Ok, I need some advice. My car is an '83 TA, 5 speed LG4, 61k miles. I'm the original owner. It's mostly stock, except for a Banks low restriction exhaust system (from headers back) and some chip (I think ADS, but it was 35 years ago so who knows). I've worked through a recent bout of poor (extremely rich) running - due to a large mouse nest in the air cleaner snorkel and a bad TPS. So those issues have been largely addressed - set the new TPS to around .5v at idle, replaced CTS, plugs (3 times as they kept getting fouled), wires, distributor cap & rotor, O2 sensor, CT sensor, fuel filter, PCV, replaced most of the vacuum lines, replaced stuck open thermostat. Choke appears to be working correctly, wide open when kicked down.

The car is now running well, except... it wants to idle around 1300 instead of the 700 noted on the emissions label. The carb idle adjustments have never been touched. I haven't changed the MAP, but that's about the only sensor I haven't changed. When I run WinALDL, it gives me a MAP voltage of 4.3-4.4v or so, I don't know if that's telling me anything.

Anyway, any advice on what I can try? I've read other threads suggesting a vacuum leak somewhere, but as I've replaced most of those lines to no effect, I don't know where to look.

Comments appreciated!

Thanks,
Steve

 

Of course, you ARE using a diagnostic tachometer for the check and adjustment, and not that in-dash "instrument" from the factory, right?

 

Well... Mostly the dash. But engine speed reported by WinALDL pretty much agrees with it. And it definitely sounds higher than it needs to be.

 

For the record, I replaced the MAP sensor and my idle is now normal.