10.0 and 18.9 idle drops, Im rdy to blow this thing up!! Need some help
Jul 23, 2008, 09:23 AM
#16
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not a whole lot of help here....but when I was in Idaho (5500' asl) my boost gauge NEVER showed more than 15" at idle, and would only hit 17" or so on decel. Now that I am in Maine (sea level), it sits on 17" and hits 23" or so on decel.
Just wanted to throw that out there for people using that symptom to diagnose his problem. From what Ive seen with my car, its normal. Want to really scare yourself? Do compression check at high altitude... I gained 35-40 lbs just by relocating to sea level.
Just wanted to throw that out there for people using that symptom to diagnose his problem. From what Ive seen with my car, its normal. Want to really scare yourself? Do compression check at high altitude... I gained 35-40 lbs just by relocating to sea level.
Jul 23, 2008, 10:55 AM
#17
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do a boost leak check, pay attention to your throttle body shaft seals. These leak frequently, and I would recommend changing them when you clean the ISV.
Does the idle still rise when you turn on the AC? if not, then the ISV might be faulty and need replacement.
Does the idle still rise when you turn on the AC? if not, then the ISV might be faulty and need replacement.
Jul 23, 2008, 11:40 AM
#18
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The idle does still rise when the AC is on sits about at 13 but every few seconds will go to 10 or 11. I sat in the car for about 30 mins today just playing with stuff to see what happens to the idle. With nothing on the car idle at or about 15. Turn the AC on it jumps to 10 or 11 then comes to down to 13 for about 10 seconds the creeps back to 10.
The elevation as Charlie said is something I think is having a big effect on the problem as it was tuned at sea level although I do hit 20 vacuum on decel. I am going to double check everything again when I get off work and reset the ECU by disconnecting the battery and see how that goes. If not its back to the drawing board with a boost leak test and hopefully something shows up.
The elevation as Charlie said is something I think is having a big effect on the problem as it was tuned at sea level although I do hit 20 vacuum on decel. I am going to double check everything again when I get off work and reset the ECU by disconnecting the battery and see how that goes. If not its back to the drawing board with a boost leak test and hopefully something shows up.
Jul 23, 2008, 05:09 PM
#21
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Oka after resetting the battery still no love. Although I did notice that when I turn the AC the RPMs do not increase at all, they actually fall about 50 for a second then recover. Could this be the cause? Also interestingly enough my walbro started to whine again, which I have not heard since the problem began it used to whine all the time and now just stated again. Maybe its gettings better but would the AC indicate a bad ICV and could that cause the idle drop when i come to a stop?
Jul 23, 2008, 07:44 PM
#22
It could be the ICV itself or the ISCV table in the ROM ... the ECU first references the ISCV value that fits the variables (AC on, moving, stopped) and then makes adjustments to reach the desired idle RPM. So, if the ISCV values for "Condition: AC ON" (Desired ISCV with AC on) were too low the idle would drop for a moment when the AC was turned on.
Jul 23, 2008, 10:10 PM
#25
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The plugs have not been changed as far as I know, currently at 25k miles. Maybe its time for a change.
Jul 24, 2008, 07:48 AM
#26
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Actually my car would misfire like crazy. I removed my step 1 colder plugs and I found out that the gap had opened from 0.024 to 0.028. I replaced them with a new set of OEM plugs and now I am waiting for Saturday when I will install a brand new set of properly gapped step 1 colder...
I will let you know how it will go...
I will let you know how it will go...
Jul 24, 2008, 10:05 AM
#27
Have you ever taken off the throttle cable. The reason I ask is because where the throttle cable is bracketed behind the Valve Cover its has 2 bolts on a slide bracket
It needs to be adjusted too tight it'll idle high and leave the plate open on decel. Too loose and you would have the issues you are describing
It needs to be adjusted too tight it'll idle high and leave the plate open on decel. Too loose and you would have the issues you are describing
Jul 25, 2008, 04:41 PM
#30
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Mine idles around 23-25" vac and >30" solid when decelerating. Ive done a boost leak check with a endcap on the turbo and a bicycle tire pump. LOL, it blew off at ~17psi and sounded like shotgun going off in my driveway. Your low vacuum sounds like a leak, high altitudes should not have that serious of an impact, I agree with a boost/vac leak check.