cold start problems
#1
cold start problems
Guys, my '89 80 won't start up until I have tried like 6 times and then I have to keep my foot on the gas so that it's idling at about 2000 so that it warms up. If I don't do that, it usually just stalls out. The colder it is outside, the harder it is. In the summer, I don't have problems with starting.... Does anyone have any ideas on what might be wrong? Thanks!!!!
#2
There is a thermotimeswitch/temperature sensor (whatever name) and a cold start valve.
The NTC temperature sensor is on the bottom of the coolant flange on the Left side of the head. the cold start valve is that fuel injector that is right after the throttle body.
The temperature sensor measurethe coolant temperature and operates the cold start valve to add fuel for the approite length of time. The temperature sensor uses resistance to measure the temperature. As temperature goes up resistance goes down.
At like 60degrees F there should be like 2500 ohms and at operating temperature there will be like 200 ohms. If it does not operate as such it needs to be replaced.
The cold start valve uses 9-12 volts to open. You can remove it and use a 9volt battery to test to see if it sprays. With the connector flat and facing towards withthe groove on top the left tab is positive. Spray the jet into a jar for safety. The ECU will spray the jet for upto 12(super cold)
Check for a disconnected plug on either component. Then check the ohmage. Then check for a fault code on the Diagnostic memory. If you do not have a bentley I can get you some direction, ask.
I know one of the wires that goes from plug to plug should be continuous. I also think the temperature sensor gets like 12volts but this may not be the exact amount.
I had this problem before because of a broken plug. Check this and let me know.
Dave
1990 audi 80
86 coupe GT CE
The temperature sensor measurethe coolant temperature and operates the cold start valve to add fuel for the approite length of time. The temperature sensor uses resistance to measure the temperature. As temperature goes up resistance goes down.
At like 60degrees F there should be like 2500 ohms and at operating temperature there will be like 200 ohms. If it does not operate as such it needs to be replaced.
The cold start valve uses 9-12 volts to open. You can remove it and use a 9volt battery to test to see if it sprays. With the connector flat and facing towards withthe groove on top the left tab is positive. Spray the jet into a jar for safety. The ECU will spray the jet for upto 12(super cold)
Check for a disconnected plug on either component. Then check the ohmage. Then check for a fault code on the Diagnostic memory. If you do not have a bentley I can get you some direction, ask.
I know one of the wires that goes from plug to plug should be continuous. I also think the temperature sensor gets like 12volts but this may not be the exact amount.
I had this problem before because of a broken plug. Check this and let me know.
Dave
1990 audi 80
86 coupe GT CE
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