S4 NA goes lean on steady state cruise?
01-03-10, 12:19 AM
#27
IF you have the airpum and ACV functional, then try this. Remove the BLUE electrical plug from the Relief solenoid. That act will cause the ACV to dump all the airpump air into the silencer in the right front fender instead of the exhaust ports.
Now go for a ride like that and compare it with the results you were getting before. If it still goes lean then it's not the airpump air going thru the ACV. Simple as that. Like mentioned above, it's probably the airpum air causing the *lean problem* when the blue connector is on the relief solenoid.
If so, then it's not really a lean mixture problem at all in any way.
IF you have a RTEK 2.0, you can look at the page that shows the switching...relief solenoids conditoin. I'm fairly sure if you drive along at a steady speed, the RELIEF will not show to be energized, but the moment you let off the throttle a bit it will get energized (meaning acv air will go to the exhaust ports and now mix with exhaust gas and cause the 02 sensor to show...lean). I'm fairly sure about that. Plus maybe the Port air solenod going open also. One or the other. Hedge, hedge, hedge, hedge.
Now go for a ride like that and compare it with the results you were getting before. If it still goes lean then it's not the airpump air going thru the ACV. Simple as that. Like mentioned above, it's probably the airpum air causing the *lean problem* when the blue connector is on the relief solenoid.
If so, then it's not really a lean mixture problem at all in any way.
IF you have a RTEK 2.0, you can look at the page that shows the switching...relief solenoids conditoin. I'm fairly sure if you drive along at a steady speed, the RELIEF will not show to be energized, but the moment you let off the throttle a bit it will get energized (meaning acv air will go to the exhaust ports and now mix with exhaust gas and cause the 02 sensor to show...lean). I'm fairly sure about that. Plus maybe the Port air solenod going open also. One or the other. Hedge, hedge, hedge, hedge.
Does the Intake Air Temp affect anything related to fueling? I dont seem to have an IAT signal from my AFM.
01-03-10, 09:07 AM
#30
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*I'll try it, but when the car goes lean I can feel hesitating and losing power. I'll also check it out on the RTEK.
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Yeah, in that case it probably IS going lean and not the acv/airpump.
How does it drive if you disconnect the 02 sensor? The stock 02 sensor is the one I mean, not any wideband one you have. And if you do have a wideband simulating the normal 02 sensor, how 'bout disconnecting that simulated signal also. Then go drive it and see if it's lean.
How's this for a possibility?.... Your fuel *maps* are too lean and when your driving at a steady speed the 02/ECU goes into closed loop. When in closed loop the ECU trys to either bring up or bring down the mixture to get close to 14.7afr, and lets say in your case it is doing that. Like making the mixture richer to reach 14.7 on your car. Then when exitiing closed loop it starts hesitating becacue it now goes out of closed loop to the leaner mixture your maps are at?
I really should go back and read this thread from the start instead of writing the above. No time to do so. Just a thought.
EDIT: I went back and read the first post. Seems you car ran LEAN and you richened it up as best you could with the RTEK 2.0 and the problem persists. I'd get a pair of 550s and put 'em in the primary spots. Just ignore my drivel in the paragraphs above since it does not relate to your problem.
EDIT: That said, the following from you in your first post does sound like the airpump air causing the lean reading: ****I have an S4 NA that will randomly lean out from ~15 AFR to ~19-20 AFR while cruising. When thes happens if I give it more or less gas it will richen back up to normal. This happens at freeway speeds mostly*********. And I mean just under that condition, NOT any lean condition when going pedal to the floor. THAT would be another thing, like too small injectors etc.
EDIT: The following from you confused me: **Also I have had to use my RTEK 2.0 to lean the car out to ~13:1 in open loop. Without the RTEK the car would run ~18-19:1 under load.*** The figures 18-19 afr are lean mixtures and your talking about using the RTEK2.0 to lean the mixture out to 13:1. Must be a typo or something there. You meant you richened it up using the RTEK2.0.
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Yeah, in that case it probably IS going lean and not the acv/airpump.
How does it drive if you disconnect the 02 sensor? The stock 02 sensor is the one I mean, not any wideband one you have. And if you do have a wideband simulating the normal 02 sensor, how 'bout disconnecting that simulated signal also. Then go drive it and see if it's lean.
How's this for a possibility?.... Your fuel *maps* are too lean and when your driving at a steady speed the 02/ECU goes into closed loop. When in closed loop the ECU trys to either bring up or bring down the mixture to get close to 14.7afr, and lets say in your case it is doing that. Like making the mixture richer to reach 14.7 on your car. Then when exitiing closed loop it starts hesitating becacue it now goes out of closed loop to the leaner mixture your maps are at?
I really should go back and read this thread from the start instead of writing the above. No time to do so. Just a thought.
EDIT: I went back and read the first post. Seems you car ran LEAN and you richened it up as best you could with the RTEK 2.0 and the problem persists. I'd get a pair of 550s and put 'em in the primary spots. Just ignore my drivel in the paragraphs above since it does not relate to your problem.
EDIT: That said, the following from you in your first post does sound like the airpump air causing the lean reading: ****I have an S4 NA that will randomly lean out from ~15 AFR to ~19-20 AFR while cruising. When thes happens if I give it more or less gas it will richen back up to normal. This happens at freeway speeds mostly*********. And I mean just under that condition, NOT any lean condition when going pedal to the floor. THAT would be another thing, like too small injectors etc.
EDIT: The following from you confused me: **Also I have had to use my RTEK 2.0 to lean the car out to ~13:1 in open loop. Without the RTEK the car would run ~18-19:1 under load.*** The figures 18-19 afr are lean mixtures and your talking about using the RTEK2.0 to lean the mixture out to 13:1. Must be a typo or something there. You meant you richened it up using the RTEK2.0.
01-03-10, 05:41 PM
#31
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Remember, this is not me posting out of my ****, I actually did this and have experience driving a car after these mods. On top of that, I had an S5 vert, so if an N/A engine was fine at low revs in that pig, it will be fine in an S4 coupe which is 200lbs lighter.
01-03-10, 11:02 PM
#32
*I'll try it, but when the car goes lean I can feel hesitating and losing power. I'll also check it out on the RTEK.
************************************************** ************************
Yeah, in that case it probably IS going lean and not the acv/airpump.
How does it drive if you disconnect the 02 sensor? The stock 02 sensor is the one I mean, not any wideband one you have. And if you do have a wideband simulating the normal 02 sensor, how 'bout disconnecting that simulated signal also. Then go drive it and see if it's lean.
How's this for a possibility?.... Your fuel *maps* are too lean and when your driving at a steady speed the 02/ECU goes into closed loop. When in closed loop the ECU trys to either bring up or bring down the mixture to get close to 14.7afr, and lets say in your case it is doing that. Like making the mixture richer to reach 14.7 on your car. Then when exitiing closed loop it starts hesitating becacue it now goes out of closed loop to the leaner mixture your maps are at?
I really should go back and read this thread from the start instead of writing the above. No time to do so. Just a thought.
EDIT: I went back and read the first post. Seems you car ran LEAN and you richened it up as best you could with the RTEK 2.0 and the problem persists. I'd get a pair of 550s and put 'em in the primary spots. Just ignore my drivel in the paragraphs above since it does not relate to your problem.
EDIT: That said, the following from you in your first post does sound like the airpump air causing the lean reading: ****I have an S4 NA that will randomly lean out from ~15 AFR to ~19-20 AFR while cruising. When thes happens if I give it more or less gas it will richen back up to normal. This happens at freeway speeds mostly*********. And I mean just under that condition, NOT any lean condition when going pedal to the floor. THAT would be another thing, like too small injectors etc.
EDIT: The following from you confused me: **Also I have had to use my RTEK 2.0 to lean the car out to ~13:1 in open loop. Without the RTEK the car would run ~18-19:1 under load.*** The figures 18-19 afr are lean mixtures and your talking about using the RTEK2.0 to lean the mixture out to 13:1. Must be a typo or something there. You meant you richened it up using the RTEK2.0.
************************************************** ************************
Yeah, in that case it probably IS going lean and not the acv/airpump.
How does it drive if you disconnect the 02 sensor? The stock 02 sensor is the one I mean, not any wideband one you have. And if you do have a wideband simulating the normal 02 sensor, how 'bout disconnecting that simulated signal also. Then go drive it and see if it's lean.
How's this for a possibility?.... Your fuel *maps* are too lean and when your driving at a steady speed the 02/ECU goes into closed loop. When in closed loop the ECU trys to either bring up or bring down the mixture to get close to 14.7afr, and lets say in your case it is doing that. Like making the mixture richer to reach 14.7 on your car. Then when exitiing closed loop it starts hesitating becacue it now goes out of closed loop to the leaner mixture your maps are at?
I really should go back and read this thread from the start instead of writing the above. No time to do so. Just a thought.
EDIT: I went back and read the first post. Seems you car ran LEAN and you richened it up as best you could with the RTEK 2.0 and the problem persists. I'd get a pair of 550s and put 'em in the primary spots. Just ignore my drivel in the paragraphs above since it does not relate to your problem.
EDIT: That said, the following from you in your first post does sound like the airpump air causing the lean reading: ****I have an S4 NA that will randomly lean out from ~15 AFR to ~19-20 AFR while cruising. When thes happens if I give it more or less gas it will richen back up to normal. This happens at freeway speeds mostly*********. And I mean just under that condition, NOT any lean condition when going pedal to the floor. THAT would be another thing, like too small injectors etc.
EDIT: The following from you confused me: **Also I have had to use my RTEK 2.0 to lean the car out to ~13:1 in open loop. Without the RTEK the car would run ~18-19:1 under load.*** The figures 18-19 afr are lean mixtures and your talking about using the RTEK2.0 to lean the mixture out to 13:1. Must be a typo or something there. You meant you richened it up using the RTEK2.0.
EVERY thime the car does this I can feel it in the car, so I am pretty certain it is not the airpump, but I will check it out by removing the blue plug you outlined. It does this while cruising at freeway speeds. The open loop lean issue is a seperate issue, but perhaps both are related.
01-04-10, 09:40 AM
#33
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I'm probably retarded, but I'd try the 550's in the primarys. If their in the secondarys then the lean during cruise won't go away if you've already richened the fuel maps to their max. Secondarys only work under Load and over approx 3800rpm.
I agree now that the airpump isn't causing the lean conditon where the car ....can't think of the right words right now......hesitates might be the word. Sort of bumps along and hesitates when lean condition.
We assume the RTEK is set for 460's right now and not some other setting. Good luck.
I agree now that the airpump isn't causing the lean conditon where the car ....can't think of the right words right now......hesitates might be the word. Sort of bumps along and hesitates when lean condition.
We assume the RTEK is set for 460's right now and not some other setting. Good luck.
01-04-10, 12:48 PM
#34
I'm probably retarded, but I'd try the 550's in the primarys. If their in the secondarys then the lean during cruise won't go away if you've already richened the fuel maps to their max. Secondarys only work under Load and over approx 3800rpm.
I agree now that the airpump isn't causing the lean conditon where the car ....can't think of the right words right now......hesitates might be the word. Sort of bumps along and hesitates when lean condition.
We assume the RTEK is set for 460's right now and not some other setting. Good luck.
I agree now that the airpump isn't causing the lean conditon where the car ....can't think of the right words right now......hesitates might be the word. Sort of bumps along and hesitates when lean condition.
We assume the RTEK is set for 460's right now and not some other setting. Good luck.
I agree with that reasoning of the 550 placement. I have a track day this weekend, so I am probably going to just put the 550s in as seconadaries for right now because of time and I'd want all new gaskets which I would need to order. This should fix my open loop problem anyway, which I care more about at this point.
Hesitation is a great word to describe what I feel on a steady state cruise.
Also, I am fairly certain this problem is across both rotors. The plugs out of both rotors have ALWAYS looked about identical By my estimation, if I was adding 50% fuel globally, and only had this problem on one rotor only the plugs would look close to normal out of one rotor, and the other would have fouled/rich looking plugs.
01-04-10, 02:23 PM
#35
It sure does sound like the problem I have had. Are you still on the stock fuel pump/wiring? I just rewired my pump and didn't notice any weird lean BS, but it was rich all over the entire rpm.
Basically when your cruising it goes hella lean, then loses some power, and once you fiddle with the throttle a little it comes back to life.
There was also threads about it in the RTEK forum. Its got me thinking its the RTEK...
https://www.rx7club.com/showpost.php...3&postcount=20
https://www.rx7club.com/showthread.p...ight=lean+fuel
Basically when your cruising it goes hella lean, then loses some power, and once you fiddle with the throttle a little it comes back to life.
There was also threads about it in the RTEK forum. Its got me thinking its the RTEK...
https://www.rx7club.com/showpost.php...3&postcount=20
https://www.rx7club.com/showthread.p...ight=lean+fuel
01-13-10, 08:23 PM
#36
UPDATE -
Put in 2 new 550 cc injectors in the secondaries. This helped, but not enough.
I then replaced my AFM with another used one. This solved the problem, as well as my lean open loop condition.
In comparing my malfunctioning AFM and my new one, they both tested perfectly according to the FSM and both were factory sealed - go figure.
Now I just have to retune the thing
Put in 2 new 550 cc injectors in the secondaries. This helped, but not enough.
I then replaced my AFM with another used one. This solved the problem, as well as my lean open loop condition.
In comparing my malfunctioning AFM and my new one, they both tested perfectly according to the FSM and both were factory sealed - go figure.
Now I just have to retune the thing
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