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Discussion Starter · #1 ·
At times, while driving and have to come to a stop and truck take out of gear, in to neutral. The RPM's drop to 0 and truck stalls. Not always does this happen but happens often enough. Have done tune up, EGR, fuel filter. What module maintains correct RPM's . I have A/C on when this happen.
Thanks
 

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mine does this too sometimes, I dont know what it is either but it doesnt happen all the time. When my truck is cold and I have the ac on it idles like **** up and down until it gets warm. Man it robs power havin the ac too.
 

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My 92 did this randomly... Sprayed the entire intake system with carb cleaner (o2 sensor safe) looking to find a cracked hose... None. Finally found the issue, pcv valve split in half! Check the pcv valve & seal, and oil fill cap (if it's got a bad seal pcv will allow too much air into the int manifold).

~psguardian
 

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psguardian said:
My 92 did this randomly... Sprayed the entire intake system with carb cleaner (o2 sensor safe) looking to find a cracked hose... None. Finally found the issue, pcv valve split in half! Check the pcv valve & seal, and oil fill cap (if it's got a bad seal pcv will allow too much air into the int manifold).

~psguardian
Could that cause it to idle high in Park or Neutral?
 

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Vacuum leaks are funny critters, depending on 15 or 20 uncontrollable variables, they can cause ; high idle, low idle, stallng at idle, lean conditions, etc... I would gently pull on the hose & see if it's still attached, or snapped & being held in by engine grime.

~psguardian
 

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psguardian said:
Vacuum leaks are funny critters, depending on 15 or 20 uncontrollable variables, they can cause ; high idle, low idle, stallng at idle, lean conditions, etc... I would gently pull on the hose & see if it's still attached, or snapped & being held in by engine grime.

~psguardian
I just did Intake Manifold Gaskets on my Rodeo, and it fixed my HIGH idle, but it still idles around 1500 rpms in Park or Neutral. I adjusted the bolts for the manifold slightly today, and checked my vacuum hoses. all were attached so I'm hoping she idles good tomorrow when I go to work
 

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Discussion Starter · #7 ·
Most of the vacuum line have been replaced as well as PCV, manifold and head gasket. Will check PCV and hoses for leaks. Is there a module that controls rpms located inside truck under console?
 

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tufftrooper said:
Most of the vacuum line have been replaced as well as PCV, manifold and head gasket. Will check PCV and hoses for leaks. Is there a module that controls rpms located inside truck under console?
From what I've heard the ECM controls everything in the fuel injected Zu's.

Your IAC valve sort of controls the idle, but its more like you either idle or you don't; I don't really think there's an in between if the IAC fails.
 

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Discussion Starter · #9 ·
TKEPA251 said:
tufftrooper said:
Most of the vacuum line have been replaced as well as PCV, manifold and head gasket. Will check PCV and hoses for leaks. Is there a module that controls rpms located inside truck under console?
From what I've heard the ECM controls everything in the fuel injected Zu's.

Your IAC valve sort of controls the idle, but its more like you either idle or you don't; I don't really think there's an in between if the IAC fails.
Any idea where a good inexpensive after market, high performance ECM control can be purchased?
 

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Only place I can point you is to JET. Find Crash on here and ask him about his JET ECU.

In this thread we found a "universal chip" for all cars, and kinda tore it apart. Crash drops in at the end and talks about JET.
http://forum.planetisuzoo.com/viewtopic.php?t=53120

Other than that you can buy a piggy-back, or stand alone ECU that you can adjust and program to your specs.
 

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Discussion Starter · #11 ·
TKEPA251 said:
Only place I can point you is to JET. Find Crash on here and ask him about his JET ECU.

In this thread we found a "universal chip" for all cars, and kinda tore it apart. Crash drops in at the end and talks about JET.
http://forum.planetisuzoo.com/viewtopic.php?t=53120

Other than that you can buy a piggy-back, or stand alone ECU that you can adjust and program to your specs.
Thanks man, I will check out the thread.
 

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Browse around and see if you find what you're lookin for. He's not super specific in that thread, but it gives you an idea of what he's getting out of his modded ECU.

No problem bud, glad to help.
 

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Discussion Starter · #13 ·
Could the throttle body, be the cause?
 

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tufftrooper said:
Could the throttle body, be the cause?
I doubt it, unless its got a vacuum leak. Does the truck have any check engine lights?

If you want you could PM Jerry (JLEMOND) and ask him. Jerry knows Isuzu's like the back of his hand.

-Robert
 

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There is a fast idle solenoid on the passenger side inner fender that controls the rpm's when the A/C is on. They are about 80 bucks or so.
 

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Discussion Starter · #16 ·
No vacuum leaks and no check engine light on. I would like to try that fast idle solenoid. Where could I find a new one? Thanks guys for the info.
 

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Most auto parts stores can get them, or you can try autopatswharehouse.com or P/M Jerry lemond here on the planet he has the OEM stuff for a very reasonable price.
 
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