I have just finished installing a new (used) throttle body which I cleaned and followed all the directions this time. I also put back on a mass air sensor which was also cleaned by recommendations from here. So the engine starts great runs good no check engine light on but the idle runs high like at around 2000. If I put the truck in drive and keep the break pressed down the RPM's drop to around 1000. When I put the throttle sensor back on did I do something wrong? can I adjust the throttle from the unit itself? <img src="/forums/images/graemlins/scared.gif" alt="" />

Quoting from the FSM "Introduction and Master Troubleshooting" section Page 9:

1. Before connecting or disconnecting the negative cable, be sure to turn off the ignition switch and the lighting switch. (If this is not done, there is the possibility of semiconductor parts being damaged.)
2. After completion of the work steps [when the battery's negative (-) terminal is connected], warm up the engine and allow it to idle for approximately five minutes under the conditions described below, in order to stabilize engine control conditions, and then check to be sure that the idling is satisfactory. For 3.0L engine models: If the engine rpm is high, switch OFF the ignition switch, and then, after switching it ON again let the engine idle for 2 or 3 minutes.
This will cause the engine rpm to decrease about 100 rpm, so repeat this procedure until the prescribed idling speed is reached.

Engine coolant temperature: 85 - 95 deg. C(185 - 203 deg F)
Lights, accessories: OFF
Transmission: neutral
Steering wheel: centered

There is also a section in the FSM MPI System starting on page 14-62 for setting the idle speed. Note that there are terminals to be grounded both in the engine bay and on the ECU test harness connector behind the glove box inside the truck.

Eric W.

is this some reprogramming mode that you have to do. Will there be some set minimum that the computer knows?

this does not seem to work is there any other way to adjust the idle

Are you referring to the turn off/turn on sequencing? If so, did you look at the procedure I mentioned after that to set the idle via the idle speed adjusting screw?

If you do not have the Factory Service Manual I highly recommend you go to the Russian site mentioned numerous times here and grab the MPI System pages. Look at page 14-63 and following for the procedure. This section will also contain the information you need to troubleshoot all the other goodies you are interested in such as the throttle position sensor, the idle position switch, etc.

Eric W.

Is there a throttle cable that could be too tight?

i pulled all the cables off to check and it did not make a difference it runs at 2000 rpm while in park and when I shift it into drive it goes to 1000 I have been looking for a copy of the FSM cant find one

Sent you a PM.

Make sure you have sufficient coolant in the system. I found that the idle will be high with low coolant due to the coolant flow thermoststic idle system.

Ed

is there anyway to put the throttle sensor back on wrong? it felt like you had to put it behind the spring and then kinda turn it to get the screw holes to match up