Bouncing Idle... doesn't do it with A/C turned on.. A/F mix changes.. lowered boost
06-04-07, 02:55 PM
#1
Bouncing Idle... doesn't do it with A/C turned on.. A/F mix changes.. lowered boost
So I posted a while back some of the issues my car was having...
anyways I still can't find any resolution but before I started getting it up in the air..
Long story short...
All of these conditions are in park (automatic tranny!)
One day the car just decided to give me some horrible bouncing idle.. like 300's up to 750 ish and back and forth.. felt like it was going to die.
Vacuum remained around neg 13
I noticed the Air/Fuel mixture gauge said running rich (even being at operating temp)
Alright.. that was like two weeks ago.. today I paid attention and the following
happened when In park...
When I turned the Air Conditioning on (mine is all hooked up and charged) the thing idled slightly higher but held its idle... the Air fuel ratio went back into the yellow just before the "rich" marking on the gauge (Autometer A/F mixture gauge).
Turning it off while in park causes makes the engine work less hard but sends it back into its bouncing idle loop... one other thing when I turned off A/C was it runs "Rich" on the gauge.
I also noticed that this time I didn't hardly get into the turbos.. kept it mostly below 40mph and the idle problem did not appear till later... so I'm assuming that is because it only happens at operating temperature.. (that is the only time i see it... operating temp at idle.)
I don't know how much more detailed I can get but the only mods on this engine are
downpipe, silicon hoses, Apexi dual intakes... RB muffler
If anyone wants me to provide more information/media/pictures.. whatever.. I will.. but I just want to get a good idea of what I'm going after before I go to work on it.
It also seems that the boost is highly restricted.. I tried my boost patterns and noticed that the first turbo was only boosting like 4psi max and the second was only like 7 or 8 ... I can check this out when I get on it next...
anyways I still can't find any resolution but before I started getting it up in the air..
Long story short...
All of these conditions are in park (automatic tranny!)
One day the car just decided to give me some horrible bouncing idle.. like 300's up to 750 ish and back and forth.. felt like it was going to die.
Vacuum remained around neg 13
I noticed the Air/Fuel mixture gauge said running rich (even being at operating temp)
Alright.. that was like two weeks ago.. today I paid attention and the following
happened when In park...
When I turned the Air Conditioning on (mine is all hooked up and charged) the thing idled slightly higher but held its idle... the Air fuel ratio went back into the yellow just before the "rich" marking on the gauge (Autometer A/F mixture gauge).
Turning it off while in park causes makes the engine work less hard but sends it back into its bouncing idle loop... one other thing when I turned off A/C was it runs "Rich" on the gauge.
I also noticed that this time I didn't hardly get into the turbos.. kept it mostly below 40mph and the idle problem did not appear till later... so I'm assuming that is because it only happens at operating temperature.. (that is the only time i see it... operating temp at idle.)
I don't know how much more detailed I can get but the only mods on this engine are
downpipe, silicon hoses, Apexi dual intakes... RB muffler
If anyone wants me to provide more information/media/pictures.. whatever.. I will.. but I just want to get a good idea of what I'm going after before I go to work on it.
It also seems that the boost is highly restricted.. I tried my boost patterns and noticed that the first turbo was only boosting like 4psi max and the second was only like 7 or 8 ... I can check this out when I get on it next...
I'd especially suspect a vac leak with vacuum as low as 13 in/Hg. Good luck man!
.. gonna become a rotary tech soon ... oh FD woes.. someone should write a song
06-04-07, 07:07 PM
#4
Update
Alright, I took it out on the road today.. after letting it warm up by idling to operating temp..
so water temp never EVER gets hotter than 210 and its rare if it hits that.
Second thing... did 0 - 85mph or so and I noticed that the boost pattern is so awful.... looked like no higher than 6psi on the first turbo and no higher than 4psi on the second.. but i do know for a fact it didn't push any further than 6psi while WOT'n to 85...
Also i noticed something ... when the car was sitting idle at the stop light after the 85mph cruise that it bounced between 750 and 250... no higher no lower...
The A/F was bouncing between the middle of stoich to rich in sync to the idle going up and down..
This is all I could gather and I'm losing my mind if anyone could bail me out!
so water temp never EVER gets hotter than 210 and its rare if it hits that.
Second thing... did 0 - 85mph or so and I noticed that the boost pattern is so awful.... looked like no higher than 6psi on the first turbo and no higher than 4psi on the second.. but i do know for a fact it didn't push any further than 6psi while WOT'n to 85...
Also i noticed something ... when the car was sitting idle at the stop light after the 85mph cruise that it bounced between 750 and 250... no higher no lower...
The A/F was bouncing between the middle of stoich to rich in sync to the idle going up and down..
This is all I could gather and I'm losing my mind if anyone could bail me out!
06-12-07, 06:08 PM
#5
Continuing problem
So it was a warm day in Indy today.. but I had a hard time keeping the car below 190F it was getting around 210-215 and i kept throwing the heat on .. but it never went past it and i didnt drive it hard.
It seems to run like absolute **** when it heats up but acts fairly normal around 180F
still not sure where to look.
Oh yeah my boost is definately off... no more than 6psi on either turbo
again its an automatic..
if anyone can chime it that would be cool.
thanks,
Pauli
It seems to run like absolute **** when it heats up but acts fairly normal around 180F
still not sure where to look.
Oh yeah my boost is definately off... no more than 6psi on either turbo
again its an automatic..
if anyone can chime it that would be cool.
thanks,
Pauli
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06-13-07, 04:19 PM
#8
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I agree, sounds like a vacuum problem... do you know the brake cleaner spray trick? with the car at normal operating temp and at idle spray anything that might lead to your intake somewhere, vacuum lines, connectors anything... and if you hit a spot where the idle changes hit it again until you isolate where it's coming from..
with the up and down rev if your idle is set to low the ecu will compensate for it and raise the idle cause it to bounce. Not sure if the FD does this, but my idle was doing it for a while as well but it stopped after I had done a ton of work.
With the a/c your computer changes your A/F ratio so to compensate for the drag from the pump and what not... that usually smooths the idle out as well as increase your idle RPM.
I would say with the random boost patterns though I would agree with the vacuum thing. also check to make sure that you have all your coolant in the system and that it's not REALLY REALLY REALLY REALLY old.... it being low and not keeping the heat down will affect a lot... your Idle air control (or what ever it's called on the FD) can cause a ton of problems if it's not getting coolant or gummy coolant...
with the up and down rev if your idle is set to low the ecu will compensate for it and raise the idle cause it to bounce. Not sure if the FD does this, but my idle was doing it for a while as well but it stopped after I had done a ton of work.
With the a/c your computer changes your A/F ratio so to compensate for the drag from the pump and what not... that usually smooths the idle out as well as increase your idle RPM.
I would say with the random boost patterns though I would agree with the vacuum thing. also check to make sure that you have all your coolant in the system and that it's not REALLY REALLY REALLY REALLY old.... it being low and not keeping the heat down will affect a lot... your Idle air control (or what ever it's called on the FD) can cause a ton of problems if it's not getting coolant or gummy coolant...
06-14-07, 02:58 AM
#10
Coolant is pretty fresh.. like less than 5k miles.. and the silicon hoses redo job is about 10k miles old.. something may have slipped off.. but I really appreciate the time you fellas have taken into looking at my problem. I will hold up my end and go test it, let you guys know one way or the other
06-15-07, 12:55 AM
#11
may have found it
Update 2am fri the 15th
well this is the first time ive ever got down and dirty with her and heres what i have to report!
http://www.autosportracetech.com/RX-...eakDiagram.htm
On that diagram, at this point.. both 1" diameter hoses were lose and coated with oil (not thick but enough to make it slick
I wonder if that is it... the silicon hose job that was done on this car looks thorough and clean. Nylon heat resistant zip ties were cut to the stubs on every hose.. all the vacuum hoses except those 1" hoses were done in red... the main coupler for the Y pipe is a triple layer material... cleaned it up a bit but it looks good.
You think I might have found what I was looking for?
well this is the first time ive ever got down and dirty with her and heres what i have to report!
http://www.autosportracetech.com/RX-...eakDiagram.htm
On that diagram, at this point.. both 1" diameter hoses were lose and coated with oil (not thick but enough to make it slick
I wonder if that is it... the silicon hose job that was done on this car looks thorough and clean. Nylon heat resistant zip ties were cut to the stubs on every hose.. all the vacuum hoses except those 1" hoses were done in red... the main coupler for the Y pipe is a triple layer material... cleaned it up a bit but it looks good.
You think I might have found what I was looking for?
06-15-07, 02:07 AM
#12
:( nope
So I resecured hoses, rotated clips.. some clips that had loosened in one area were able to be switched for a tighter fit...
did the 1" dia hoses.. did the checks for the two valves.. put everything back together.. bam still got that idle issue and boost issue
Edit: A sign that there is air leakage is the presence of oily dirt on the aluminum casting around the hoses. New hose-clamps will set you back about $10 maximum for good ones. Note, clean up the oily dirt around the aluminum so that you will be able to see if these hoses start to leak again.
I definately saw this on both 1" dia hoses.. maybe I need to go buy more?
Could the vacuum loss in these hoses cause this much of an idle issue? seems more related to the turbos
did the 1" dia hoses.. did the checks for the two valves.. put everything back together.. bam still got that idle issue and boost issue
Edit: A sign that there is air leakage is the presence of oily dirt on the aluminum casting around the hoses. New hose-clamps will set you back about $10 maximum for good ones. Note, clean up the oily dirt around the aluminum so that you will be able to see if these hoses start to leak again.
I definately saw this on both 1" dia hoses.. maybe I need to go buy more?
Could the vacuum loss in these hoses cause this much of an idle issue? seems more related to the turbos
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