problems increasing idle - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

qwikcorty · 08-12-2003, 03:19

id like to increase the idle on the ea to about 7-800 so it sounds nicer, and gets rid of the hunting.

when turning the idle screw it get to a point and then the isc must open up, and puts idle to 1200. is it the tps sensor that i am tripping or the map?
i can drill the tps sensor and rotate it hopefully.
if i do this, would i then be able to up the idle screw more?

Rollin · 08-12-2003, 05:30

you have to put the car in diagnostic mode to set the base idle i think (you do in EB, dunno much about EAs).

do this when it is warm:

turn the ignition off, then put it in diagnostic mode, (someone else will have to tell you how, i only know EBs really) then unplug the ISC motor connector.

start the car and let it idle (if it does) you will need to get "normal" voltage readings for the throttle position switch first.

wind the idle up while at the same time turning the TPS in the same direction as the throttle plate to keep the TPS reading the same, try to get it to idle at the speed you want.

get it right, turn it off, reconnect the ISC and see how you go.

if you wind the throttle plate too far without adjusting the TPS the car will think that you have your foot on the throttle and it wont try to idle, thats probably your problem now...

qwikcorty · 08-14-2003, 03:36

if i just leave the isc disconnected, will it bugger up the ecu? will it run differently?
found out somfing tonite too, i thought my idle was hunting cos of the isc opening and closing, but its not. its the fueling i think, running lean rich lean rich, weird eh?

mongrelEB · 08-14-2003, 04:40

If you disconnect the ISC it should not idle, or if it does, at very low revs.
Maybe you need a new ISC?

How do you know the fuel's doing that?
Possibly the pressure regulator, or MAP maybe...

mongrelEB · 08-14-2003, 04:43

Actually having said that it's probably a varying signal from the TPS - happens when they're stuffed.

9psi EB · 08-14-2003, 08:13

I think if you up the idle too much, the ecu may retard the timing to bring it back down to the preset value in the ecu, im not sure on this.

Soxx · 08-14-2003, 16:32

It should be idling at 700rpm anyway.
Adjusting the screw to increase idle is not the answer as the ECU controls idle speed.
I suspect something else is wrong for it to be hunting.
Generally hunting is caused by to rich a mixture.
Something else like ignition timing could be out, or you may have a small vacuum leak.

Rick.

qwikcorty · 08-15-2003, 00:55

ive got a digital led display to watch fuel mix, i unplugged the isc. didnt run untill i turned up the idle. no vaccum leaks, and timings perfect.

looks like im up for some sensors. what is there... tps $?, isc is $150 from ford, map $?, and water temp $32! should sort it out. oh and xr6 fuel reg. thatl do it.

ontop of the alternator i need as it went kaput yesterday. the brushes have worn through the copper on the shaft through to the steel!

EA SVO · 08-18-2003, 05:43

Rob Herrod has a great little alloy plate that goes between the idle speed control unit and the throttle body (MPFI only) it has two grub screws that bypass the control unit and allows more air to pass over which increases the idle and stops "hunting". I have been using this since I put in a Wade cam that dropped the vacuum from 20" to 12". The idle before this plate was all over the place from 300-800 rpm, it sounded like it had a monster cam it! but was on the verge on stalling.
I have set the idle now to 800rpm and it still "hunts" but only +/- 100rpm

qwikcorty · 08-19-2003, 02:18

how much how much how much? gotta picture? what kind of wade cam did u get? mmm 12" of vaccum