whitelightning74

I have a 93 mustang and I cleaned the trottle body just like it said in the sticky article on this forum. I also to the IAC valve off and it had lots if carbon in it. I cleaned it the best that I could. I reinstalled everything and then check the tps volts and it was right were it should be. My problem now is that the car will not idle low enough. I idles around 1900 rpm and I cant get it down any. I even disconnected the ngative battery cable for 30 or so minutses and stiil the same. I went and bought a scanner and here is the codes I got but I dont think any of them relate to the idling problem but here they are. Key on engine off =85 canister purge circuit failure or transaxle error 3-4 / 4-3 shift solinoid circuit failure. Key on engine running test revealed=41 no exhaust gas oxgen switching detected-always indicating lean. This car was idling at about 1200 before the clean. It has never had the egr vacum hose on it since I have owned the car. Soon has plug that in it idles terrible so I assume that wy it was unplugged when I got it. The car has long tube bbk headers and the smog stuff is all gone. What do I do now to get this dang idle to come back down. Any ideas. I know yall could help. Thanks in advance

5.0stanger

Turn the idle screw down and re set TPS

mattdel

sounds like an intake leak to me, probably the IAC gasket.

88blackgt

+1, it should be on the tb

whitelightning74

I did have the idle screw turned so that it just makes contact and the tps was 98 . The iac is what I unplugged and tried to adjust the screw but it done seem to do anything

whitelightning74

Whats a good way to check for leaks?

CrazyCobraSpeed

i had a similar problem i had done a lotta bolt on mods at once... i had to go get it take to a tuner and her work on it... it was to lean at idle he said be she runs great now... he did a great job... and he only chnage 500 bucks... and did a lot more than just tune it...

88blackgt

spray something like carb cleaner on vac lines

look for bubbles

whitelightning74

Update, I went out and checked for leaks by spraying all around with tb cleaner found nothing, I then checked the tps again and set it at exactly .98 and still nothing. I did drive it for about 4 or 5 miles and now its still idling at 1500. WHat now Guys??????

whitelightning74

Also guys what about the egr. I know it was not doing it before I cleaned the tb but I also cleaned in the intake some and there was all kinds of carbon that came out of the egr opening. It was disconnectd when i got the car but I hooked up a vacum hosewas next to it that had a steady vacum to the egr and I can see the egr valve inside move and the car just about shuts down and idles very very rough. So I just unhooked it. What could this cause?