Got P1128/P1130 at idle.
Hey guys, I got a P1128/P1130 codes at idle. My car runs great. At idle, it vibrates a little bit, but not very obvious. Here is the freezing frame.
FUELSYS1 CL FUELSYS2 CL LOAD_PCT 3.9% ETC 201F SHRIFT1 4.7 LONGFT1 0.8 SHRIFT2 4.7 LONGFT2 -0.8 RPM 680 VSS(mph) 0 I had two freezing frame of P1128. They all happens at 680 RPM and 0 mph. What could be the problem? I assume it is MAF, O2 sensor or vacuum leak. But could I locate it more precisely? Thanks! |
+1 for the vacuum leak or leaks.
|
Quote:
|
Quote:
Not likely to be a problem with the O2 sensors on both banks at the same time. MAF sensor? possibly but I don't see anything unusual in your freeze frame data. So Go with the old automotive diagnostic adage of simplest things first. Which would be a proper vacuum test. a vacuum test gauge cost about 15-20 bucks. A proper vacuum test will tell you if you have a vacuum leak or not. The reason your car idles a little rough then smooths out and runs fine above idle is: As you open the throttle and give the engine more and more air the unmetered air "vacuum leak" becomes less and less a part or percentage of the total air taken in by the engine. So lets say at idle (throttle closed) your vacuum leak is allowing 10 percent more air into the engine at idle then it needs. Your DME OR ECU doesn't see it because the leak is after the MAF sensor. But as you open the throttle to lets say half throttle now you vacuum leak is down to say 3 percent of the air that the DME or ECU doesn't see. So now the air intake is closer to correct for the engine load so it smooths out and runs better. Hope that makes sense:D as I am not very good at explaining things. I am reasonable sure you have a vacuum leak based on the info you provided. But I could still be wrong: hard to be certain when I don't have the car before me. |
Quote:
This is why you can erase some codes and they take some time to reappear. If you were having an issue that was immediately harmful to the catalytic converter the OBDII system would trigger your check engine light on the first event. A misfire is an example of such an issue. |
Quote:
|
Quote:
I never take my cars to someone else.;) If you take it to a shop most are parts changers these days. Try to find one that has a person with true diagnostic abilities. More and more rare these days and hard to find. |
AOS is suspect.
At idle remove your oil fill cap... Is it difficult to remove? After removal does the opening sound like a Shop Vac? Put your hand over the opening... Is there a lot of suction? |
Quote:
I can hear the leak is around the AOS. I may do a smoke test. Thanks! |
Quote:
Mine (same codes - car ran fine) was unseated hose from TB to AOS creating vacuum leak |
Quote:
|
Quote:
. |
Quote:
|
Quote:
When I replaced the AOS on my 987CS I had to buy the accordion hose as I damaged mine.. . |
Quote:
We are not prejudice of our 987 Brothers... All are welcome here on this site. :):dance: |
Quote:
|
Quote:
|
Quote:
Link? Proof? Thanks. |
Quote:
|
Quote:
The diaphragm inside the AOS is cracked. |
All times are GMT -8. The time now is 02:29 AM. |
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website