Help, I have a high Idle problem. Options

[sweathappens]

I have a 74 2.0. I just finished changing engines and I am having trouble getting the engine to idle normally. I set the dwell and timing and it is idling at over 2000 rpms. I don't hear any vacuim leaks. I can't figure out why I can't get this thing to idle correctly. I have used a 75 2.0 distributor for many years and it worked fine. Could this be the problem? How do you tell a 75 distributor from a 74? When I remove the vacuim line from the pressure sensor, the engine idles better but seems to start burning rich. I'm baffled. Any suggestions?

I took the car for a ride even with the high idle and it seems to run great. If I can just get this thing to idle right, I can move on to other issues with this car.

[r_towle]

Check the TPS switch, make sure its set right. It can cause this.
check the accel cable, make sure it set right. obvious, but could do it...and you need a goo strong spring.
Check the idle screw on the throttle body, bottom that out all the way.
Once you check those, if the idle screw is bottomed out all the way, you have a vacuum leak.

Rich

[sweathappens]

Check the TPS switch, make sure its set right. It can cause this.
check the accel cable, make sure it set right. obvious, but could do it...and you need a goo strong spring.
Check the idle screw on the throttle body, bottom that out all the way.
Once you check those, if the idle screw is bottomed out all the way, you have a vacuum leak.

Rich

Thanks! What and where is the tps switch?

[r_towle]

AHA..

OK,
TPS is throttle position switch.
First, lets go through what you have done.
The dwell needs to be set perfectly on this motor, not close enough.
The timing needs to be set while at 3500 rpms.

If and only if that is perfect will anything else make a real difference.
The TPS.
Take off the air cleaner assembly.
Now you are looking at the throttle body.
On one side the throttle cable hooks up.
On the other side is the TPS.
It has two screws, one on either side that you just loosen, dont take them out...and you can rotate the TPS a little bit in each direction.
Once you think you have it right, turn key on, be quiet.
Get you head inside the engine compartment.
Be quiet
slowly turn the throttle while you listen for very small clicks of the injectors. Count the click..I cant remember...but I think 21 is the magic number you are listening for.

Its important to have a click as soon as you move it...and be able to go all the way through the range to WOT and have all the clicks...
Look at the pelican parts web site, there should be a technical article...
Or go to Brad Anders site on the Rennlist (search google for brad anders and djet) he talks all about djet and how to tune it.

Its well worth the time to read his site.

Rich

[sweathappens]

AHA..

OK,
TPS is throttle position switch.
First, lets go through what you have done.
The dwell needs to be set perfectly on this motor, not close enough.
The timing needs to be set while at 3500 rpms.

If and only if that is perfect will anything else make a real difference.
The TPS.
Take off the air cleaner assembly.
Now you are looking at the throttle body.
On one side the throttle cable hooks up.
On the other side is the TPS.
It has two screws, one on either side that you just loosen, dont take them out...and you can rotate the TPS a little bit in each direction.
Once you think you have it right, turn key on, be quiet.
Get you head inside the engine compartment.
Be quiet
slowly turn the throttle while you listen for very small clicks of the injectors. Count the click..I cant remember...but I think 21 is the magic number you are listening for.

Its important to have a click as soon as you move it...and be able to go all the way through the range to WOT and have all the clicks...
Look at the pelican parts web site, there should be a technical article...
Or go to Brad Anders site on the Rennlist (search google for brad anders and djet) he talks all about djet and how to tune it.

Its well worth the time to read his site.

Rich

Rich,

Thanks. I didn't have this problem with my old motor. Can a new motor cause this type of problem? I am using a dietributor off a 75 2.0. Might using the wrong distributor cause my problem? I got to go now . I'll look in tomorrow morning.

[r_towle]

Distributor should be the same...

But you may have fudged something up in the FI system.

Keep hunting.

Rich