DIY: Service your Idle Speed Control (ISC) Unit
Posted: September 1st, 2012, 8:27 pm
Hey guys, if your Idle step up motor acts up as in you start getting a very low idle and sometimes even stall at idle with the AC on, then heres a tutorial vid you can try.
I tried it 2 weeks ago and it corrected my problem thus far.
A new unit can cost you roughly $4000. Jus be very careful when attempting.
I personally found it a little difficult at two points in the vid and I will try to help you through it.
Heres the vid, unfotunately its not in english but you can see what he does.
Heres what you will need:
A Philips screwdriver
A towel
WD40
Liquid wrench spray (if not try some WD40)
A Birdbeak Pliers
A regular Pliers or Vice Grip
Electrical Contact Cleaner
To remove the ISC on a 4G18 engine look under the throttle body and you will see a black unit, with a 6 wire electrical connector. Unplug the connector and remove the 3 phillip screws that keeps it bolted to the throttle body. Clean out the area in the TB after you removed the unit by spraying some Electrical contact cleaner on a cloth and wiping the insides as far as you could reach.
It seems like he did this alot to this unit. Bet your dollar, your unit wont be as easy to dissemble. Take your time, dont squeeze the brown part too much it will break part.
Also theres an O-ring around the surface of the ISC that bolts to the TB, take it out an keep it safe.
0:00-0:26 He's explaining that the brown part is locked into the unit.
Start by spraying Liquid wrench into the 3 holes he pointed to at 0:08
Use the Birdbeak pliers and place it over the spring in the space between the brown part and black bolt looking piston. The object here is to pull the piston out some more, away from the motor.
So hold on the unit with your left hand, bird beak over the spring, and pull outward, the piston should move a lil bit...that should be enough
0:26-0:30 Problem 1: No you cant turn that with your hand, you will need a pliers or vice grip and a cloth. Please do not squeeze the pliers YOU WILL BREAK THE BROWN PART. Rotate the brown part anti-clockwise like the guy did.
0:30-0:45 You will now see 3 brown notches in the 3 holes you sprayed with liquid wrench.
0:45-0:58 Problem 2: No it will not come out that easily, you will have to wiggle and pull. If you find that its not coming all the way out to unscrew the brown part then you need to do the part with the bird beak pliers again, that will free up space for the brown lock to rotate.
0:58-1:12 The object here is to hold onto the brown part and rotate the entire motor so it will unscrew and detach.
1:12-1:17 Take this time to clean the insides of the brown part, spring and black piston with Electrical cleaner.
1:17-1:38 Do exactly as he did, make sure and use the towel and a pliers or vice grip.
If you not getting it out, spray a little Liquid Wrench.
1:38-1:53 The guy is explaining that the silver ring needs to rotate freely, if you try rotating yours it may feel a little gritty. Spray it with some Electrical contact spray and clean, clean everything with the contact spray, even the rest of the housing. The contact spray will self dry.
When the motor itself is clean and dry, spray some WD40 where the guy sprayed his.
Primarily on outer edge of the silver ring. Make sure its lubricated and spinning freely.
DO NOT spray it in the ISC housing, I left mine clean and dry.
Mounting back up:
2:35-2:40 Replace the motor back into the housing as snug and far as it could go.
2:40-3:05 Re-fit the spring into the brown lock and black piston and screw it back into the motor
Hold onto the brown lock and keep turning as snug as possible until the 3 notches on the brown part lines up with the holes on the ISC housing.
3:16 Push back in the brown housing, then push back in the black piston too.
3:19 rotate the brown lock clockwise for it to lock back in place.
My only recommendation if you want is to use a caliper gauge and measure the gap between the brown lock and black piston by the spring, this way you can measure the spacing before and after to ensure you get back the proper tension on the spring. I didnt so it may or may not be necessary.
Good luck and I hope I saved you guys some money.
Oh if at anytime the video gets pulled down, I saved it so I can upload it again.
I tried it 2 weeks ago and it corrected my problem thus far.
A new unit can cost you roughly $4000. Jus be very careful when attempting.
I personally found it a little difficult at two points in the vid and I will try to help you through it.
Heres the vid, unfotunately its not in english but you can see what he does.
Heres what you will need:
A Philips screwdriver
A towel
WD40
Liquid wrench spray (if not try some WD40)
A Birdbeak Pliers
A regular Pliers or Vice Grip
Electrical Contact Cleaner
To remove the ISC on a 4G18 engine look under the throttle body and you will see a black unit, with a 6 wire electrical connector. Unplug the connector and remove the 3 phillip screws that keeps it bolted to the throttle body. Clean out the area in the TB after you removed the unit by spraying some Electrical contact cleaner on a cloth and wiping the insides as far as you could reach.
It seems like he did this alot to this unit. Bet your dollar, your unit wont be as easy to dissemble. Take your time, dont squeeze the brown part too much it will break part.
Also theres an O-ring around the surface of the ISC that bolts to the TB, take it out an keep it safe.
0:00-0:26 He's explaining that the brown part is locked into the unit.
Start by spraying Liquid wrench into the 3 holes he pointed to at 0:08
Use the Birdbeak pliers and place it over the spring in the space between the brown part and black bolt looking piston. The object here is to pull the piston out some more, away from the motor.
So hold on the unit with your left hand, bird beak over the spring, and pull outward, the piston should move a lil bit...that should be enough
0:26-0:30 Problem 1: No you cant turn that with your hand, you will need a pliers or vice grip and a cloth. Please do not squeeze the pliers YOU WILL BREAK THE BROWN PART. Rotate the brown part anti-clockwise like the guy did.
0:30-0:45 You will now see 3 brown notches in the 3 holes you sprayed with liquid wrench.
0:45-0:58 Problem 2: No it will not come out that easily, you will have to wiggle and pull. If you find that its not coming all the way out to unscrew the brown part then you need to do the part with the bird beak pliers again, that will free up space for the brown lock to rotate.
0:58-1:12 The object here is to hold onto the brown part and rotate the entire motor so it will unscrew and detach.
1:12-1:17 Take this time to clean the insides of the brown part, spring and black piston with Electrical cleaner.
1:17-1:38 Do exactly as he did, make sure and use the towel and a pliers or vice grip.
If you not getting it out, spray a little Liquid Wrench.
1:38-1:53 The guy is explaining that the silver ring needs to rotate freely, if you try rotating yours it may feel a little gritty. Spray it with some Electrical contact spray and clean, clean everything with the contact spray, even the rest of the housing. The contact spray will self dry.
When the motor itself is clean and dry, spray some WD40 where the guy sprayed his.
Primarily on outer edge of the silver ring. Make sure its lubricated and spinning freely.
DO NOT spray it in the ISC housing, I left mine clean and dry.
Mounting back up:
2:35-2:40 Replace the motor back into the housing as snug and far as it could go.
2:40-3:05 Re-fit the spring into the brown lock and black piston and screw it back into the motor
Hold onto the brown lock and keep turning as snug as possible until the 3 notches on the brown part lines up with the holes on the ISC housing.
3:16 Push back in the brown housing, then push back in the black piston too.
3:19 rotate the brown lock clockwise for it to lock back in place.
My only recommendation if you want is to use a caliper gauge and measure the gap between the brown lock and black piston by the spring, this way you can measure the spacing before and after to ensure you get back the proper tension on the spring. I didnt so it may or may not be necessary.
Good luck and I hope I saved you guys some money.
Oh if at anytime the video gets pulled down, I saved it so I can upload it again.
