|
|
|
|
| Author |
|
|
Registered
Join Date: Jul 2005
Location: Reno, NV
Posts: 5,941
|
fuel pressure question
As many of you know I have a UTCIS digital WUR in my car. I'm finally getting around to tune it again and here is my immediate problem.
I am commanding a control pressure of 4.5 bar and the DWUR is reading 2.5 bars hence it's running rich. So my question is where to look ?? What would cause the high fuel pressure ? I'm open to any suggestions.. Here's a screen shot . OOPS won't accept a bmp file.. sorry I'll work on that!
__________________
"Todd" 98 Tahoe ,2007 Saturn Vue 86 930 black and stock, 80 930 blue tracdog 91 Spec Miata (yeah I race a chick car) "life"ll kill ya" Warren Zevon |
||
11-10-2009, 03:36 PM
|
|
|
Registered
Join Date: Mar 2009
Location: New Windsor NY
Posts: 297
|
My case
In my case. After I got my engine rebuilt we switched the two fuel lines. The one that goes the the 7th injector and that WUR. It was giving almost full fuel all the time, causing it to buck. So after we put the gauges on and saw the pressure in the fuel the mechanic figured it out and switched the lines. Been a happy camper since.
Rob PS he had to retime the car and adjust the air/fuel ratio.
__________________
1985 Euro Red Carrera Coupe."SOLD",1985 White Targa Carrera. "SOLD",1977 Yellow 930. "SOLD",1991 Black 964 C4. "SOLD",2002 Silver 996 C4 Cab "SOLD", 2001 Polar Silver 996 twin Turbo |
||
|
11-11-2009, 06:37 AM
|
|
|
Registered
Join Date: Jul 2005
Location: Reno, NV
Posts: 5,941
|
No such luck here. Everything is in the correct place. I'll get it home tomorrow and check all the pressures with a guage over the weekend.
T
__________________
"Todd" 98 Tahoe ,2007 Saturn Vue 86 930 black and stock, 80 930 blue tracdog 91 Spec Miata (yeah I race a chick car) "life"ll kill ya" Warren Zevon |
||
|
11-12-2009, 05:56 AM
|
|
|
Smart quod bastardus
|
If I read your message correctly, you request 4.5 bar but are getting 2.5bar to the DWUR. Could it be one of the fuel pump relays or a pump are gone and you are not getting full pressure to the system?
Just a thought. A lower control pressure would cause rich running. Not sure what the pressure output of only one pump would be having never measured it.
__________________
1979 930 Turbo....3.4L, 7.5to1 comp, SC cams, full bay intercooler, Rarlyl8 headers, Garret GTX turbo, 36mm ported intakes, Innovate Auxbox/LM-1, custom Manually Adjustable wastegate housing (0.8-1.1bar),--running 0.95 bar max ---"When you're racing it's life! Anything else either before or after, is just waiting" |
||
|
11-12-2009, 08:27 AM
|
|
|
Registered
Join Date: Jul 2005
Location: Reno, NV
Posts: 5,941
|
Fred, Just re-read what I wrote.. I think you may be right I think I have a LOW pressure problem. I'm going to check the relays in the morning.. Wish me luck!!!
__________________
"Todd" 98 Tahoe ,2007 Saturn Vue 86 930 black and stock, 80 930 blue tracdog 91 Spec Miata (yeah I race a chick car) "life"ll kill ya" Warren Zevon |
||
|
11-12-2009, 06:21 PM
|
|
|
Smart quod bastardus
|
you know what i have a recurring problem with the one fuel pump relay working itself loose in the car and twice now have been driving and the car cuts out on me. First time it happened at a restaurant after i had parked the car and it would not restart....second time happened while driving.
I do not know what could cause the relay to work itself loose from the socket, but it pisses me off...try looking there too.
__________________
1979 930 Turbo....3.4L, 7.5to1 comp, SC cams, full bay intercooler, Rarlyl8 headers, Garret GTX turbo, 36mm ported intakes, Innovate Auxbox/LM-1, custom Manually Adjustable wastegate housing (0.8-1.1bar),--running 0.95 bar max ---"When you're racing it's life! Anything else either before or after, is just waiting" |
||
|
11-13-2009, 08:42 AM
|
|
|
Registered
Join Date: Jul 2006
Location: S. Florida
Posts: 7,249
|
The pins on the round red or black relays and the yellow relay are split pins that get squeezed together after time.
Take a knife and push it into the split and spread them a little and they will make a snugger fit into the relay sockets. |
||
|
11-13-2009, 10:03 AM
|
|
|
Registered
Join Date: Jul 2005
Location: Reno, NV
Posts: 5,941
|
I went out and checked the pumps and relays, both were working. When I fired it up, according to the WUR I'm getting good pressure now. HOWEVER it's still running pig rich.. I must have either a vacuum or a boost leak.. tuned for 14.7 AFR idle but goes right to 10-12 at speed and I'm tuned all the way up on pressure...
__________________
"Todd" 98 Tahoe ,2007 Saturn Vue 86 930 black and stock, 80 930 blue tracdog 91 Spec Miata (yeah I race a chick car) "life"ll kill ya" Warren Zevon |
||
|
11-13-2009, 07:46 PM
|
|
Herman the German
