Sputtering, stalling, lean conditions
05-14-2007, 03:06 PM
#91
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Originally Posted by drivefast617,May 14 2007, 03:49 PM
Just another angle on this problem.......
if it's hot outside when your idleing or going slow - it's possible your IAT is heat soaking from your engine and maybe 170+ degrees F. If this is the case, you get idle problems and timing is changed,dropped HP,etc.
If it's not hot outside, maybe this isn't your issue.
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maybe to test -- get some (intake air temp) IAT OBD2 reading while it's happening. see what degrees the IAT sensor is when it's happening. (also compare difference between water temp and IAT as in our car they get too close unfortantely).
and if you don't have obd2, maybe do this.. -- get car hot by idleing on hot day. reproduce the problem on idle with hood closed.
Once you reproduce - open hood, pour a cold bottle of water on the IAT (the top of the manifold where the sensor is). if you do have obd2, temp should drop 20-50degrees. See if the idle probelmgoes away.
if it does, go away, then I think you have a HEAT soak issue. the solution for that varies.
P.S. I'm going to the SCCA National Tour in Houston this weekend and hope to win Astock like I did last year in Cstock. When i return, I'll be reporting some very interesting information on "how to avoid HEAT soak for autox" in the autox section.
if it's hot outside when your idleing or going slow - it's possible your IAT is heat soaking from your engine and maybe 170+ degrees F. If this is the case, you get idle problems and timing is changed,dropped HP,etc.
If it's not hot outside, maybe this isn't your issue.
======
maybe to test -- get some (intake air temp) IAT OBD2 reading while it's happening. see what degrees the IAT sensor is when it's happening. (also compare difference between water temp and IAT as in our car they get too close unfortantely).
and if you don't have obd2, maybe do this.. -- get car hot by idleing on hot day. reproduce the problem on idle with hood closed.
Once you reproduce - open hood, pour a cold bottle of water on the IAT (the top of the manifold where the sensor is). if you do have obd2, temp should drop 20-50degrees. See if the idle probelmgoes away.
if it does, go away, then I think you have a HEAT soak issue. the solution for that varies.
P.S. I'm going to the SCCA National Tour in Houston this weekend and hope to win Astock like I did last year in Cstock. When i return, I'll be reporting some very interesting information on "how to avoid HEAT soak for autox" in the autox section.
05-14-2007, 08:22 PM
#92
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Inlet Air Temperature sensor, Manifold Absolute Pressure sensor, not the same. Its definitely not heat soak, I have hondata IMG and it was doing this months ago during 50 degree weather. My problem is 95% solved but I still get a weird idle surge sometimes. I'm leaving it for hoping it will get bad enough to easily diagnose or at least become more consistent.
05-14-2007, 08:36 PM
#93
Originally Posted by S|2ocK,May 14 2007, 08:22 PM
Inlet Air Temperature sensor, Manifold Absolute Pressure sensor, not the same. Its definitely not heat soak, I have hondata IMG and it was doing this months ago during 50 degree weather. My problem is 95% solved but I still get a weird idle surge sometimes. I'm leaving it for hoping it will get bad enough to easily diagnose or at least become more consistent.
Replaced - MAP, Sparkplugs, O2 Sensor
Tried - ECU, Injectors, Coils
Adjusted - valves
Only thing I still plan on doing is inspecting my CATCON to make sure it is not clogged in any way. Other than that - waiting for a CEL and code
05-14-2007, 10:47 PM
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Replaced my IAC and reset the ECU. Ran good for one full day. Then the next day on my way to class it started acting up again. Gonna swap ECU's tomorrow. Im sorry but I dont see how "heat soak" can be the problem. This "hesitation" problem happens on completly stock s2k's as well. There is no way in hell the car could be sold by a dealer with this as a potential issue to deal with. lol Like some old ass woman is gonna put up with bucking/surging from a new car... Know what I mean? I too autocross and from my understanding:
Hot air going into hot engine = lower performance, not surging/bucking......
The colder the air the more dense it is. Hence more dense mixture = more hp.
I know heat soak exists but not when my car is back completly stock now, like it came from the factory, and it still fawks up!!!
Haha Hey Will, you ever get the number for that Voodoo Doctor???
I might need him.
Hot air going into hot engine = lower performance, not surging/bucking......
The colder the air the more dense it is. Hence more dense mixture = more hp.
I know heat soak exists but not when my car is back completly stock now, like it came from the factory, and it still fawks up!!!
Haha Hey Will, you ever get the number for that Voodoo Doctor???
I might need him.
05-15-2007, 05:22 AM
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I see.. looks like HEAT soak isn't S|2ocK's problem.
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millertown - i won't debate heatsoak with you on this thread as the subject will change. But look for me in the autox/race forums for some hard data with gps/obd2 with excel and graphs. I know what you mean about density of air.. and the tests prove that the air is in fact cooler than the IAT thinks it is.
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Ok.. just wanted to mention for all you guys in the south with 100 degree weather.
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millertown - i won't debate heatsoak with you on this thread as the subject will change. But look for me in the autox/race forums for some hard data with gps/obd2 with excel and graphs. I know what you mean about density of air.. and the tests prove that the air is in fact cooler than the IAT thinks it is.
====
Ok.. just wanted to mention for all you guys in the south with 100 degree weather.
05-15-2007, 03:47 PM
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sure, for those now or in the future considering HEAT soak -- i just posted this a few minutes ago..
https://www.s2ki.com/forums/index.ph...&f=11&t=489973
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others - keep up the trouble shooting so when it happens to me i have info
thanks.
https://www.s2ki.com/forums/index.ph...&f=11&t=489973
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others - keep up the trouble shooting so when it happens to me i have info
thanks.
05-15-2007, 06:28 PM
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Originally Posted by WLAURENT,May 14 2007, 08:36 PM
My problems seem to be gone for the most part - not sure if any one thing I did helped or if it was a combination of two or more:
Replaced - MAP, Sparkplugs, O2 Sensor
Tried - ECU, Injectors, Coils
Adjusted - valves
Only thing I still plan on doing is inspecting my CATCON to make sure it is not clogged in any way. Other than that - waiting for a CEL and code
Replaced - MAP, Sparkplugs, O2 Sensor
Tried - ECU, Injectors, Coils
Adjusted - valves
Only thing I still plan on doing is inspecting my CATCON to make sure it is not clogged in any way. Other than that - waiting for a CEL and code
. My car seems to run really good, theres just that once in a while when it feels like screwing with me. What is the CATCON? I still want to do the EVAP check but I dont think theres a problem there.
05-15-2007, 06:49 PM
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Originally Posted by WLAURENT,May 15 2007, 07:44 PM
CATCON = Catalytic Converter
Have heard of a few getting clogged up with carbon deposits. A little extra back-pressure could cause strange issues.
Have heard of a few getting clogged up with carbon deposits. A little extra back-pressure could cause strange issues.