chicows18

I have a 4 cylinder SVO. It was running like a champ. Did a basic tune up which included all the necessities (Spark plugs, wires, cap, rotor, pcv, oil filter, air filter, fuel filter, etc) and now the car wont idle at all. It will turn on and sound strong when you accelerate but for the life of me, it wont idle at all. If I let go off of the gas, the car dies. So I was thinking maybe the timing needs to be adjusted, but i dont know how. It says on the stickets inside the engine bay that I should disconnect something and adjust according to the specs. The only thing I see is two wires with a jumper by the distributor. I take the jumper off but it doesnt do anything. Then at the specs it also says to disconnect the idle valve on the throttle body, so I do that and still nothing happens. I tried adjusting according to specs with the above mentioned but nothing. So can someone please tell me exactly how this is soppose to be done. Pictures would be helpful.

chicows18

anyone?

chicows18

From reading this forum, it looks like you have to disconnect this plug



I did already but now my question is if the idle is suppose to increase or decrease when this is disconnected. Also, if the IAC on the throttle body is not working, would this not allow the idle to maintain?

evintho

Yep, that's theSPOUT (Spark Out) connector. Pull the greypiece out. That willdisconnect your SPOUT. Put a timing light on it and time to 10*-12* BTDC. Don't forget to reinstall the SPOUT after timing! I hope you installed only Motorcraft tune-up parts! Our cars respond very well to them. I know that sounds dumb but believe me, it's been documented a million times. Use Motorcraft tune-up parts, only!! Your IAC may be gummed up. Take it off and spray BrakeKleen, liberally, inside the IAC body to free it up.Now would also be an opportune time to adjustyour TPS.

Idle / TPS Adjustment


This article is intended to teach the basics of adjusting the idle and the Throttle Position Sensor on the 2.3 liter Turbo Coupe Thunderbird. It is recommended that your engine have a good tune up before you attempt to make any changes.

Tools Required

· Voltmeter with a DC voltage scale.
· Short Phillips screwdriver.
· Small adjustable wrench.

Components Involved

· Idle Air Control (IAC).
· Throttle Position Sensor (TPS).
· Throttle Body.
· Accelerator Linkage.

Adjustment Procedure

· First bring the engine up to normal operating temperature
· Turn the engine off and unplug the Idle Air Control connector from the IAC. This is located on the backside of the Throttle Body near the firewall. This device is a round cylinder approximately 5 inches long with a (2) bolt flange and 3 wire male / female plug connector. (see picture)
· Start Engine. Using the small adjustable wrench on the idle adjustment screw, adjust the base idle to 700 – 800 RPM. (The idle adjustment screw is #1 in the picture below)



· Locate the Throttle Position Sensor (TPS) on the Throttle Body. This is also located on the backside of the Throttle Body near the firewall. This is a black plastic device with (2) screws that allow adjustment and (3) wire male / female connector. (see picture)



· Back probe the back of the TPS connector to connect the meter... The + (positive) side of the meter connects to the green wire. The – (negative) side connects to the black wire (SIGNAL RETURN). NOTE: you must connect the negative side of the meter to the black wire (SIGNAL RETURN). Do not just ground it to the chassis; it’s not the same thing. Back probing means sticking pins down the back side of the harness side of the connector for the appropriate wires. It can be tricky but is better than sticking pins through the wire insulation. The connector is left attached to the TPS.
· Using the small Phillips screwdriver to loosen the two hold down screws slightly, then rotate the TPS to change the voltage setting. Adjust the TPS output voltage to just under 1.0 volt. Most turbo tuners find that setting TPS voltage to around .90 - .95 volts works best. I set mine around .94 volts. When set, tighten the screws and recheck the reading.
· Turn off the engine.
· With the engine off, but key ON and the voltmeter still connected move the throttle linkage slowly from idle position to wide open and back to idle, looking for a steady increase and then decrease in voltage without any voids or dead spots. Any voids or dead spots would indicate a faulty TPS.
· Plug in the Idle Air Control.
· Start the engine. The engine’s idle speed should settle in around 1000 RPM.
· Take the Turbo Coupe for a drive and see how she runs.

This information is provided to you as a courtesy from the North American Turbo Coupe Organization (NATO). The user(s) of this information bare sole responsibility for its use and their own actions. The Author, NATO, or its members assume no liability.

plazma

Also be sure to check that the IAC didn't come unplugged. It's the cylinder shapes peice that sits about the tps. It controls your idle and the plug on it is known to break so make sure yours is plugged in.

chicows18

I tried cleaning the IAC but nothing. The car starts and then just turns off as soon as I let go of gas. Does this mean that the IAC is not working and should be replaced?

plazma

How does it run when you hold down the gas a bit? If it's jerky and unhappy then you have some problems if it's normal then just make sure the iac is working and use the tb throttle screw to open it a bit.

chicows18

When you step on the gas it works just fine. It has to be something with the IAC. But I replaced it with new one and still nothing.......anything else I can try?

crono61

i vote sticky on evintho's write up

sleeper_inc

I don't think thats evintho's write up, went on a site and it was the exact same so....