Falcondrivr

OK long post:
Had the engine out to do the clutch/LWF stuff. While it was out, I did Plugs, wires, rotors & caps, lower valve cover gaskets, cam tower gaskets, removed the SAI system.
All back together and in. Everything runs beautifully except AFTER the car warms up, it idles at 2500-3000 RPM. Also, the Check engine light is on (95 OBD1 car, with OBD2 connector.)

I've done a bit of troubleshooting. Used the carb cleaner spray method to look for vacuum leaks (not the best method, I know) Tried a working ISV to see if mine was bad. It's working.

When I removed the SAI system I bundled the electrical connections and wire tied them ti the old support. I have 2 connectors bundled there. I was pretty sure that they both came off the SAI. But the PET only shows 1 connector on the SAI...I've looked all over in there looking for an empty plug. Can't find one. It's a small 2 way connector with a red and black wire that I'm not sure of.

Also, the PET shows a temp sensor on the airbox. I don't have one, and my airbox doesn't have anything where the PET shows the sensor.

I've run 1 tank of gas through the car since, and noticed 14 MPG, where normally I get 15.5-16 on my usual routes. This could be from the LWF causing me to drive a bit more aggressively , from the high idle while stopped, or maybe the CEL issue?

So, is there something that would set off the CEL and cause the high idle? Or, am I looking at a vacuum leak for the high idle, and something unrelated for the CEL?

My next step is to go pay the dealer $100 to read the CEL code for me. And whatever $$$$ to do a smoke check for vacuum leaks. Does anyone have any other ideas before I give in to the dark side (dealer visit)????

geolab

there are two connectors for the SAI pump on the wiring harness that stay unplugged if no SAI pump

Falcondrivr

Thanks! I thought I was pretty careful, but at this point, I'm second guessing everything I did...

John H

Make sure the wires on the top of the motor are hooked up correctly. I had a gray male in a black female and black male in a gray female (they fit but) the car exhibited throttle/idle issues. They were on or around the throttle body. I know it sounds silly, but it took me forever to notice the color conflict which corrected the problem.

geolab

in this case, there is a known number of alternatives that cause erratic idle
we should go through by elimination...
the only itch I have is maybe there is a trick involved after the removal of the SAI, that could cause the problem,
So the sources of erratic idling:

1- Engine temperature sensor
2- Throttle position switch
3- Air Mass Flow Sensor
4- ISV
5- tank ventilation relay
6- injectors
7- battery ground strap
I will add an 8th that I experienced once
8- throttle cable MAL-ROUTED from engine to gas pedal, throttle position switch mal-informed when engine starts, and ECU is de-regulated
good luck

Vorsicht

Here's my two cents: After I removed the SAI my temp sensor wire got knocked off - You can tell if the temp gauge wont work after warm up.

I also screwed up the electrical plugs that sit in the rear left - One I got reversed. Double check they are they way they were before the SAI delete.

Lastly, you can check the last code thrown by depressing the gas pedal with the car off and the ignition on. depress for about three seconds and when the light comes on remove your foot from the pedal. Then count the series of blinks of the cel light. there are usually 4 numbers that come up in a row and then it will repeat itself. I think code 1500 or 1511 means no codes thrown. give it a try.

John H

here's a pic of where I think the two plugs I screwed up were located. Inside the red circle, I think.

Vorsicht

One more thing. The temp sensor on the airbox is a 96-98 thing, 95's don't have that.

Falcondrivr

Temp sensor works. I tried the cel code read by the method below, and my cel never flashed. I'm wondering if my throttle position switch is the culprit?

Vorsicht

try it again and keep your foot to the floor until it flashes, then take your foot off.

Also, is the ignition in the "on" position?

Falcondrivr

I
Tried it just like that. Waited 4 minutes. Mine never flashed.

Vorsicht

Ok, I just went down to my car to make sure I am explaining it correctly. To be more clear, you must turn the key to the second position where all the gauge lights come on and then do the pedal thing.

If this does not do it something may be amiss electrically and you might have to go to the stealer for a code readout. They really should do it for free!

Falcondrivr

I'm doing the procedure correctly. The car must sense wot to initiate the flash. Mine isn't flashing. That's why I'm suspecting the throttle position sensor.

Vorsicht

Could be. I don't know how to check if it's bad other than to make sure it's connected and or a code readout. Good Luck

rsr91128

Rick,

If you are going to spend $100 to have the codes read, I would probably just buy a Durametric cable or the homemade one on the 964 board. It would pay for itself pretty quickly.

With that you can see which sensors are working.

If your throttle cable is not adjusted correctly you will not trip the WOT sensor. You can have someone manually hold the throttle wide open when you turn on the key to see if the codes read out. If it works then, you just need to readjust the cable.