Well, not really. The volume test is done into a graduated cylinder without a restriction like the j-tube or pressure regulator.
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Lex/550 problems. Extremely lean
- Thread starter crimson88
- Start date
I'm not sure if this information would help your situation.
I am running SS LEX AFM replica with stock electronic and RC550 injectors. Car runs fine/smooth idle with the custom screw adjusted all the way in. When I back the screw out to get more air, the car idle rough and hesitated during boost. I turned the screw all the way in and the car runs great, again. I was thinking about installing the SAFC, raise the fuel pressure and then mess with the screw again.
I am running SS LEX AFM replica with stock electronic and RC550 injectors. Car runs fine/smooth idle with the custom screw adjusted all the way in. When I back the screw out to get more air, the car idle rough and hesitated during boost. I turned the screw all the way in and the car runs great, again. I was thinking about installing the SAFC, raise the fuel pressure and then mess with the screw again.
I have the SS replica and stock electronics with 550s and it ran fine under all conditions including the screw out. Idle has a little bit of a rumble all the way out, as a lot of unmetered air is creating a leaner mixture than TCCS planned. I later replaced my K&N soaked Supra electronics from Fuji with 1UZFE electronics from Fuji and there was no change in anything.
I'm here for justice. making my own extended screw today or tomorrow, because nobody on earth carries an m14x1.0 stud lol. I'm EXTREMELY lean under boost, like 18+ but idle and cruise are fine when not boosting. VF's are alright, no boost or vac leaks. I don't want to just pump up the SAFC correction, as it just adds fuel, and doesn't correct the fuel map.
because it's worse when the screw is back out as well as VF at constant 5v. at least with it I all the way in, the VF is around 3-3.5v
jet jock I know you don't hold peoples hands and like to give out cryptic metaphors instead of advice, so if you could actually shed light on the situation, please PM me
Maybe it's not cryptic. Maybe the issue at hand has several potential answers. Answering his question may force you to research and understand the systems in the 7m more in depth. Making your future trouble shootings easier.
I've read all I can find on the subject, and have been making this condition slowly better over the past month, staying out of boost. I'm not asking for someone to tell me what to do, but pointing in the right direction would be appreciated. If it's not the screw, I can only think of these things that would cause a lean condition...
- not enough fuel pressure (41 psi no vacuum)
- injectors not flowing enough (550's flow tested and rebuilt)
- pump isn't flowing enough (denso TT pump 12v)
like I said, the condition is worse when I back the screw out, better when I drive it in. with nothing else I've read having a positive outcome, this I the only thing left that WORKS. here's a full mod list, and yes it was running fine before I swapped it all
lexus AFM w/ 7mgte electronics
550cc injectors
SAFC-2
denso pump 12v wiring
AFPR @ 41psi no vac
2.5" IC pipes (DM kit)
3" turbo back exhaust
is300 coils
no vacuum, fuel, or boost leaks
- not enough fuel pressure (41 psi no vacuum)
- injectors not flowing enough (550's flow tested and rebuilt)
- pump isn't flowing enough (denso TT pump 12v)
like I said, the condition is worse when I back the screw out, better when I drive it in. with nothing else I've read having a positive outcome, this I the only thing left that WORKS. here's a full mod list, and yes it was running fine before I swapped it all
lexus AFM w/ 7mgte electronics
550cc injectors
SAFC-2
denso pump 12v wiring
AFPR @ 41psi no vac
2.5" IC pipes (DM kit)
3" turbo back exhaust
is300 coils
no vacuum, fuel, or boost leaks
unplug your safc and start over. here's a little hint, if its getting better when less air is given, perhaps you should double check everything that can give your engine air.
thanks indigo, I was thinking that since it's lean under boost only, it would have to be pre-turbo, post-AFM. I have a new accordian hose so the only place that leave air to get thru is the bypass channel.
and sorry to JetJock and Grim if I'm sounding like a stubborn kid with my head up my ass that refuses to listen, but Im sure that you weren't always supra gurus with all the knowledge and asked questions that seemed simple to other more experience members.
EDIT: I unlplugged the SAFC and it was not an improvement.
and sorry to JetJock and Grim if I'm sounding like a stubborn kid with my head up my ass that refuses to listen, but Im sure that you weren't always supra gurus with all the knowledge and asked questions that seemed simple to other more experience members.
EDIT: I unlplugged the SAFC and it was not an improvement.
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Quote from
http://rob.carlile.home.mchsi.com/lexus/lexus1.htmIV Testing/Problems Encountered
I had several problems with setting the car up, all of which were my fault, and were not in any way related to the upgrade itself, only my installation.
The first problem I had was that I could not get the FPR to raise the fuel pressure above 23 or 24 psi, stock being about 30. This was at idle with the vacuum hose connected. I was not familiar with the adjustment on the FPR and being the cautious sort that I am, I was too gentle with it at first, fearing I might break it. It turns out that where I thought the end of the adjustment was, was actually the beginning of it, and after a conversation with Reg, I decided to turn the adjustment screw a little harder (clockwise). Now it was starting to adjust! Reg had told me that his car was set to about 7 psi over stock so I set mine to 37 psi (at idle with vacuum hose attached).
My other problem, which was a real dumb oversight on my part, was that the two hose clamps holding the rubber hose connecting the "3000" pipe to the throttle body were loose, allowing metered air to escape under boost, which caused the car to run real rich under boost. I got enough black smoke out the rear that I looked like a mosquito fogging rig from South Fla. (Made $47 fogging for mosquitoes in two neighborhoods that day) After I got my band clamps tight, the car started running much better. Now I could think about adjusting the FPR and the AFM screw to optimize my mixture.
Reg told me that the car would idle best with the AFM screw all the way in, so this is where I started. Using the Montigney V/F meter as a guide, I finally settled on AFM screw at .607 (all the way in) and the fuel pressure set to about 28 psi (idle with vacuum). This is about 2 psi under stock. The car, however had a crappy idle, and I could not seem to tweak it right. I was sure, however, that I still had done something wrong, so for three days I kept looking at every vacuum hose, connector and widget I had touched to see if I could find the culprit.
After fogging the neighborhood for most that first day, I decided that it would not hurt to put in new plugs. I also found that the #6 plug wire had some insulation missing, so new wires were also a good idea. I ordered both (all factory Toyoto parts)and put them in when they arrived. Maybe this was my idling problem. But alas, it did not help. If anything, it was worse.
I had not changed the gaskets for the throttle body or the ISC valve so I decided to do this as I was running out of ideas. Well, it turned out the ISC valve gasket was leaking a little, so that when I put the car back together with new gaskets and tested it, the V/F meter showed a change in mixture. Well, at least I had affected it, so this was good. The car still would not idle smoothly, but now I was pretty sure it was somewhere in the ignition system.
Well, with the plugs and wires, I had managed to shoot myself in the foot again. The plugs are supposed to be pregapped, so I didn't check them, and just installed them. I had also installed the new plug wires at this time. The dyno runs I did the next day were with this setup, and a close examination of the curves indicated I still had ignition problems. After the gasket replacement, I thought about it some more and finally decided that I still had an ignition problem. I pulled the plugs, one at a time and checked the gaps. #3 was about .018 in. , while the rest were .025 to .030! Pregapped my ass. I regapped them to .031 and reinstalled them. I also found that the #2 plug boot had not been fully inserted into the hole and the contact was not fully snapped onto the plug and that the #3 plug wire was not fully engaged into the coil. Because the plug wires are all held in the looms when connected to the coils, this had restricted my access to the plugs. This made it hard to see what I was doing and to get the #2 boot fully inserted. I finally removed the all wires from the loom and put them back in one by one. When I put it back together this time and fired it up, the idle was much better. Now I could go back to the AFM screw and the FPR for my final adjustments.
I eventually settled on AFM screw at 0.385 (all the way out) and the fuel pressure set to 28 psi. With the system adjusted like this, the car idles smoothly and in the green on the VF meter. In fact, the VF readings look like they did before the mod. This was my tuning target, to make the car run the same, V/F-wise, as before the mod.
With it setup like this, I have no idea where my FCO is. My boost is set at 1.0 bar, and I have not hit it once since getting it tweaked in right. My peak hold boost gauge shows max boost during shifts is about 1.3 bar (19.1 psi) so it must be above this.
I also kept a close eye on my EGT gauge. The sensor is located after the turbo in the elbow before the downpipe, next to the O2 sensor. The highest EGT I have seen is 1400 F. Reg says my danger zone begins at about 1450 F, and that my readings are good. A note here about the location. A better location for the EGT sensor is before the turbo, which will read about 100 degrees F higher than after the turbo. It was not feasible to locate it here on my application, so the elbow was chosen as next best. The HKS sport turbo provides a port for mounting the sensor before the turbo, so eventually, I'll get it located there.
http://rob.carlile.home.mchsi.com/lexus/lexus1.htmIV Testing/Problems Encountered
I had several problems with setting the car up, all of which were my fault, and were not in any way related to the upgrade itself, only my installation.
The first problem I had was that I could not get the FPR to raise the fuel pressure above 23 or 24 psi, stock being about 30. This was at idle with the vacuum hose connected. I was not familiar with the adjustment on the FPR and being the cautious sort that I am, I was too gentle with it at first, fearing I might break it. It turns out that where I thought the end of the adjustment was, was actually the beginning of it, and after a conversation with Reg, I decided to turn the adjustment screw a little harder (clockwise). Now it was starting to adjust! Reg had told me that his car was set to about 7 psi over stock so I set mine to 37 psi (at idle with vacuum hose attached).
My other problem, which was a real dumb oversight on my part, was that the two hose clamps holding the rubber hose connecting the "3000" pipe to the throttle body were loose, allowing metered air to escape under boost, which caused the car to run real rich under boost. I got enough black smoke out the rear that I looked like a mosquito fogging rig from South Fla. (Made $47 fogging for mosquitoes in two neighborhoods that day) After I got my band clamps tight, the car started running much better. Now I could think about adjusting the FPR and the AFM screw to optimize my mixture.
Reg told me that the car would idle best with the AFM screw all the way in, so this is where I started. Using the Montigney V/F meter as a guide, I finally settled on AFM screw at .607 (all the way in) and the fuel pressure set to about 28 psi (idle with vacuum). This is about 2 psi under stock. The car, however had a crappy idle, and I could not seem to tweak it right. I was sure, however, that I still had done something wrong, so for three days I kept looking at every vacuum hose, connector and widget I had touched to see if I could find the culprit.
After fogging the neighborhood for most that first day, I decided that it would not hurt to put in new plugs. I also found that the #6 plug wire had some insulation missing, so new wires were also a good idea. I ordered both (all factory Toyoto parts)and put them in when they arrived. Maybe this was my idling problem. But alas, it did not help. If anything, it was worse.
I had not changed the gaskets for the throttle body or the ISC valve so I decided to do this as I was running out of ideas. Well, it turned out the ISC valve gasket was leaking a little, so that when I put the car back together with new gaskets and tested it, the V/F meter showed a change in mixture. Well, at least I had affected it, so this was good. The car still would not idle smoothly, but now I was pretty sure it was somewhere in the ignition system.
Well, with the plugs and wires, I had managed to shoot myself in the foot again. The plugs are supposed to be pregapped, so I didn't check them, and just installed them. I had also installed the new plug wires at this time. The dyno runs I did the next day were with this setup, and a close examination of the curves indicated I still had ignition problems. After the gasket replacement, I thought about it some more and finally decided that I still had an ignition problem. I pulled the plugs, one at a time and checked the gaps. #3 was about .018 in. , while the rest were .025 to .030! Pregapped my ass. I regapped them to .031 and reinstalled them. I also found that the #2 plug boot had not been fully inserted into the hole and the contact was not fully snapped onto the plug and that the #3 plug wire was not fully engaged into the coil. Because the plug wires are all held in the looms when connected to the coils, this had restricted my access to the plugs. This made it hard to see what I was doing and to get the #2 boot fully inserted. I finally removed the all wires from the loom and put them back in one by one. When I put it back together this time and fired it up, the idle was much better. Now I could go back to the AFM screw and the FPR for my final adjustments.
I eventually settled on AFM screw at 0.385 (all the way out) and the fuel pressure set to 28 psi. With the system adjusted like this, the car idles smoothly and in the green on the VF meter. In fact, the VF readings look like they did before the mod. This was my tuning target, to make the car run the same, V/F-wise, as before the mod.
With it setup like this, I have no idea where my FCO is. My boost is set at 1.0 bar, and I have not hit it once since getting it tweaked in right. My peak hold boost gauge shows max boost during shifts is about 1.3 bar (19.1 psi) so it must be above this.
I also kept a close eye on my EGT gauge. The sensor is located after the turbo in the elbow before the downpipe, next to the O2 sensor. The highest EGT I have seen is 1400 F. Reg says my danger zone begins at about 1450 F, and that my readings are good. A note here about the location. A better location for the EGT sensor is before the turbo, which will read about 100 degrees F higher than after the turbo. It was not feasible to locate it here on my application, so the elbow was chosen as next best. The HKS sport turbo provides a port for mounting the sensor before the turbo, so eventually, I'll get it located there.
I was just re-reading some comments. Go read about "suction" and "pressure" sides of a liquid pump.