1.7 High-idle: set screw all the way in...suggestions?

[MarkRobinson]

this is on my 1.7l, with a good used TB swapped in for my lousy worn-out original unit. Any suggestions?

With the screw all the way in, it idles at 2k. When I start backing the screw out, it indeed increases the idle, but why's it idling so high anyway? I did set the TPS per the link off of PP earlier, before I installed it. In fact, I did it twice.

Thanks! Mark.

[Tobra]

How are your vacuum lines and the throttle body gasket?

[MarkRobinson]

all new, all good> I went through & replaced/fixed/set everything: sensors, gaskets, plugs/wires/disty/points/trigger/cap/rotor/gaskets/head temp sensor/cleaned the grounds/new fuel lines/rebuilt injectors/used (good) TB, new vacuum lines, tested MPS, decel, AAR.

[Dave at Pelican Parts]

You still have a vacuum leak somewhere.

Either that or your timing is way, way advanced.

--DD

[MarkRobinson]

Timing was dead-on last I checked it: will check it again tonight.

Are there other hidden areas for vacuum leaks?? I have new lines, greased TB gasket, new hoses everywhere, tested MPS/decel/AAR & good compression.

[BK911]

Throttle linkage?

[RandyLok]

Yes, there are several other places for potential vacuum leaks. Follow the path.... Starting at the head, you have injector seals, phenolic block between head and intake runners, intake runner boots/seals between there and plenum, possible cracked plenum, gasket between plenum and throttle body, tons of vacuum hoses, aar, around butterfly/pivot, etc.

[Tobra]

No offense meant, but are the vac hoses hooked up right?

[MarkRobinson]

I've replaced all gaskets & even greased (for a better seal) the TB gasket. Intake manifold gaskets are new & clean, intake boots are clean, all vacuum lines are new, & both new lines to the disty from the TB are of the same size on each port: ie, there's one 3.5mm line from the vertical TB vacuum port tp the top port on the disty, & the larger line (4mm?) is on the TB horizontal port, going to the lower vacuum port on the disty. Here's a little list of all I've done:

*Timing is at the red tick mark @ 3500 w/both vaccum lines removed/plugged on the disty
*Disty is rebuilt with good diaphrams in the canister
*All vacuum lines are new good, vacuum is 14" at idle, quickly zero's when throttle is blipped
*Intake boots are fresh, intake manifold gaskets are new
*Fuel injector seals are new, EFI lines are new
*Compression: 125, 127, 128, 130 on a stock 1.7l d-jet
*TB recently replaced with a good used oned: bypass ports were/are clear, idle-set screw is all the way in, & does raise idle further if loosened.
*TPS was set via ohm meter off the popular Pelican Parts forum reference
*if Disty is retarded to get idle down to 1k, car will not rev, just bogs