Not sure what to do
12-26-08, 02:57 AM
#1
Exhaustage Leakage
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Not sure what to do
I've got a few issues that may or may not be related and i'm not sure how to go about fixing them. I've got an 87 SE NA with the two most annoying problems currently being that the car will sometimes die a second after cranking it both hot and cold, also died once while idling soon after a hot start at a stoplight, bleh.
I also have a high idle a little over 2k that persists after the car warms up, sometimes drops to 1500 after driving for an extended period. Increasingly rarely over time has dropped to a normal idle of 750 with a hot start (could be the transition from summer to winter now that I think about it). Well actually now it drops to just over 1k since I messed with the idle screwing thinking I could lower the idle that way, that was dumb. Those are the main issues.
There's also the 3800rpm hesitation and the dash lights and throttle drops when I step on the brake.
So far I've followed Aaron's Proper RX-7 Grounding Procedures guide to clean up some of the grounds although I can't get to the ecu one. Actually I think the ecu ground might be missing or maybe moved elsewhere because I can see an empty bolt hole right where it should be based on Aaron's pics. Is the carpet hard to take off the passenger side floor? I'd rather reground the ecu there instead of taking off the UIM.
Thanks a bunch if you read all this!
PS Are the first row of butterflies in the upper part of the throttle body supposed to be open when the car is cold/off?
I also have a high idle a little over 2k that persists after the car warms up, sometimes drops to 1500 after driving for an extended period. Increasingly rarely over time has dropped to a normal idle of 750 with a hot start (could be the transition from summer to winter now that I think about it). Well actually now it drops to just over 1k since I messed with the idle screwing thinking I could lower the idle that way, that was dumb. Those are the main issues.
There's also the 3800rpm hesitation and the dash lights and throttle drops when I step on the brake.
So far I've followed Aaron's Proper RX-7 Grounding Procedures guide to clean up some of the grounds although I can't get to the ecu one. Actually I think the ecu ground might be missing or maybe moved elsewhere because I can see an empty bolt hole right where it should be based on Aaron's pics. Is the carpet hard to take off the passenger side floor? I'd rather reground the ecu there instead of taking off the UIM.
Thanks a bunch if you read all this!
PS Are the first row of butterflies in the upper part of the throttle body supposed to be open when the car is cold/off?
12-26-08, 11:49 AM
#3
HAILERS
Join Date: May 2001
Location: FORT WORTH, TEXAS,USA
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The outer set of secondary throttle plates should be open with the engine off.
If the double throttle diapharm is functional, then they will close when you start the car and the engine is cold. Then as the engine heats up they'll go full open.
They're spring loaded to open when there is no vacuum going to the double throttle diaphram.
Make sure that the water hoses coming and going from the throttle body are in place and not capped off.
Also idle your car fully hot, then pull the plug off the BAC and see if the idle rpm changes. Should if it's functional AND the rpms are under 750rpm.
If both water hose are there, then remove the throttle body. Boil a pot of water. Pour the water over the item in the attached jpg called Water Thermowax. The cam and the roll pin should seperate as the piston on the waterthermowax extends.
See the FSM for how to adjust the item. What happens is, when the engine is cold, the piston retracts into the water thermowax body. The throttle linkage MOVES when that happens and the throttle plates open a bit. That results in a high idle when the engine is started cold. As the engine warms up, the piston extends, Moving the throttle linkage again, but this time towards full closed, lowering the idle speed. See FSM.
If the double throttle diapharm is functional, then they will close when you start the car and the engine is cold. Then as the engine heats up they'll go full open.
They're spring loaded to open when there is no vacuum going to the double throttle diaphram.
Make sure that the water hoses coming and going from the throttle body are in place and not capped off.
Also idle your car fully hot, then pull the plug off the BAC and see if the idle rpm changes. Should if it's functional AND the rpms are under 750rpm.
If both water hose are there, then remove the throttle body. Boil a pot of water. Pour the water over the item in the attached jpg called Water Thermowax. The cam and the roll pin should seperate as the piston on the waterthermowax extends.
See the FSM for how to adjust the item. What happens is, when the engine is cold, the piston retracts into the water thermowax body. The throttle linkage MOVES when that happens and the throttle plates open a bit. That results in a high idle when the engine is started cold. As the engine warms up, the piston extends, Moving the throttle linkage again, but this time towards full closed, lowering the idle speed. See FSM.