Lexus AFM & 550s issues...

[MA70_Powa]

Hey guys,

My car has been sitting at the mechanic's for the past week trying to get it running. As I pointed out in an older thread I had about that issue, it now runs
But. I have a different problem...

I decided to do the lex afm/550s upgrade now while it was there, but this is where Im having problems. EDIT: With the lex afm on there it runs Really lean, and bogs when you touch the accelerator.

If they use the stock afm, then it runs pig rich, but runs fine and doesn't bog.

Now, I haven't been there yet to hear the car for myself (will do it today hopefully) but from what they tell me, it's really odd.
My mods:
Brand new walbro
RC 550s
LEXUS AFM
3" DDP
Hypergear 43i turbo
J-tube bypassed
2.5" IC Piping to big-ish IC
Turbosmart recirculating BOV

Now, they've tried swapping the electronics from the stock afm to the lexus one but there's no difference. So that means both electronics work.
As far as I know, there are no error codes.

They are using their own wideband, as I don't have mine installed yet. I also don't have an AFPR.

Anything else I should get them to try?

I do have an S-AFC sitting here but I'm gonna be rather poor paying for what theyve done so far, so if I can get the car back without having to pay for tuning just yet I'd rather do that and then wait for next payday

Sorry about the lengthy post. Any help you guys can give me would be great!

 

[hvyman]

adjust the screw out some to get more air.

 

[Sprmcy]

1)Get a Piggyback system. This will help regulate your Fuel/Air ratio. HKS FCON will work fine
2)Have the ECU tuned. when running bigger injectors you always want the ECU to be tuned

 

[MA70_Powa]

ACK!
OK I just went there to have a listen to the car, and talked to them about it while I was there.

Turns out it's actually running mega LEAN, not rich, with the lexus afm on there. There was a bit of mis-information earlier. It's now behaving exactly like it was when I was having my previous problem (when my fuel pump was dying).

So that changes everything...

However, I did just drop off the SAFC to them to install and mess around with, so hopefully that can fix it.

Now that it'll have the SAFC, do I really need an AFPR? Bear in mind I won't be going over 350rwhp. It's $300 I'd rather not spend If I don't have to hehe

 

[gaboonviper85]

The lex/550 mod isn't perfect...it's close but not exact!

Your rich issue is cause you don't have an aftermarket fuel pressure regulator as well as you probably don't have the "J" tube bypassed! The jtube is very restrictive to the high flow 255 walb and will cause too much fuel pressure which in turn will make you run rich!

Before you just up and install performance parts it's best to do research on it....when installing one mod generally means you'll have to mid something else within the system to support the initial mod.....it's a chain and everything is linked together....fallow the order!

The chain for the lex mod is:

1. Lex afm housing
2. Afpr
3. 550cc injectors
4. Piggyback of sorts
5. High flow fuel pump of your choice aslong as it flows enough
6. Jtube bypass
7. 12v fuel pump mod "not required but makes life easier"
8. Wideband
9. Tune

good luck and complete the system before trying to run.

 

[NewWestSupras]

I'd get the afpr if I were you. I'm running basically the same mods with the only difference being a Denso MKIV fp. My af ratio numbers are pretty good (in the low 12's under boost). I'm not sure what "tuning" you can do with a stock ecu, as per Sprmcy, but I'd sure like to learn about that. (First I've heard of that approach, unless he's specifically talking about the ecu in conjunction with a piggyback). Anyways, running lean is a bad idea, so an adjustable fpr is the wtg with those mods you already have. gl. OOps, GaboonViper beat me to it.

 

[MA70_Powa]

gaboonviper: I do have the j-tube bypassed
And it's running lean not rich, but you probably read it before I posted the second time and edited my first post
I'm looking into afpr's at the mo that i can get here, because getting one from the US will take too long

 

[wiseco7mgt]

Oh an aussie, just get one from driftmotion, he sells the full kit which makes life easy and freight is quick( less than a week for me). The aeromotive is very good value for money, stay away from cheap e-bay knock offs, fuel leaks under the bonnet aren't a good thing.
A good starting point with vac line off the FPR is around 33-37 psi and go from there useing your wideband. Keep an eye on your VF's as you tune and try to keep the ecu happy, that will make things a little easier for you.

 

[SUPERIUM]

Powa, have you driven the car under full boost yet? The cars supposed to be lean just at idle and normal driving habits. While staying out of boost your ratios should be around 14.6-16.0.

 

[MA70_Powa]

I suspect it's having the same issues as I had before, as from what I saw when I went there it was behaving the same as in the past. Basically, off boost it runs like crap (and really lean) and bogs when you touch the accellerator - it's really hard to get it going anywhere.
If you manage to get it moving enough to get into boost, then it goes fine. At least, it did when my fuel pump was dying. Currently they haven't driven it out of the driveway of their workshop because of how it's behaving.

Could there be a problem with my fuel pump relay mebbe? so that when its only on 9v its not functioning properly?


Also, with the AFPR, I could order the driftmotion one, which won't get here til mid next week, or I can go down the road and get a turbosmart one today/tomorrow. The only problem with the turbosmart one is the fuel rail adapters they have. One suits the 1jzgte/3sgte fuel rail and the other suits the 2jzgte... anyone know if either of these will fit?

 

[isnms]

Have you drilled out the access to the bypass screw on the lex afm housing?
Screw that screw all the way in.

Check your VF
You'll be fine with 3.75V at idle. Check your cruising should be 2.5V
Don't worry if your 3.75 is 3.25 or your 2.5 is 2.25 just look for that range. There are five.
Check out the url's at the top of the image, they have good information.

 

[MA70_Powa]

Cheers for the Vf info, it's something I hadn't seen before.
I'll pass it on.
Slight problem with checking the cruise one tho, as it has to actually be able to move properly first

 

[MA70_Powa]

Mini update - When I talked to them yesterday briefly they told me my fuel pressure was 38-40 psi (I assume that's vac off, forgot to ask lol) so that should be fine?
In any case, I've ordered the Aeromotive AFPR kit from driftmotion - but I want my car running before it arrives lol...

 

[wiseco7mgt]

You won't be dissapointed, buying a kit that has all the bits is just magic.
hows is the tune coming along?

 

[MA70_Powa]

Tune was going good when I talked to them, BUT.... Their wideband died! they've ordered one express post so theyll have it Monday, meaning I get my car Monday (unless something else goes wrong...) Finally lol. And hopefully my issues will be resolved!

 

[MA70_Powa]

YAY!
I got my car back!

Picked it up after work yesterday
Runs great now - they tuned it for 11-12 AFRs with the SAFC, and all is going well so far - except it did stall on me about 4 times and has a slight hesitation when you push the accelerator - so I'm gonna check my spark plugs and see if I have any air leaks.

Oh, and my compressor surge is back...

So for now all is (relatively) good, thanks for the help so far everyone!
The AFPR should be here any day now so hopefully I won't have any issues installing it. Although, if I do, won't it throw my tune off, since I'll be changing fuel pressure? Mebbe I should wait until I get my WB installed?

 

[wiseco7mgt]

Yes mate it will throw off the tune, personally would wait until the wideband arrives.Then it's all pretty easy. Good to hear your back driving again.!