well after doing some research on my idle problem after my rebuild, i set the tps, i made sure the tps was in good order, and i guess all thats left to troubleshoot is the ISC... is there anythign in particular that i can use to clean it out??? fast responses would be much appreciated.. thanks
tips please (cleaning ISC)
- Thread starter bhgmaster
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The filter under it may be clogged up with carbon as well. You have to remove the ISC from the manifold (2 bolts) and the filter is under it in a recess on the manifold...it looks like a little spoke mag wheel. Don't try and clean it...buy a new one from Toyota.
To clean the ISC itself, remove it from the manifold and take the 3 screws off that hold the black electric valve on the flange. Be careful, the screws are easy to strip the philips head. Take some carb or brake cleaner and clean the spring/valve head...clean the valve seat side too on the flange. I wouldn't use Simple Green on the electric side...good stuff, but wouldn't want it getting inside the electric part. Reassemble by aligning the philips screw holes and tighten down a little at a time by going around all 3.
To clean the ISC itself, remove it from the manifold and take the 3 screws off that hold the black electric valve on the flange. Be careful, the screws are easy to strip the philips head. Take some carb or brake cleaner and clean the spring/valve head...clean the valve seat side too on the flange. I wouldn't use Simple Green on the electric side...good stuff, but wouldn't want it getting inside the electric part. Reassemble by aligning the philips screw holes and tighten down a little at a time by going around all 3.
Agreed, use carb cleaner, and get a new gasket an filter should be like $8 from toyota. I think the gasket is like $2.50 or so.
ISCV failures are sometimes bearing related so cleaning won't always help. Clean more than the pintle and seat. I prefer to power the thing either on or off the car while cleaning the shaft and stopper plate.
The pintle only moves 11 degrees per step and since the ecu allows only a 20 rpm deviation from target idle speed the valve needs to move freely to stay on top of things. Put something like a ty wrap on it and power it to see if you're getting around 11 degrees per step. Or step it 33 times to see if you get one rev.
jdub, the fliter is actually a check valve used to keep boost out of the ISC system but you're right, it should be checked as a failure will result in the same condition as a blown CBV.
The pintle only moves 11 degrees per step and since the ecu allows only a 20 rpm deviation from target idle speed the valve needs to move freely to stay on top of things. Put something like a ty wrap on it and power it to see if you're getting around 11 degrees per step. Or step it 33 times to see if you get one rev.
jdub, the fliter is actually a check valve used to keep boost out of the ISC system but you're right, it should be checked as a failure will result in the same condition as a blown CBV.
You can take ISCV to Autozone and they'll test it for you for free. That's what I did before I cleaned mine to make sure it was in perfect working order.
jetjock said:
I didn't realize that...thanks! I've taken a bunch of these apart to chrome the aluminum base/flange. Always thought that was a filter :icon_conf
Sure, no problem. Next time you have one out look at it and you'll see it's designed to flow only in one direction. After all, when you pump up the intake plenum you don't want that pressure going back into the ICS system. More than one boost "leak" has been caused by that guy and since it's hidden it's hard to find without a pressure test. They also tend to fall out when the ISCV is removed and go missing. I've repaired two turbo cars where it simply wasn't there.