My Nightmare...
cant believe you would let this go on for this long without having it looked at by someone other than ams, sure they are ams..... I have been to ams and also bushur in the past, and I was lucky enough to meet Devin Schultz bout six years ago, and since my car has been on the road, running like a top. I had an issue similar to yours, but I'm on an aem v1, was a long time ago cant remember exactly what it was but one quick trip to BP performance and you'll be good to go. I daily mine 95 miles round trip EVERYDAY, Devins tune put bushurs to shame.. wish I met him a little sooner, would a saved me a lot of gas money driving to ohio and dealing with ams. do yourself a favor, and get the fun and hassle free driving back, and bring it in to Devin you will not be sorry. looks like a fun set-up good luck getting the bugs worked out and I don't think its anything to do with injectors but boostin has injector machine also just to rule out.
sorry for long read, I'm just a lurker g\l
sorry for long read, I'm just a lurker g\l
I assume you are running a MIVEC head?
How is your oil pressure?
Based on the troubleshooting you have done on the fuel system and intake and exhaust sensors, I'm wondering if you are having a cam issue. It sounds like the car is having some really bad combustion at idle, then the control system slams the control valve open and/or adjust fuel to compensate. Couple scenarios I could envision:
1. Cam position sensors bad or going bad. Not likely, since it doesn’t seem you have any fault codes (Or do you?)
2. Cam position rings not installed correctly, maybe they are clocked incorrectly, or installed on the wrong cam. Don’t have enough wrench time on the MIVEC head to know if this scenario is even possible, just throwing it out there.
4. MIVEC valve malfunctioning. Wondering if the valve is stuck or working poorly, causing bad response.
3. Final scenario, and reason why I asked about oil pressure. Wondering if the MIVEC system isn’t getting enough oil to properly move the cam into position at low speed. Obviously, you don’t have many issues at high speed, since oil pressure would be able to move the cam properly. Obviously this has major implications on the health of your engine, so hopefully it is not the case. If you have aftermarket valve springs, it is even more important for the MIVEC system to get sufficient oil, since the cams see more resistance from the springs.
Edit: Anyone know if MIVEC equipped cars detect faults for cam position tracking error? I.e. steady state difference between commanded position and actual position.
How is your oil pressure?
Based on the troubleshooting you have done on the fuel system and intake and exhaust sensors, I'm wondering if you are having a cam issue. It sounds like the car is having some really bad combustion at idle, then the control system slams the control valve open and/or adjust fuel to compensate. Couple scenarios I could envision:
1. Cam position sensors bad or going bad. Not likely, since it doesn’t seem you have any fault codes (Or do you?)
2. Cam position rings not installed correctly, maybe they are clocked incorrectly, or installed on the wrong cam. Don’t have enough wrench time on the MIVEC head to know if this scenario is even possible, just throwing it out there.
4. MIVEC valve malfunctioning. Wondering if the valve is stuck or working poorly, causing bad response.
3. Final scenario, and reason why I asked about oil pressure. Wondering if the MIVEC system isn’t getting enough oil to properly move the cam into position at low speed. Obviously, you don’t have many issues at high speed, since oil pressure would be able to move the cam properly. Obviously this has major implications on the health of your engine, so hopefully it is not the case. If you have aftermarket valve springs, it is even more important for the MIVEC system to get sufficient oil, since the cams see more resistance from the springs.
Edit: Anyone know if MIVEC equipped cars detect faults for cam position tracking error? I.e. steady state difference between commanded position and actual position.
Last edited by Mercenary3; Feb 16, 2014 at 09:10 PM.
The hanging rich condition could be caused by an improperly adjusted tps. It doesn't see the correct voltage to know to cut fuel on decel. The idle may straighten itself out after the tps is adjusted properly. If it doesn't it seems like a straight forward case of bad ISC or an improperly set BISS. The base idle on a lightweight rotating assembly like that should be a little higher because it will decel a lot quicker. For it to catch with the ISC is very difficult. Adjust the BISS out a turn or so and set the idle with the ISC disconnected to about 1300. Then the ISC will be used to lower the rpm instead of trying to raise it from 500 before it stalls.
The hanging rich condition could be caused by an improperly adjusted tps. It doesn't see the correct voltage to know to cut fuel on decel. The idle may straighten itself out after the tps is adjusted properly. If it doesn't it seems like a straight forward case of bad ISC or an improperly set BISS. The base idle on a lightweight rotating assembly like that should be a little higher because it will decel a lot quicker. For it to catch with the ISC is very difficult. Adjust the BISS out a turn or so and set the idle with the ISC disconnected to about 1300. Then the ISC will be used to lower the rpm instead of trying to raise it from 500 before it stalls.
I assume you are running a MIVEC head?
How is your oil pressure?
Based on the troubleshooting you have done on the fuel system and intake and exhaust sensors, I'm wondering if you are having a cam issue. It sounds like the car is having some really bad combustion at idle, then the control system slams the control valve open and/or adjust fuel to compensate. Couple scenarios I could envision:
1. Cam position sensors bad or going bad. Not likely, since it doesn’t seem you have any fault codes (Or do you?)
2. Cam position rings not installed correctly, maybe they are clocked incorrectly, or installed on the wrong cam. Don’t have enough wrench time on the MIVEC head to know if this scenario is even possible, just throwing it out there.
4. MIVEC valve malfunctioning. Wondering if the valve is stuck or working poorly, causing bad response.
3. Final scenario, and reason why I asked about oil pressure. Wondering if the MIVEC system isn’t getting enough oil to properly move the cam into position at low speed. Obviously, you don’t have many issues at high speed, since oil pressure would be able to move the cam properly. Obviously this has major implications on the health of your engine, so hopefully it is not the case. If you have aftermarket valve springs, it is even more important for the MIVEC system to get sufficient oil, since the cams see more resistance from the springs.
Edit: Anyone know if MIVEC equipped cars detect faults for cam position tracking error? I.e. steady state difference between commanded position and actual position.
How is your oil pressure?
Based on the troubleshooting you have done on the fuel system and intake and exhaust sensors, I'm wondering if you are having a cam issue. It sounds like the car is having some really bad combustion at idle, then the control system slams the control valve open and/or adjust fuel to compensate. Couple scenarios I could envision:
1. Cam position sensors bad or going bad. Not likely, since it doesn’t seem you have any fault codes (Or do you?)
2. Cam position rings not installed correctly, maybe they are clocked incorrectly, or installed on the wrong cam. Don’t have enough wrench time on the MIVEC head to know if this scenario is even possible, just throwing it out there.
4. MIVEC valve malfunctioning. Wondering if the valve is stuck or working poorly, causing bad response.
3. Final scenario, and reason why I asked about oil pressure. Wondering if the MIVEC system isn’t getting enough oil to properly move the cam into position at low speed. Obviously, you don’t have many issues at high speed, since oil pressure would be able to move the cam properly. Obviously this has major implications on the health of your engine, so hopefully it is not the case. If you have aftermarket valve springs, it is even more important for the MIVEC system to get sufficient oil, since the cams see more resistance from the springs.
Edit: Anyone know if MIVEC equipped cars detect faults for cam position tracking error? I.e. steady state difference between commanded position and actual position.
just being honest. But now I'm thinking it's definitely a possibility. The thing that blows my mind however is the motor ran beautifully until the build was done... I put a brand new oil plate/pump in as well. Give it a few days to warm up out here and I'll check what I can. Location of the mivec valve is where exactly?Also, I just want to say thank you to everyone responding to my thread I really appreciate all the help and it is making me feel a lot more confident that I'll figure this out.
Evolved Member
iTrader: (33)
Joined: Jul 2002
Posts: 5,313
Likes: 1
From: Raleigh, Transplanted from Toronto, Canada
Rear O2 voltage low? Never heard of that one. Is it disabled in the ECU? Electrical issues relating to the wireharness? I know its easy to say that and its a bear to trouble shoot but you could very well have an issue with that. If you know someone with a spare stock ECU I would try flashing your map on that and see if you have the same issue as well.
Local had some weird issues similar to what you are experiencing and Spec-Ops troubleshot that thing for a while and then decided to try another stock ECU......problem cleared right up.
Local had some weird issues similar to what you are experiencing and Spec-Ops troubleshot that thing for a while and then decided to try another stock ECU......problem cleared right up.
dont know if this is much i help. but i had the EXACT same problem ( except i had power in first).
a week later i went speed density and got a dyno tune and it disappeared, but in the mean time i also changed my intake manifold and TB...=/
do you have a leak in your TB shaft seals, because my car didnt decel ether when mine where leaking?
also you should cap you IM lines instead of looping them.
check if you IAC is clean and not broken
a week later i went speed density and got a dyno tune and it disappeared, but in the mean time i also changed my intake manifold and TB...=/
do you have a leak in your TB shaft seals, because my car didnt decel ether when mine where leaking?
also you should cap you IM lines instead of looping them.
check if you IAC is clean and not broken
dont know if this is much i help. but i had the EXACT same problem ( except i had power in first).
a week later i went speed density and got a dyno tune and it disappeared, but in the mean time i also changed my intake manifold and TB...=/
do you have a leak in your TB shaft seals, because my car didnt decel ether when mine where leaking?
also you should cap you IM lines instead of looping them.
check if you IAC is clean and not broken
a week later i went speed density and got a dyno tune and it disappeared, but in the mean time i also changed my intake manifold and TB...=/
do you have a leak in your TB shaft seals, because my car didnt decel ether when mine where leaking?
also you should cap you IM lines instead of looping them.
check if you IAC is clean and not broken
Rear O2 voltage low? Never heard of that one. Is it disabled in the ECU? Electrical issues relating to the wireharness? I know its easy to say that and its a bear to trouble shoot but you could very well have an issue with that. If you know someone with a spare stock ECU I would try flashing your map on that and see if you have the same issue as well.
Local had some weird issues similar to what you are experiencing and Spec-Ops troubleshot that thing for a while and then decided to try another stock ECU......problem cleared right up.
Local had some weird issues similar to what you are experiencing and Spec-Ops troubleshot that thing for a while and then decided to try another stock ECU......problem cleared right up.
Evolved Member
Joined: Mar 2008
Posts: 2,110
Likes: 320
From: Croatia
Evolved Member
Joined: Mar 2008
Posts: 2,110
Likes: 320
From: Croatia
actually, it is real easy to check if it is a maf issue... just unplug the maf and see if the idle will stabilise... ofc, your throttle sensor needs to be adjusted correctly..
also, log the maf freq at idle.. if it jumps around a lot it is a maf problem and you should switch to SD..
Close that DV and see if it gets better..
also, log the maf freq at idle.. if it jumps around a lot it is a maf problem and you should switch to SD..
Close that DV and see if it gets better..