lexus afm +550cc injector mod not working. using stock AFM housing.

[Rollus]

Plus, in limp mode, AFR should be proportionnal to throttle position.

I guess for knock it is not really limp mode, but a failsafe ignition timing. In any case, every code has to be adressed in order to have good settings from ECU.

 

[chtulu]

I really appreciate all the effort everyone is putting in on this thread. Another question I have is if I just buy the HKS VPC to get rid of the AFM issues can that be used in conjuction with the HKS FCD and AFPR to tune it enough before going complete stand alone? Or do I need a SAFC II WITH the hks VPC?

 

[Nick M]

The AFM issues are not because of the AFM, they are because of other things wrong. Unless the reflector or LED is soaked in K&N oil.

 

[chtulu]

The AFM issues are not because of the AFM, they are because of other things wrong. Unless the reflector or LED is soaked in K&N oil.

Could you name some things I could be looking at? Unless the knock sensor code 52 can directly affect the code 32? I'm trying to isolate one problem at a time here, if possible. I test the AFM and the resistance is at 4900 at about 34-38 degrees F outside. Where should I look next?

 

[chtulu]

Ugh, nevermind about anything on this thread. The Code is 34. My mechanic didn't read the diagnostic right. So now It seems i have a boost leak somewhere. But with such a big turbo at 15lbs I'm guessing its coming from my BoV.

 

[chtulu]

So I cleared the sputtering issue at WOT. Wasn't getting enough air via the stock AFM housing. Lexus AFM housing now gives me super lean readings at idle but I can boost all day long with WOT around 10.1 A/F ratio. Any idea why I would be leaning out so hard just sitting there?

 

[atmperformance]

you can play with fuel pressure and the housing adjustment screw that will most likely be under epoxy.

 

[Rollus]

I would set FP to stock spec, and play with AFM.

Don't forget to reset ECU learned fuel trim by pulling the EFI fuse after modifications on the fuel/air metering system.

 

[chtulu]

Ok,

Screw is all the way in, and i adjusted the FP to 30psi idle without vacuum. took out the EFI for 5 minutes and tried again. How long does it usually for the ecu to adjust it's map? Because it hasn't done anything yet when I did this the first time.

 

[Nick M]

So now It seems i have a boost leak somewhere. But with such a big turbo at 15lbs I'm guessing its coming from my BoV.

You don't necessarily have an intake leak. With a big turbo you can easily hit overboost fuel cut and it has nothing to do with a leak. The larger housing slows the frequency raising the point at which fuel cut occurs.

Ok,

Screw is all the way in, and i adjusted the FP to 30psi idle without vacuum. took out the EFI for 5 minutes and tried again. How long does it usually for the ecu to adjust it's map? Because it hasn't done anything yet when I did this the first time.

If the screw is all the way, fuel cut happens sooner rather than later. The meter is seeing far more air than a CT-26 can deliver. And for all I know, your fuel pump is not delivering volume. There isn't actually enough information in your posts. There are things to look at from what you have given. If the screw is all the way in, you should not be lean at idle, not even close. 30 psi with the vacuum disconnected is not right. That is fine when there is vacuum on the regulator.

 

[chtulu]

You don't necessarily have an intake leak. With a big turbo you can easily hit overboost fuel cut and it has nothing to do with a leak. The larger housing slows the frequency raising the point at which fuel cut occurs.



If the screw is all the way, fuel cut happens sooner rather than later. The meter is seeing far more air than a CT-26 can deliver. And for all I know, your fuel pump is not delivering volume. There isn't actually enough information in your posts. There are things to look at from what you have given. If the screw is all the way in, you should not be lean at idle, not even close. 30 psi with the vacuum disconnected is not right. That is fine when there is vacuum on the regulator.

I apologize, i meant 30psi with vacuum connect at idle per TSRM. http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=73

The lexus AFM with the screw all the way in or out doesn't seem to make a huge difference at idle. I don't hit fuel cut at all with the lexus afm housing. I just run really lean at idle.

 

[jetjock]

... I test the AFM and the resistance is at 4900 at about 34-38 degrees F outside. ...

Not that I think your AFM is bad but you're not testing the part of it that really matters by doing the above. Second, many of these engines run lean at idle. Why care? You don't drive it there.

 

[chtulu]

Not that I think your AFM is bad but you're not testing the part of it that really matters by doing the above. Second, many of these engines run lean at idle. Why care? You don't drive it there.

I realize Im not hurting it idling lean, but when it dips to 19-20 it almost dies and blows out smoke. It's more of making it somewhat driveable. especially sitting at a stop light. I also don't have a filter on it currently. Would the restriction from a air filter help at all?

 

[jetjock]

No filter? Just the AFM exposed? If so I hope it's not in the stock location near the cooling fan...

 

[Suprapowaz!(2)]

What's it doing cruising around. Where are the AFR's, and what is Vf1 displaying? I'd work on getting the idle and cruise happy first. I wouldn't worry about WOT so much right now.

Having the lex afm screw all the way out and fuel pressure that 30psi vac unplugged will lean things out quite a bit at idle and closed loop. But that's how you're maintaining 10.1:1 at WOT with that big turbo. That's still rich though. I would concentrate on getting closed loop to run acceptable AFR's. That's going to leave you with a super rich condition at WOT. It won't run good under heavy load.

You're going to have to go with some kind of piggyback to pull fuel in open loop.

Will you be doing all of this yourself, or having some kind of assistance? Where are you located? Maybe someone in your area be able to help you.

 

[chtulu]

Cruise is fine. 14.6 ish if I'm keeping a steady pace. Partial boost goes to 12 to 12.5 and wot is 10.1. It runs great besides the idle. If it were the tps I assume I'd get a cel for it? Maybe I'm naive in that area.

I have screwed the lexus afm screw all the way in to try and reduce air flow as well as turned the fuel to 30 psi with vacuum connected. Even cranking the fuel to 50 psi doesn't change the idle at all.

I'm in washington state. I haven't really found anyone knowledgeable yet for help on this car. I'm thinking of just buying a safc neo and manually changing the fuel trim for idle.