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If the car starts (you feel, that engine started), but stops just after you disabled starter (turned the key from "start" to "run" position), I suppose it is more electrical issue with ignition / engine ECU circuits than with fuel. Anyway, checking fuel control and differential pressure is a good idea. We don't know how long this car stand not used. Maybe many years.
 

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Often times an electrical issue causes fuel problems in modern engine management.
 

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Does anyone know if there is a pump in the fuel tank on the Turbo R?
In all series 3xxxx cars IMHO fuel pumps are under the car, not in tank. There should be two(!) fuel pumps and fuel pressure accumulator. If they are missing you should rebuild that system...
 

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In a 1990 Turbo, there should be only one fuel pump, of course not in the uel tank but as szdowk says under the rear of the car.
If you put key on ACC you should hear the bzzzzzzz
 

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Simple...plug the VIN into the Bentley Heritage site (parts section) to see what your car has....why guess?
 

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Looks like throttle position switch is a binary device with common positive voltage, sourced at "overvoltage relay" (this relay with fuse at its top) and two outputs. Outputs will not be shorted to the ground(!) but to this positive voltage(!).
Oh, I just checked twice, I was wrong! The wire headed to the overvoltage relay, but it is the ground! (black-pink wire)
 

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Discussion Starter · #48 · (Edited)
The car came to me with a dead fuel pump. Replaced it with the correct Bosch unit which only lasted 20 minutes before dying. Double checked the new pump and it was open electrically. Replaced it a second time but wanted to be certain that there wasn’t an in tank pump, which I have since learned the Turbo R doesn’t have.
The published spec is 6.3 bar as per the updated service info. I will test the pressure after lunch.
 

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Jamie,
I'm late to the discussion, not entirely certain about the 30,000 series cars and you have the likes of Jim Walters opining (before whom I am useless :) ) BUT... The symptom you describe, i.e. start but cutting out seconds after, is a very common problem with a bad Engine Run Sensor on the 20,000 and earlier cars. Just a thought.
 

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Discussion Starter · #51 ·
Thanks everyone for their input and ideas. I figured it out.
i hadn’t realized that the 30,000 series cars had a fuel pressure increase to about 90psi so I had been testing fuel pressure but at the incorrect spec. The fuel pressure would hit about 55psi, the engine would start and the pressure would drop to about 35psi and the engine would stall. I did a ‘deadhead‘ test on the pump and it delivered 145psi no problem. I then replaced the fuel pressure regulator with an inline gauge and used the leakdown test valve to ’regulate’ the system pressure to around 90psi. Car starts and runs fine, so I’ve ordered a fuel pressure regulator which will be here in the next week or so. I will publish what happens after I replace it.
Gauge Yellow Measuring instrument Font Gas
Gauge Yellow Measuring instrument Font Gas
 

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Discussion Starter · #54 ·
Update
Fuel pressure regulator arrived yesterday and I installed it with the exact same result !!! Cranking fuel pressure of about 55psi which is far to low. I installed the fuel pressure gauge between the pressure regulator and fuel distributor and partially closed the inline valve which raised the fuel pressure to 90psi and the car starts and runs immediately. What is odd is that after the car is running I can open the inline valve and the fuel pressure will stay at 90psi and the car runs fine. However, shut it off and the fuel pressure immediately drops to 55psi and holds there, even overnight. I seem to recall that previous K Jetronic version had a pressure regulator set up built into the fuel distributor. I assumed (perhaps incorrectly) that due to the fact that this system had an external pressure regulator that the internal one wouldn't be used.
It's a long weekend in Ontario and I'll get back to this next Tuesday.
 

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Pressure is within. 1 bar
Looks good. Should be around 0,4 exactly.

Can you hear fuel pump for about 0,5-1s when you turn the key from "off/lock" to "run" position? (without cranking, open rear doors or windows to be sure)
IMHO if the fuel pump circuit is good, fuel pressure can drop itself fast when: one or more injcectors stuck open (inc. starting one), fuel pressure accumulator is not working or there is other main fuel leakage somewhere (EHA is not leaking? Check with finger ;) bellow EHA, after build fuel pressure). Check also all fuel lines, if they are properly connected :?
 

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Discussion Starter · #60 ·
The issue is the the fuel pressure is too low. It runs about 3.5bar and it should be 6.3bar
 
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