5000cs cold/start problem [Archive] - Audi Forums

: 5000cs cold/start problem

01-24-2010, 07:42 AM
1987 5000cs quattro sedan, no mods, as is factory. Have hesitation or miss while under load, especially during climbing hill in 4th or 5th. When ever I unplug (electrical-blue) conn to cold start injector everything is a-ok, no hesitation .
All other functions ok, no surging at idle.
update, went for test drive cold start unplugged all was well then after about 20 min of driving car died. Instrument display showed picture of gas pump. re plugged in cold start no difference no start, display shows picture of gas pump. ran output test along road side ,fuel pump is running but at what pressure I have not checked. what is a good pressure and where best to check it? Could this be coincidental that fuel pump has gone weak?

01-25-2010, 05:45 PM
hello anyone there?

05-29-2010, 07:42 AM
:)Oh Dear God the 5000, the bane of Audi since it first started running over people, how I miss you and 100 models, good times... actually, just the 4000s, that car was insanely good to drive further details please visit OEM auto parts (http://www.autopartspoint.com/)

Harvey Smith
09-18-2010, 04:21 PM
When your fuel pump is getting plugged up from a dirty gas tank or just a batch of bad gas it will typically start to growl. If that happens you will need to remove your pump from where it's located in your gas tank and vacuum out the screen. If the screens dirty you will also need to clean your tank from top to bottom and get rid of the bad gas. Tank access is via trunk.

06-06-2011, 07:16 PM
I am open for all opinions. Since it runs great at high rpm I figure pump and screen are good? I have done fuel pressure readings all over the car and compare them to my orther 87 quattro both match. Where is a good buy on injectors?

06-11-2012, 12:37 PM
It is not starting when cold since the cold start valve is not functioning. 1-It could be a coolant temperature sensor gives a wrong resistance readings when it cold so ECM doesn't know to send a signal to turn on the cold start valve. 2- It could be a bad cold start valve. I doesn't open even the ECM send a signal to it to open. You can see that Ohm reading on the terminals of the cold start valve is good, but it is still bad since your measuring the coil to open a valve showing the coil is good but valve gets stuck could not be opened. Good luck in checking these out for a good replacement..

07-28-2012, 11:14 PM
You can send injectors to Jaguar Fuel Injection service in Florida. The guys name in Dave Faircloth. He can clean CIS injectors, and the CS injectors as well.Sorry, I don't have his contact info here. I have used him many times, as am a happy customer.

Jesse in Rockville