| Author | Message | ||
     Douglas McMillan (Mcmillan) Member Username: Mcmillan Post Number: 41 Registered: 06-2002 |
As some of you know I've been having some 'hard starting' issues on hot days with my 94 disco. Anyway I hooked up a pressure guage to the Schrader valve on the fuel rail and I am reading about 29psi. I compared this to my 95 disco which has had a fuel pump replacement a year or so ago and that was reading 32 psi and I have no issues with this vehicle. The recommended range is between 34 and 37 psi per the manuals. Now taking into account the analogue dial (which may have a certain tollerance of its own) is 29 PSI at the point where I should replace the fuel pump? That is about 2.0 Bars compared with the recommended 2.4 - 2.6 bars. PS I live in Colorado about 1 mile above sea level would that offset my readings? | ||
| Roland Kutasi (Disco1) Senior Member Username: Disco1 Post Number: 275 Registered: 10-2002 |
Hi Doug, I have an Autometer fuel pressure gauge fitted inside the cabin of my 95. On ignition it reads 60 PSI and drops to 50 PSI at idle. It would seem to me that you readings are very low. I don't think that the altitude would have a lot to do with your pressure drop if your fuel pump is doing it's job. | ||
| Paul T. Schram (Paulschram) Senior Member Username: Paulschram Post Number: 1690 Registered: 02-2002 |
My God, Roland, that is incredible fuel pressure. I have a gauge mounted on the fuel railto keep an eye on my pressure. It never exceeds 40 PSIG. I have heard accounts of Rover engines running on fuel pressure as low as 18 PSI. It was recounted as running, but not necessarily well. Peace, Paul | ||
| Shaun Power (Shaunp) Member Username: Shaunp Post Number: 41 Registered: 05-2003 |
At 60 psi I'd say your gauge or regulator is wrong. | ||
| Joey (Joey4420) Member Username: Joey4420 Post Number: 61 Registered: 04-2003 |
Could you have a bad fuel pressure regulator? Fuel pressure regulator The fuel pressure regulator is mounted in the fuel rail at the rear of the plenum chamber. The regulator is a mechanical device controlled by plenum chamber vacuum, it ensures that fuel rail pressure is maintained at a constant pressure difference of 2.5 bar above that of the manifold. When pressure exceeds the regulator setting excess fuel is returned to the fuel tank. | ||
| Douglas McMillan (Mcmillan) Member Username: Mcmillan Post Number: 45 Registered: 06-2002 |
Here is the latest from the tests I ran last night. On my 94 disco which has a problem the pressure is about 30 PSI with the ignition on. When I start the engine the pressure jumps to 36 PSI. This was with a hot engine. I then compared this to my 95 disco (which runs great) and it was 32 PSI constant with the ignition and again when I started it. Any thoughts from anyone? | ||
| Isidro J. Blanco (Chilin_12) New Member Username: Chilin_12 Post Number: 2 Registered: 06-2003 |
Purchased a '94 Disco with 94K. Idling problems with a lot of hesitation; and after changing the batery and the thermostat the Disco won't start. Checked pulse in the injectors (OK); fuel going to the injectors ( plenty ); spark plugs makes good spark; battery fully charged; distributor cap (OK.......engine crank but not firing??? what else do I have to check or do? I need you experts to help me out. NOTE: I know the gas tank has a leak and maybe some water probably gets inside the tank when I washed the engine. | ||
| Douglas McMillan (Mcmillan) Member Username: Mcmillan Post Number: 48 Registered: 06-2002 |
Chillin 12. Try switching the fan, radio, etc off and switch the ignition to the II position. Do you hear the fuel pump kick in? If not it may be toast. If you hear nothing get a fuel pressure guage and measure the pressure on the fuel rail on the RH side of the engine on the Shrader valve. You should have about 36 -38 PSI. 2.4 - 2.6 BAr. PS check out the fuel filter also. |
