| Author | Message | ||
     CHO SHU PUI DANNY Yet to post message Username: dnadanny1 Post Number: 1 Registered: 05-2019 |
Hi there. When the engine is cold every morning, the car's idle too slow that I need to press the pedal to keep the engine running. Therefore, I think there is no fast idle. And, there is idle when the engine warmed up. Could anyone give some suggestion to me on how to fix this problem? Any comment and suggestion will be appreciated. Thanks a lot. Regards, Danny | ||
| michael vass Grand Master Username: mikebentleyturbo2 Post Number: 563 Registered: 07-2015 |
Hi danny what model do you have? | ||
| David Gore Moderator Username: david_gore Post Number: 3331 Registered: 04-2003 |
Welcome to our forum. I am assuming your engine is fitted with carburettors and not fuel injection and is a Hong Kong delivered vehicle. It is important for us to know the model and year of delivery plus the chassis number off the identification plate fitted on the bulkhead in the engine bay. Once we have this information, we will be able to help with more specific information relevant to your vehicle. | ||
| Omar M. Shams Grand Master Username: omar Post Number: 1816 Registered: 04-2009 |
it is a 1993 car I assume. | ||
| David Gore Moderator Username: david_gore Post Number: 3335 Registered: 04-2003 |
Omar, This is where it can get difficult with export model variations for particular markets - a 1993 car exported to your part of the world may well be different to a vehicle exported to Asia depending on local vehicle compliance laws at the time. . | ||
| Omar M. Shams Grand Master Username: omar Post Number: 1817 Registered: 04-2009 |
Yes Agreed David. Danny, can you please send us a photo of the engine compartment from both sides? Thanks | ||
| Roderick Waite Prolific User Username: rodwaite Post Number: 228 Registered: 01-2012 |
Hi Danny, all that has been said is correct, to be sure we're talking about the right car. I would have expected a 1993 built car to have fuel injection, but that may not be the case, it seems. If SU carbs when starting from cold, you must first press the accelerator all the way to the floor, once. This action sets up the choke. Then turn the key and the engine will start at a fast idle (around 1000rpm) due to the choke. By the time the brake pressure warning lights have gone out, a quick blip of the accelerator will usually drop the revs enough to avoid a thump when engaging Drive (foot on the brake anyway) and off you go. Provided we're talking about the same car, of course. My Spirit is a 1984 build ... | ||
| CHO SHU PUI DANNY New User Username: dnadanny1 Post Number: 2 Registered: 05-2019 |
Thanks all your help. And,sorry for not not giving sufficient information. My car is RHD 1993 Royce Rolls Silver Spirit II , the fuel system is KE Jectronic.(VIN:SCAZS02A5PCH46132) And I will post the photo of the engine compartment later on. Thanks again. Regards, Danny | ||
| Omar M. Shams Grand Master Username: omar Post Number: 1821 Registered: 04-2009 |
Dear Danny, We will wait for the photos - but in the mean time there would be two things I would look at. First is the coolant temperature sensor (the one that sends information to the ECU not the one that shows a reading on the gauge) and secondly the idle air control valve. A question for you: Did this problem just happen one day or did an intervention or event take place that resulted in low idle speed when cold? | ||
| CHO SHU PUI DANNY New User Username: dnadanny1 Post Number: 3 Registered: 05-2019 |
Here are the photo of the engine bay. And sorry i do not know where is the coolant temperature sensor, and how to check the idle air control valve. BTW, the idle air control valve just replaced a year ago.   . | ||
| CHO SHU PUI DANNY New User Username: dnadanny1 Post Number: 4 Registered: 05-2019 |
Are these the coolant temperature sensor and idle air control valve?   | ||
| Omar M. Shams Grand Master Username: omar Post Number: 1822 Registered: 04-2009 |
Dear Danny, you are correct about the idle air control valve. But the coolant temperature sensor is not the one you have shown us. Here is what it looks like..... https://www.ebay.com/itm/Coolant-Temperature-Sensor-Rolls-Royce-6-8L-including-Flying-Spur-Turbo-/301714709136 . | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2166 Registered: 09-2004 |
If the coolant temp is ok ie sensor resistance within ohms spec 30c= 1300-3600 and at 80c= 250-390 ohms then the idle speed can be set but not on a really hot engine by the adjustment on the air control valve. However after the idle CO is set first and other checks if needed. | ||
| Robert J. Sprauer Grand Master Username: wraithman Post Number: 440 Registered: 11-2017 |
Your car may have a warm up regulator that is mounted on the intake manifold. They sense block temp and adjust the idle when cold. It's an electrical sensor that works with the ECU. There is also another sensor that feels the coolant temp and that is also fed into the ECU. I have a similar FI on my 1980 Silver WraithII. My system also has an idle set screw. If you are not familiar with this system do not tamper with it. Read the Bosch supplement that is available. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2167 Registered: 09-2004 |
Robert unless I am mistaken you are referring to the "K" Jetronic system! This is the "kE" system. As for the ECU testing inputs first engine speed [distributor] engine temp [sensor] sensor plate position [pot] throttle position [switch] And then much more. You get the picture and this is old school by todays fault codes. |
