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Good night I have a 91 bentley turbo the engine has problems to start in when it's cold
I put ground to the cold start valve and start rigth away
I know there it's a switch for that but also I like to know if there is a relay
I guess you opened a second question. I will look for the diagram.
Or better the complete circuit can you help me
Are you still here
I am. Finding the Diagram. So the cold start injector is run completely by the module. Which means we are looking at a temperature sensor fault.
K the injector has power once the ignition is on
Correct. The control module supplies a duty cycle ground based off of engine temperature.
There are several temperature sensors on the thermostat housing. The one that needs to be tested is the one with the Yellow/Blue and Black/Slate wire running to it. I am looking for the specifications for it now.
Correct but that temperature sensor goes straight to the control module
Correct the module controls the injector on the 90-93 cars.
I know on earlier and other cars it was control by a temperature switch. Which is not the case with this car.
So the temperature sensor can be tested just like a regular cooling sensor it's not a switch
Correct. Are you okay with Celsius or do you want it in Fahrenheit?
And roughly how cold?
I'm in miami so 70 f
So 0C is 6000 ohms 20C is about 2500 ohms
So it should be about 2500 Ohms
At 80C it will be about 200 ohms
K so I tested the sensor if is k what else can cause the module no to send the ground to the injector
Wow Miami you are up pretty late then.
Yes I know but I have this car that I need to fixit
Where are you
I am in San Francisco.
What time is it
There are no other variable given for why it would not give cold start. Yet 70F is pretty warm so it will not give it a 100% shot
It is 9:30
The manual says there is no cold start injector over 60F
So pretty much look this sensor is the problem
O that's no good
this morning I put ground to the injector and start right away
Have you checked fuel pressure?
No fuel pressure but when the car start runs and drive perfect
If you continue to crank it will it start eventually?
After is warm yes
No check engine light? What about exhaust readings? This car also does not use a warm up regulator it uses an electric control valve on the fuel distributor.
No check engine to tell you the truth i don't have the exhaust readings
The valve on the side uses current to add or reduce fuel flow to the injectors. It could be faulty. The base settings could be faulty as well. Will it start if you press the pedal down slightly or the sensor plate?
Fuel pressure should be between 6.2 and 6.4 BAR
ill try with the pedal all positions and the engine no start
you think maybe fuel pressure is low
And this valve goes in which side of the fuel distributor
That is my thought. The fuel distributors rarely fail or come out of adjustment.
You will see the valve, I believe it is on the driver's side. It is about an inch by two and three. it has a two wire connector going to it. To check its operation you have to tap inline with it to measure the amperage flowing to it.
If you have the ability to check CO it should be .9% before the catalyst. If you would like we can leave this open and continue tomorrow as well.
I mean looks like someone all ready work in this car and try to adjust the distributor I mean
Crap, if they messed with the settings it you means you might have to do an adjustment. Is the blanking plug back in the mixture hole?
Because the flat part is drill
Okay because that being out could cause problems, not like this though.
I mean looks drill and have a little plastic plug in there
Not original definely
I know it's complicated for you no looking the car it's complicated but like I said after start run smooth like new
No smoke nothing
I would check the fuel pressure and the idle mixture, both when cold and hot. Then get back to me. I think at this point I can not direct you any further with out one of those two
I would doubt then that the fuel mixture is off. Possibly weak fuel pressure.
K so I talk to you tomorrow
Thank for your help
Tomorrow, sleep well.
Thank you too
Do you have access to this at work? Have you been able to do any tests today?
hello today I try to adjust through the mixture hole just a little bit of half turn clockwise and has been starting well the all day let's see in the morning.
and I have another question there is a level sensor for the rear suspension the car is all up according with the owner someone mess with that can you tell me where is located this sensor
Thanks for your help I appreciated