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1toyotafolife
02-28-2008, 07:48 PM
Ok first of all I just installed a used jdm motor in at the begining of the month.
Runs fine but it idles a lil under 2k when motor is warm after I have adjusted it the lowest it will go. When I drive for about an 30 min or more around town it starts to choke and then dies. I have to chill for 10 min or so untill it cools down to start it again. The temp gauge reads normal but when I get out to check the top radiator hose it does not have any pressure? I know the vaccume hoses on top of the thermostat housing are broke. So could that be the problem?:1zhelp:

Sl1dewaysSupra
02-28-2008, 08:23 PM
Usualy no pressure in a rad hose is a clog in the system(One would think that the temp would read hot though.) or a bad rad cap. Did you re-use your old cap? Could be heatsoak?

1toyotafolife
02-28-2008, 08:47 PM
Yes I reused my rad cap.

Sl1dewaysSupra
02-28-2008, 09:01 PM
Replacing the cap is the easiest place to start. Does your heater work?

1toyotafolife
02-28-2008, 09:03 PM
yea the heater blowes hot but I had to tie a wire around the valve to close it

AJ'S 88NA
02-28-2008, 09:27 PM
Ok first of all I just installed a used jdm motor in at the begining of the month.
Runs fine but it idles a lil under 2k when motor is warm after I have adjusted it the lowest it will go. When I drive for about an 30 min or more around town it starts to choke and then dies. I have to chill for 10 min or so untill it cools down to start it again. The temp gauge reads normal but when I get out to check the top radiator hose it does not have any pressure? I know the vaccume hoses on top of the thermostat housing are broke. So could that be the problem?:1zhelp:
How did you adjust the idle? There isn't a idle adjustment. You need to fix the vacume hoses first. Any vacume leaks are going to give you idle problems.

1toyotafolife
02-28-2008, 09:57 PM
yea I need a new bvsv mine is broken

1toyotafolife
02-28-2008, 09:58 PM
How did you adjust the idle? There isn't a idle adjustment. You need to fix the vacume hoses first. Any vacume leaks are going to give you idle problems.

Well I thought the screw on the throttle.

AJ'S 88NA
02-28-2008, 11:23 PM
Well I thought the screw on the throttle.
The idle is controlled by the ECU. I don't know what screw you are talking about, there is adjustment nuts on the cable, a throttle stop screw and that's about it.

The BVSV is for the charcoal canister. But if you haven't capped off the vac lines to the throttle body you should cap them off to see if the idle comes down.

jetjock
02-28-2008, 11:55 PM
As AJ pointed out idle is ECU controlled. Assuming the throttle plate is fully closed (verify it is) the only other idle air paths are the PCV system and idle speed control valve.

Try plugging the PCV inlet on the throttle body and pinching off or plugging the idle hose ahead of the valve. The engine should die. If it doesn't you have pirate air somewhere.

Another possibility is since the ISCV steps fully open after shutdown it may have failed in that state. I say that because a fully open valve will result in an idle of a little less than 2K.

AJ'S 88NA
02-29-2008, 10:03 AM
As AJ pointed out idle is ECU controlled. Assuming the throttle plate is fully closed (verify it is) the only other idle air paths are the PCV system and idle speed control valve.

Try plugging the PCV inlet on the throttle body and pinching off or plugging the idle hose ahead of the valve. The engine should die. If it doesn't you have pirate air somewhere.

Another possibility is since the ISCV steps fully open after shutdown it may have failed in that state. I say that because a fully open valve will result in an idle of a little less than 2K.

Damn JJ you ought to stickie all the little tricks you know to check things out, they don't put all those in the TSRM. You have a very common-tech way of looking at things and how they relate and react that even I can understand.:) Glad you are here. I can suggest things that might be the problem, but you give info and simple ways to check operations of the possible problems.:bigthumb: