Lean Idle condition; HELP
03-05-12, 10:40 PM
#26
talking head
you may need to pull the loom up from the ecu,, about 1 to 2 feet up loom there is a series of crimped joins
2 of them are earth bundles ,, and relate to the staging bug,, and you resolder these and attach another earth cable to it to get rid of the staging hesitation
- no help to you-
but the third join is a 12V bus,, and goes to the injectors ,, its likely you may have some dry join issue here,, and that may explain the sporadic condition
it may just pay to pull open the loom and resolder all of these joins ,, may do nothing,, or may just fix a whole series of bugs
2 of them are earth bundles ,, and relate to the staging bug,, and you resolder these and attach another earth cable to it to get rid of the staging hesitation
- no help to you-
but the third join is a 12V bus,, and goes to the injectors ,, its likely you may have some dry join issue here,, and that may explain the sporadic condition
it may just pay to pull open the loom and resolder all of these joins ,, may do nothing,, or may just fix a whole series of bugs
03-08-12, 08:08 PM
#28
Checked the BAC. opens with 12v per FSM, but measures 12.8 ohms and FSM lists 10.7-12.3 for serviceability. I highly doubt .5 ohms is going to make much of a difference considering it's an open or closed device. Any more ideas people?
03-08-12, 09:11 PM
#29
Took the whole manifolds apart again. No vacuum leaks. Made sure everything is buttoned up. Still not enough fuel at idle. Driving around everything is normal. Full throttle I get typical too rich NA 10:1 AFRs. I'm stumped... If I close off the return line with vice grips it starts to richen up. I'm at an utter loss of ideas here.
03-09-12, 12:15 AM
#31
It has an Atkins "Stage 2 street port." What ever the hell that means. When I put the header on it I inspected the exhaust port. It has turbo rotor housings and the port is relatively small. They just port matched the exhaust sleeves. I cant imagine that the port job is so big that the stock over rich injectors cannot keep up. Especially considering it runs so rich at WOT and 8k RPMs. I tore everything down today cleaned everything resealed the manifolds, still same issue. It idles at 1500 rpm and nothing I do will richen it up. 18-19:1 AFRs.
When I took it to Lucky 7 they threw in a FPR and cranked fuel pressure up to 80 psi and it started to idle. They suggested I up the injectors to 650's on the primaries.After I left I went to Vatozone and threw in a can of Seafoam and it ran perfectly for a week. Then it just went lean again. That is what lead me to believe it was a failing injector. Replaced the injectors with another set of known working S5 NA injectors and the issue persists.
I "borrowed" my roommates AEM FPR and I'm going to throw it in tomorrow and see if that will fix it. Lucky 7 said I shouldn't do that because cranking up the fuel pressure could harm the stock injectors and possibly make it run too lean up top(due to the injector fighting against the pressure). At this point I'm almost willing to swap in larger primary injectors just to see if that fixes it.
EDIT:
Side note the cat has not glown since I got the timing fixed. Though the lean condition has wrecked havok on my cat with less than 4k on it, and now it sounds like there are marbels inside it.
What does this plug go to?
When I took it to Lucky 7 they threw in a FPR and cranked fuel pressure up to 80 psi and it started to idle. They suggested I up the injectors to 650's on the primaries.After I left I went to Vatozone and threw in a can of Seafoam and it ran perfectly for a week. Then it just went lean again. That is what lead me to believe it was a failing injector. Replaced the injectors with another set of known working S5 NA injectors and the issue persists.
I "borrowed" my roommates AEM FPR and I'm going to throw it in tomorrow and see if that will fix it. Lucky 7 said I shouldn't do that because cranking up the fuel pressure could harm the stock injectors and possibly make it run too lean up top(due to the injector fighting against the pressure). At this point I'm almost willing to swap in larger primary injectors just to see if that fixes it.
EDIT:
Side note the cat has not glown since I got the timing fixed. Though the lean condition has wrecked havok on my cat with less than 4k on it, and now it sounds like there are marbels inside it.
What does this plug go to?
03-09-12, 12:07 PM
#32
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connector is for the aux fan on the turbo and automatics.
have you tried a different AFM? 20B?
have you tried a different AFM? 20B?
03-09-12, 04:39 PM
#34
Just put in AEM FPR. Cranking up the fuel pressure helps, but not much. It idles at 1500 rpm 16:1 AFR's. Then when I adjust the TPS to lower the idle: right when it reaches about 1300 RPM it suddenly goes full lean again -19:1- and idle drops to 500-700 rpm.
Talkin' to myself! Will it run again?
http://www.youtube.com/watch?v=PGUU7CiK7YU
lol
Talkin' to myself! Will it run again?
http://www.youtube.com/watch?v=PGUU7CiK7YU
lol
03-10-12, 12:05 AM
#36
Opened up the tape on the 4 grounds on the harness. soldered them at the unions and added 2 ground straps and bolted them to the ECU mount. Same issues, except now when I turn the headlights on idle goes up and it richen's up....
03-10-12, 08:11 PM
#37
4 green wires at the ECU all see 12V exactly with key on. Pulled off the whole intake manifold. confirmed small street port. nothing big enough to cause a lean idle condition. Swapped in a known working AFM and no change. Swapped in working N350, no change. I'm running out of ideas. All I'm thinking is that it's the harness, but everything tests perfectly. Does anyone have any ideas? The instrument cluster is not stock it's a hodgepoge of s4 & S5 stuff, could that affect something somehow?
03-10-12, 08:29 PM
#38
Rotary Freak
IF your car still has the airpump and ACV in working condition, then it's as normal as applle pie to have a lean idle. Common sense thing if you know how the car works.
IF no ACV or airpump..........disregard the above. I assumed you had the airpump/acv being in california and all.
I've no idea why one would set the timing to zero. Got me why.
TPS do are not made for idle adjustments. TPS are used by the ECU for determining certain zones of operation for the ECU and also for operating the relief and switching solenoids which control the ACV on a NORMAL STOCK rx7. read training manual.
TPS should not be set until the engine is fully hot or the fast idle cam has seperated from its roll pin.
IF no ACV or airpump..........disregard the above. I assumed you had the airpump/acv being in california and all.
I've no idea why one would set the timing to zero. Got me why.
TPS do are not made for idle adjustments. TPS are used by the ECU for determining certain zones of operation for the ECU and also for operating the relief and switching solenoids which control the ACV on a NORMAL STOCK rx7. read training manual.
TPS should not be set until the engine is fully hot or the fast idle cam has seperated from its roll pin.
03-10-12, 08:43 PM
#39
AVC and Air pump are on the car, but 19:1 AFR's on my wideband are not normal. Also the narrow band I had hooked up, also, confirms it is not entering open loop at idle like it should. It is off the map lean on both my narrow band AFR gauge and on my wideband AFR gauge. Lastly, it will not idle on it's own, at all. It is so lean it will not idle below 1500 RPM on it's own and I can't figure out why.
03-10-12, 08:55 PM
#40
Rotary Freak
I've had a wideband (Zeitronix) on all three of my RX for seven plus yrs and all of them show afr at IDLE in the 16-17 afr range, which is as NORMAL as can be on ANY rx7 that is STOCK with airpump and ACV working.
The air from the airpump travels thru the ACV ..........to the exhaust ports on the ENGINE then on to the rest of the exhasut. The 02 sensor is WHERE? Itl's located after the exhaust ports. What happens when you mix fresh air with the exhaust gasses coming out of the engine?????? uh, yes, it dilutes the exhast gasses making the O2 sensor read LEANER than what the actual afr is.
The air from the airpump travels thru the ACV ..........to the exhaust ports on the ENGINE then on to the rest of the exhasut. The 02 sensor is WHERE? Itl's located after the exhaust ports. What happens when you mix fresh air with the exhaust gasses coming out of the engine?????? uh, yes, it dilutes the exhast gasses making the O2 sensor read LEANER than what the actual afr is.
03-10-12, 09:01 PM
#42
Rotary Freak
IF you really want to know what the real afr is on that car.............cut the airpump belt.......or pull the airpump belt off..............of simply pull the elect plug off the RELIEF solenoid. The afr will magically get richer. Like in the 13afr range..........cause the airpump air will not go to the exhaust ports anymore, it'll all get sent into the silencer in the right front fender area.
That relief solenoid only applies to a car with the TPS set correctly and the rpms in the 750-800 rpm range at idle.
That relief solenoid only applies to a car with the TPS set correctly and the rpms in the 750-800 rpm range at idle.
03-10-12, 09:08 PM
#44
Rotary Freak
Warm the car up fully. Measure the output of the TPS with the rpms well under 1100 rpm, preferably around 750-800 rpm. Read the afr on your wideband. Now pull the elect plug off the relief solenoid.
Now look at the afr. It should now show much richer. A 13afr is NORMAL in this condition....becasue there will be no airpump air mixing with the exhaust gasses coming out of the exhasut port no 'mo.
IF the afr is not a lot richer doing this..........your acv /TPS whatever is not installed correctly. So pull the belt off the airpump and then look at the afr. The must be a lot richer now than with the pump running.
Timing should be done with a timing light with a fully HOT engine and the idle MUST (DID I SAY must???) be under 1100 rpms setting it. The timing is supposed to be what the online manual says it should be...........five lead........five trail. Just set it using the LEAD and all will be just fine and dandy as for the timing. Wast of time looking at the trail imho.
Now look at the afr. It should now show much richer. A 13afr is NORMAL in this condition....becasue there will be no airpump air mixing with the exhaust gasses coming out of the exhasut port no 'mo.
IF the afr is not a lot richer doing this..........your acv /TPS whatever is not installed correctly. So pull the belt off the airpump and then look at the afr. The must be a lot richer now than with the pump running.
Timing should be done with a timing light with a fully HOT engine and the idle MUST (DID I SAY must???) be under 1100 rpms setting it. The timing is supposed to be what the online manual says it should be...........five lead........five trail. Just set it using the LEAD and all will be just fine and dandy as for the timing. Wast of time looking at the trail imho.
03-10-12, 09:18 PM
#46
upping the fuel pressure isn't as harmful as they led you to believe, but it is a bandaid. try to find another AFM, i have come across a few lately that have lost their calibration and caused lean issues. bad TPS, bad fuel filter or bad pump also come to mind.
also try checking for leaks with carb cleaner, vacuum leaks will cause it to run lean.
also try checking for leaks with carb cleaner, vacuum leaks will cause it to run lean.
Last edited by RotaryEvolution; 03-10-12 at 09:23 PM.
03-10-12, 09:23 PM
#47
Rotary Freak
TPS determines if the Relief solenoid (BLUE colored sucker on the left side of the engine) is energized and porting vacuum to the ACV at idle. This results in the ACV porting airpump air to the EXHAUST PORT ON THE ENGINE prior to the exhaust manifold. This air is diluting the exhaust gasses resulting in the high afr numbers your seeing. THIS IS THE WAY THE CAR WAS designed to work.
\
On a working stk car the removal of the plug from the relief soleoid will result in the ACV exhausting all the airpump air out that LARGE nipple on the outboard side of the ACV and into the hose that is connected to that nipple and sent to the silencer in the right fender resulting in NO air going into the exhaust ports/manifold .......meaning the wideband/narrow band will now read the REAL afr of the engine (approx 13afr at idle).
O2 is in open loop on all series four and five at idle and speeds generally under 1500 rpm. There's no way it can go into closed loop at idle unless a lot of trickery is done. This open or closed loop has zip to do with your high afr numbers at idle. Forget about closed loop/open loop.
I've no idea why your car won't idle. The timiing should be 5*atdc LEAD with the rpms under 1100 rpm preferably around 750-800 rpm. The TPS should be outputting one volt dc at idle.
Misrouted vacuum lines........loose fittings......all sorts of stuff can cause no or lack of idle . IDLE being defined as 750-800 rpm in general. NEVER IS A RPM OVER 1000 a idle speed imho.
ECU will all by it's lonesome advance the timing if the rpms get over approx 1100 rpm making using a timing light useless for setting the timing if the rpms are over 1100 rpm
03-10-12, 09:28 PM
#48
Rotary Freak
A shot ACV is one whos diaphrams are ruined. But this would not result in high afr figures. A shot diaphram would result in NO air going to the exhaust ports and therefore no dilution of the exhaust gasses seen by the 02 sensors.
Pull the airpump belt OFF and with a fully hot engine read the afr/gauges.
Pull the airpump belt OFF and with a fully hot engine read the afr/gauges.
03-10-12, 09:37 PM
#49
upping the fuel pressure isn't as harmful as they led you to believe, but it is a bandaid. try to find another AFM, i have come across a few lately that have lost their calibration and caused lean issues. bad TPS, bad fuel filter or bad pump also come to mind.
also try checking for leaks with carb cleaner, vacuum leaks will cause it to run lean.
also try checking for leaks with carb cleaner, vacuum leaks will cause it to run lean.
I'm about to throw everything in the trash and go carburetor. I've been trying to get this car running for 13 months now. And now that some lady decided to total my FB I need this POS to work. All vacuum lines are run correctly according to the FSM. The only thing I can think is that it's not firing the primary injectors for some unknown reason or the ACV is broken internally somewhere, and as Mike suggested is causing a vacuum leak into the manifold.
Hailers. I will put it all back together tomorrow. It's apart right now because I wanted to check the port job to confirm or deny Lucky 7's guess at what the problem was.
03-10-12, 09:40 PM
#50
Rotary Freak
Engine does NOT have to be running to adjust a TPS to output one volt dc. The engiine DOES need to be fully hot. The throttle needs to be fully CLOSED meaning the fast ldle cam must be seperated from it's roll pin.
I agree a afm that has been fiddled with will and can result in a lean idle/no idle.
All I'm saying is .............if you have a working airpump and working ACV and are reading the afr with them working..........you have NO CLUE what the real afr is and therefore don't know if your too lean or too rich.
In general my afr is 13afr at idle with the ACV deactivated (blue plug off the relief solenoid resulting in no air going to the exhaust ports) and it's in the 16's and 17's with the plug on the relief solenoid which results in air going to the exhaust ports.
Make sense? Does to me..
I agree a afm that has been fiddled with will and can result in a lean idle/no idle.
All I'm saying is .............if you have a working airpump and working ACV and are reading the afr with them working..........you have NO CLUE what the real afr is and therefore don't know if your too lean or too rich.
In general my afr is 13afr at idle with the ACV deactivated (blue plug off the relief solenoid resulting in no air going to the exhaust ports) and it's in the 16's and 17's with the plug on the relief solenoid which results in air going to the exhaust ports.
Make sense? Does to me..