eventually you will get enough pressure to get a high pressure spray but it will be small. Take your thumb off and it will fall back to a dribble. The way to test it is do a flow test into a bucket. If the filter hasn't been changed - and I am not going to read the full topic again to see because I have other things to do, change it first. Good luck. |
FYI the tank is freshly cleaned and coated and the filter is brand new. I will check the supply line for kinks and so on. If there are none the the process of elimination would implicate the pump I suppose. |
pump or the coating has left a tiny hole for fuel to run out of the tank and that is your restriction. If you hear the pump run or see the pressure increase a little when the flap is opened and you aren't getting pressure, it has to be something between the tank and fuel pressure regulator that is restricting fuel. _________________ “Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin |
|
Back to top |
|
|
tootype2crazy Samba Member
Joined: October 08, 2007 Posts: 1276 Location: St. Louis Missouri
|
Posted: Thu Oct 27, 2011 8:18 am Post subject: |
|
|
I drained the tank out of the hose that meets up to the fuel filter and the flow appeared to be full and copious. I'll stick a wire up in the supply side of the tank outlet and see if that helps. The other possibility is that the gauge is reading wrong and the pressure is fine and I have a massive vacuum leak that is causing this probelm. _________________ air-cooled or nothing for me
1978 Sunroof Deluxe Bus (daily driver)
1978 Transporter (mom's, making into a camper)
1970 Single Cab 2.1 turbo/EFI 6 Rib, 78 front beam, vanagon backing plates on rear (project)
2001 GTI VR6 (wife's) |
|
Back to top |
|
|
tootype2crazy Samba Member
Joined: October 08, 2007 Posts: 1276 Location: St. Louis Missouri
|
Posted: Thu Oct 27, 2011 3:02 pm Post subject: |
|
|
Ok the tank is definitely free flowing up to the filter. So I did a flow test by connecting a hose to the return side of the pressure regulator, allowing it to flow into a measuring device. After holding the AFM open for 30 seconds, the volume delivered was only about half of what it is supposed to be, or 1 cup instead of 2 cups. Since the filter is brand new, this would seem to indicate the pump is bad, right? BTW, grounds are cleaned up and the battery charger was connected while doing this test.
Another weird thing is that when I start it up it will fire right up and die after 1 second. But then if I try to start it again immediately after it dying, it won't start. It has to sit for 10 minutes or so before it will start up and die again. Any thoughts? _________________ air-cooled or nothing for me
1978 Sunroof Deluxe Bus (daily driver)
1978 Transporter (mom's, making into a camper)
1970 Single Cab 2.1 turbo/EFI 6 Rib, 78 front beam, vanagon backing plates on rear (project)
2001 GTI VR6 (wife's) |
|
Back to top |
|
|
mikewire Samba Member
Joined: March 22, 2010 Posts: 802 Location: San Antonio, TX
|
|
Back to top |
|
|
tootype2crazy Samba Member
Joined: October 08, 2007 Posts: 1276 Location: St. Louis Missouri
|
|
Back to top |
|
|
tootype2crazy Samba Member
Joined: October 08, 2007 Posts: 1276 Location: St. Louis Missouri
|
|
Back to top |
|
|
mikewire Samba Member
Joined: March 22, 2010 Posts: 802 Location: San Antonio, TX
|
|
Back to top |
|
|
RocketRod Samba Member
Joined: July 19, 2007 Posts: 641 Location: Colorado Springs, CO
|
Posted: Thu Oct 27, 2011 5:57 pm Post subject: |
|
|
As you tested before for volume with the afm flap opened, are you getting 12V at the pump? _________________ Why Yes it is a Magic bus!
Common Sense isn't so common. |
|
Back to top |
|
|
tootype2crazy Samba Member
Joined: October 08, 2007 Posts: 1276 Location: St. Louis Missouri
|
Posted: Thu Oct 27, 2011 6:16 pm Post subject: |
|
|
I've got some new information. I should have tested this in the beginning! I'm such an idiot. After reading mikewire's thread I realized that the injectors might not be opening and it may be running on only the cold start valve for that 1 second. So I pulled an injector and cranked it over, and nothing. No spray, no gas, nothing. So now I have to go about finding out why the injectors aren't opening. And yes, the wire is connected to the negative side of the coil. _________________ air-cooled or nothing for me
1978 Sunroof Deluxe Bus (daily driver)
1978 Transporter (mom's, making into a camper)
1970 Single Cab 2.1 turbo/EFI 6 Rib, 78 front beam, vanagon backing plates on rear (project)
2001 GTI VR6 (wife's) |
|
Back to top |
|
|
tootype2crazy Samba Member
Joined: October 08, 2007 Posts: 1276 Location: St. Louis Missouri
|
|
Back to top |
|
|
busdaddy Samba Member
Joined: February 12, 2004 Posts: 51057 Location: Surrey B.C. Canada, but thinking of Ukraine
|
Posted: Thu Oct 27, 2011 6:43 pm Post subject: |
|
|
tootype2crazy wrote: |
So now I have to go about finding out why the injectors aren't opening. And yes, the wire is connected to the negative side of the coil. |
But is the black wire laying along the left side of the engine connected? How about all the ground terminals (yes, even the ones under the plenum)?, and are all the terminals in the plugs connecting the DR and resistor block actually making contact or have they pushed back out of the plug during reconnecting?, and the wires going into those terminals? any corrosion, looseness or internal breaks beneath the insulation?
Seen the troubleshooting charts on page one? _________________ Rust NEVER sleeps and stock never goes out of style.
Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
Stop dead photo links! Post your photos to The Samba Gallery!
Слава Україні! |
|
Back to top |
|
|
tootype2crazy Samba Member
Joined: October 08, 2007 Posts: 1276 Location: St. Louis Missouri
|
Posted: Thu Oct 27, 2011 6:51 pm Post subject: |
|
|
I just did the trouble shooting for the injectors not opening from the AFC manual and the double relay is good, all the grounds check out, and the continuity of the wire going from terminal one of the ECU plug to the negative side of the coil is good. The trouble shooting manual said after this step to get a new ECU. No wonder the previous owner of this fuel injection sold it off! And yes the black wire is going to the positive side of the coil. _________________ air-cooled or nothing for me
1978 Sunroof Deluxe Bus (daily driver)
1978 Transporter (mom's, making into a camper)
1970 Single Cab 2.1 turbo/EFI 6 Rib, 78 front beam, vanagon backing plates on rear (project)
2001 GTI VR6 (wife's)
Last edited by tootype2crazy on Thu Oct 27, 2011 6:53 pm; edited 1 time in total |
|
Back to top |
|
|
busdaddy Samba Member
Joined: February 12, 2004 Posts: 51057 Location: Surrey B.C. Canada, but thinking of Ukraine
|
Posted: Thu Oct 27, 2011 6:53 pm Post subject: |
|
|
So you're definitely getting voltage at the injectors but no pulsed ground signals?
How's the terminals in the ECU plug look? _________________ Rust NEVER sleeps and stock never goes out of style.
Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
Stop dead photo links! Post your photos to The Samba Gallery!
Слава Україні! |
|
Back to top |
|
|
tootype2crazy Samba Member
Joined: October 08, 2007 Posts: 1276 Location: St. Louis Missouri
|
|
Back to top |
|
|
busdaddy Samba Member
Joined: February 12, 2004 Posts: 51057 Location: Surrey B.C. Canada, but thinking of Ukraine
|
Posted: Thu Oct 27, 2011 7:00 pm Post subject: |
|
|
Make sure they all stay in the plug when it's pushed on and the wires aren't broken internally. The troubleshooting manuals rock but don't take 35+ years of heat and vibration into account, maybe the ECU is bad but it's more likely the connection between the ECU and the rest of the system is hurting somewhere from old age and wear. A V/OHM meter is invaluable here. _________________ Rust NEVER sleeps and stock never goes out of style.
Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
Stop dead photo links! Post your photos to The Samba Gallery!
Слава Україні! |
|
Back to top |
|
|
tootype2crazy Samba Member
Joined: October 08, 2007 Posts: 1276 Location: St. Louis Missouri
|
Posted: Thu Oct 27, 2011 7:15 pm Post subject: |
|
|
When I stick a test light in the injector connector and crank it over the light just stays on constantly. That would indicate the computer isn't pulsing the signal right? _________________ air-cooled or nothing for me
1978 Sunroof Deluxe Bus (daily driver)
1978 Transporter (mom's, making into a camper)
1970 Single Cab 2.1 turbo/EFI 6 Rib, 78 front beam, vanagon backing plates on rear (project)
2001 GTI VR6 (wife's) |
|
Back to top |
|
|
mikewire Samba Member
Joined: March 22, 2010 Posts: 802 Location: San Antonio, TX
|
Posted: Thu Oct 27, 2011 7:26 pm Post subject: |
|
|
tootype2crazy wrote: |
When I stick a test light in the injector connector and crank it over the light just stays on constantly. That would indicate the computer isn't pulsing the signal right? |
It should pulse from what I understand - I used a DMM, not a test light and got varied readings.
This sounds very reminiscent of my problem...you read my build thread, the parts about where I found two connectors that I had mistakenly grounded, that grounded out the entire FI system, right? _________________ -Mike
@countdowngarage
@bigskyeuro
1972 VW Kombi 9 Passenger Deluxe w/ 2.0L F.I. VWAC swap
1965 VW Beetle Deluxe Bahama Blue |
|
Back to top |
|
|
tootype2crazy Samba Member
Joined: October 08, 2007 Posts: 1276 Location: St. Louis Missouri
|
Posted: Thu Oct 27, 2011 7:41 pm Post subject: |
|
|
Yes I read that part. My harness is all complete so it is easy to tell where all the wires go because they are all bent into shape and lay where they are supposed to go. I don't think I tested it right the first time as the positive wire to the electronic ignition was off. So I just retested it with the test light and that wire on and I got very strange findings. The light goes on with the key in the run position and then while cranking it does some really sporadic lighting up and then going out, not a consistent flicker at all. I am really lost here. I don't think the injectors are opening, but when I try to start it with the cold start valve disconnected, it sounds like it is trying to fire on a couple cylinders but can't quite start. Could that take me back to fuel pressure? Ugh. I do have Weber 40s in my basement that are already jetted to run. I am not sure this FI is worth the trouble. _________________ air-cooled or nothing for me
1978 Sunroof Deluxe Bus (daily driver)
1978 Transporter (mom's, making into a camper)
1970 Single Cab 2.1 turbo/EFI 6 Rib, 78 front beam, vanagon backing plates on rear (project)
2001 GTI VR6 (wife's) |
|
Back to top |
|
|
|