Step-a-toe Posted September 22, 2020 Share Posted September 22, 2020 Vacuum leak to the inlet manifold environment is not going to make it run hotter unless an air leak is leaning mixtures beyond ecu control. Have a look at the throttle body, there is two additional idle air bypass circuits that allow air to bypass the main throttle plate. I think your passenger side ( I like to express as turbo side ) of TB is a flat screw head, flat blade slot type. Not supposed to adjust it. Dizzy side has a solenoid controlled air bypass and sealing rubbers n stuff you can't buy no more. Ideal not to touch this either but no harm hitting both regions with spray lube or leak a little butane to see if idle increases due to air fuel enrichment. Anyone with a parts manual may be able to help see if these had auto and manual throttle bodies to give different characteristics for auto copping load change from N, P to D or R Quote Link to comment Share on other sites More sharing options...
SiriusBlack Posted September 23, 2020 Share Posted September 23, 2020 (edited) Well, I just got done fiddling with it some more. I tested both of those air valves for leaks and they didn't have any. I tested and replaced the vac line from the manifold to the tranny, with no result. I noticed that if I turned the air valve screw on the turbo side in increments of quarter turns it made small changes to the idle speed. I got it to idle a bit longer when in gear, but the moment I put it in gear the engine struggles for probably 30 seconds then dies without increasing the throttle. I also removed and cleaned the turbo side screw and cleaned it. So once again I'm out of ideas, it's truly baffling. Some research I've done seems to suggest it could be a dirty or faulty IAC valve. Anyone know if that might be my problem? Also I have a general idea, but where is it located? Any other suggestions would be great. Edited September 23, 2020 by SiriusBlack Quote Link to comment Share on other sites More sharing options...
DaveT Posted September 23, 2020 Share Posted September 23, 2020 I don't know turbos.... But I have had a won't run at idle problem on an EA82. The wire that powers the IAC valve had a break in it. When it would go open, the car would not idle. I had to feather the gas to keep it going. Quote Link to comment Share on other sites More sharing options...
SiriusBlack Posted September 24, 2020 Share Posted September 24, 2020 I'm thinking it's most likely the Idle Air Control valve that's causing my problem. Can anyone tell me where it is? I know where the EGR solenoid valve, the Aux air valve on top of the thermostat housing and the fast idle solenoid for the AC is. I just can't seem to find the IAC valve, only post i found that came close to telling me said it was under the power steering resevoir and difficult to get to. However i looked and there doesn't appear to be anything resembling a valve there. Please help, this is driving me nuts! lol Quote Link to comment Share on other sites More sharing options...
Step-a-toe Posted September 24, 2020 Share Posted September 24, 2020 (edited) Idle air control Valve Sort of have two with that function and you have blocked the first one off being the jigger on the thermostat Your second is on the dizzy side at the back of TB next to the screw you removed and cleaned. Some years had a two wire solenoid, one being for an earth. Pictured is my single wire unit. These really only increase revs a little to cope with load when AC is on. I don't think these turned on under power steering pump load. I use mine just for a faster idle on start up in colder months below 5°C with dedicated propane Impco fuel system. Just read the rest of your post The one a post describes as being under or behind PS pump is likely for the spider inlet as these deleted the thermostat mounted cold starting bypass valve. Have we discussed fuel pressure and injector cleanliness? Timing? You have covered: egr valve trans vac line idle air adjust screw fast idle control solenoid cold start air bypass on thermostat Pretty much it except the vac line from front of throttle to distributor vac advance can. Every one of these I have had have not held vacuum and inturn won't retard timing on boost. With propane air mix in my inlet I used to blow a little charge into the distributor body, match ( no pun yet) this with a little spark that was supposed to hop from rotor button to terminal inside, I didn't get boost , I got BOOM ! Took five months to resolve, marshmallow valve springs got initial blame Edited September 24, 2020 by Step-a-toe Quote Link to comment Share on other sites More sharing options...
Step-a-toe Posted September 24, 2020 Share Posted September 24, 2020 Doesn't a worn distributor shaft bushing cause idle fluctuations? Time to unscrew the cap and give it a feel Quote Link to comment Share on other sites More sharing options...
Step-a-toe Posted September 24, 2020 Share Posted September 24, 2020 Maybe time to blame the auto trans components? Quote Link to comment Share on other sites More sharing options...
SiriusBlack Posted September 24, 2020 Share Posted September 24, 2020 I have triple checked my timing, both valve and ignition. I will double check my disty. I also talked to someone that suggested that if my main throttle butterfly is dirty, it can mess with how it closes. I'll try cleaning it thoroughly and see if that helps. 1 Quote Link to comment Share on other sites More sharing options...
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