Davis Posted 7May, 2021 Report Share Posted 7May, 2021 Hey all, I have what I think is an issue with the idle. When I start the car it will sit at 1800 RPM and doesn't seem to settle unless I stop the engine for 10 minutes after it's warm, I fire it up after a short break and the idle is back to normal. So the idle wont settle when the engine is running, remains high until I stop it and re start after 10 mins or so. It's like the part that tells the engine to slow idle works but only when it get extra hot when the car isn't running? Thought's Quote Link to comment Share on other sites More sharing options...
OBRUT Posted 7May, 2021 Report Share Posted 7May, 2021 Sounds like a faulty warm up regulator. It’s separate to the rest of the injection system and can be rebuilt in isolation. Quote Link to comment Share on other sites More sharing options...
Graeme Posted 7May, 2021 Report Share Posted 7May, 2021 Might be worth checking the auxiliary air valve. It has an electrical connection that needs to be connected to make it close. If the electrical plug isn’t on or faulty the valve will take a long time to close - causing a higher idle - might explain why it sorts itself out after it is stopped when warm. The warm up regulator could also be a contributor as it creates a richer mixture for the first 3 to 5 minutes from cold. It also has a wiring a plug that should be connected and working. Quote Link to comment Share on other sites More sharing options...
Merv Posted 7May, 2021 Report Share Posted 7May, 2021 What year is the car? On later cars the vacuum hoses are likely suspects or the idle control switch adjustment. Quote Link to comment Share on other sites More sharing options...
Davis Posted 11May, 2021 Author Report Share Posted 11May, 2021 thanks for the responses, the car is a 1980 SC I have some further questions, If it were vac hose leaks wouldn't he idle be high all the time? With the WUR what controls it to turn on and off...if thats what it does? Quote Link to comment Share on other sites More sharing options...
Graeme Posted 11May, 2021 Report Share Posted 11May, 2021 On your 1980 SC both the warm up regulator and the Auxiliary air valve get 12 volts when engine running ie ignition on. The control for both is via the 12 volts and a bimetallic element. When working correctly the WUR fuel pressure will rise as the element heats - so richer with lower pressure and leaner when fully heated. The Aux air valve will be open when cold and close airflow through it as it heats up - it is possible to make some adjustment to both of these components. For the WUR you should have a fuel pressure gauge (connected correctly) to make sure settings are within specs. The Aux air valve opening - it is a slide type valve can be adjusted moderately if it is open when hot. A quick check for both these components would be to make sure you are getting 12v across the wiring plug for each of them (2 pin plug - 1 positive 12v and one negative earth). If you take one of the hoses (~20mm diameter) off the Aux air valve you can see the valve opening if you use a mirror. If from cold it doesn’t close after a while with 12 volts at the plug there is a problem with it. Hope this helps. Quote Link to comment Share on other sites More sharing options...
Davis Posted 12May, 2021 Author Report Share Posted 12May, 2021 thanks for all of the reply's, I removed the 2 pin connector from the WUR and found corroded connectors and also the wires we hanging on by a few strands. I'll start with rewiring that first and let you know what happens. Mike D'Silva 1 Quote Link to comment Share on other sites More sharing options...
Davis Posted 22July, 2021 Author Report Share Posted 22July, 2021 In Iso so found some time to update on this. I replaced this connector above and it immediately fixed the high idle issue. So I guess it was the WUR not functioning that was causing my high idle but rather than having to rebuild the WUR it was just the connector. 🙂 sus911 and Mike D'Silva 2 Quote Link to comment Share on other sites More sharing options...
Mike D'Silva Posted 23July, 2021 Report Share Posted 23July, 2021 Great result! It's a good feeling with you fix something yourself. Quote Link to comment Share on other sites More sharing options...
Coastr Posted 24July, 2021 Report Share Posted 24July, 2021 And I was just about to internet diagnose as broken head studs needing full rebuild Davis 1 Quote Link to comment Share on other sites More sharing options...
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