Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   DIY Turbo Discussion (https://www.miataturbo.net/diy-turbo-discussion-14/)
-   -   Running 'lean' in boost. (https://www.miataturbo.net/diy-turbo-discussion-14/running-lean-boost-65567/)

_spyder 05-02-2012 12:35 AM

Running 'lean' in boost.
 
My boosted '96 has been ripped apart and put together numerous times over the past year. I've been battling a 'lean' issue in boost and idle ever since. It idles a little rough and pretty lean. In cruise and on the throttle, it's fine. The AFR's will go down to mid 10's and 11's but as soon as I hit full boost, it creeps back up to 14+. Yes, that's dangerous, I'm aware. I've been beating on it expecting it to blow up so I had an excuse to rebuild (I have a DD). It burns considerable oil. I bought the car turbo'd with a dyno tune on an AEM F/IC piggyback a few years back and the tune hasn't been touched since. I'm starting to think that maybe my wideband is reading a 'fake lean', I don't know. What are some things I can check?

Stuff I've done to it over the past year that I can think of off the top of my head:
Deleted emissions stuff
Wire tucked ----
New plugs (what should these be gapped at?)
New wideband sensor
New recirculating BOV
Rerouted and deleted vacuum lines

Could a leak in the intake piping cause this? Exhaust? Bad injectors? Failing pump? Bad BEGI AFPR? O2 sensor?

I'm getting so fed up that I just want to swap a used motor in, get rid of the BEGI AFPR, throw in some 550's, and a Megasquirt hoping that the problem will be solved... but that isn't exactly cheap. I could throw up a .CAL of my tune if anyone wants to look at it...

Faeflora 05-02-2012 12:57 AM

Wow. You are a destructive fukker. More dedtructive thsn mr. Good job

U prob have burned all your exhaust valves an yor motor now has auto sdjusted and has shiite compression. Who cares though right? Yay now your motor is invulneravle to detonation so it is time to run all of it. I would unhook the wastegste now.

Yes you either have leak in itake aftet maf or more likely

Fuel pump is crap
Fuel filtet is crap
I jextors is crap

I can not believe u did a wire tuck but fail on your motor so hard

Ok i am done i am ready for you to felate my cow

Faeflora 05-02-2012 12:58 AM

And no it is not a fake lean. U r gay too

18psi 05-02-2012 01:06 AM

lmao, I love the logic:
you're not getting enough fuel, so replace everything BESIDES the fuel system components:laugh:

Faeflora 05-02-2012 01:10 AM

I am proud of op for making sincere dedicated effort in the pursuit of fail. Would rape.

_spyder 05-02-2012 01:40 AM

I'm aware that the motor is being beat on, compression can't be great, and the valves probably hate me. That's beside the point.

Fuel pump was replaced by PO with a Walbro unit that makes very loud ringing noise. I just replaced the fuel filter. Injectors haven't shown any signs of failure. The PO gave me two extra 305 green tops, maybe I'll try swapping those in by magically picking two lucky ones.

18psi 05-02-2012 01:51 AM

yes. run completely different sized/mis-matched injectors. should solve all your problems.
also lean it out a little more, you'll probably get great gas mileage.

also route the exhaust into the interior.

_spyder 05-02-2012 01:57 AM


Originally Posted by 18psi (Post 872652)
yes. run completely different sized/mis-matched injectors. should solve all your problems.
also lean it out a little more, you'll probably get great gas mileage.

also route the exhaust into the interior.

I've already got 305's in there, there are two spares.

Believe it or not, I'm not a complete moron.

fwMiata 05-02-2012 01:58 AM

what boost are you running?
probable that you are just exceeding your fueling.

adamvanxxx 05-02-2012 02:00 AM

I was going to say what is the duty of the injecshizz. But you don't have MS, so if the tune hasn't been touched maybe it is just a ---- tune.

_spyder 05-02-2012 02:01 AM


Originally Posted by fwMiata (Post 872657)
what boost are you running?
probable that you are just exceeding your fueling.

10 PSI with the 305's and BEGI AFPR. It ran good with 10-11 AFRs at full boost in WOT. Tried turning it down to 8 PSI, didn't help.

_spyder 05-02-2012 02:02 AM


Originally Posted by adamvanxxx (Post 872658)
I was going to say what is the duty of the injecshizz. But you don't have MS, so if the tune hasn't been touched maybe it is just a ---- tune.

I don't know how or why a tune would go bad though...

If anyone wants to look at a .CAL file from the F/IC, let me know and I can try to get one on here this weekend.

18psi 05-02-2012 02:05 AM


Originally Posted by _spyder (Post 872656)
I've already got 305's in there, there are two spares.

Believe it or not, I'm not a complete moron.

I'm going to take your lack of getting butthurt as a sign of promise and treat you seriously:

You know how when you're cooking something, lets say soup, and you start off with crappy ingredients and it tastes like vomit, and you keep adding salt and pepper, and water, and more salt, and more pepper, and more potatoes, and meat, and other crap, and it just gets bigger and bigger and more complex but still tastes like vomit?

Yeah, this is kinda like that.

Start over. Seriously. Do it. If you don't have money to do so, just sell off all the go-fast bits, refresh the motor, and enjoy a trouble free stock car, but don't just keep chucking crap parts into an already overflowing with crap parts car trying to get it to be nice, it won't happen.

Your choice.

_spyder 05-02-2012 02:09 AM


Originally Posted by 18psi (Post 872663)
I'm going to take your lack of getting butthurt as a sign of promise and treat you seriously:

You know how when you're cooking something, lets say soup, and you start off with crappy ingredients and it tastes like vomit, and you keep adding salt and pepper, and water, and more salt, and more pepper, and more potatoes, and meat, and other crap, and it just gets bigger and bigger and more complex but still tastes like vomit?

Yeah, this is kinda like that.

Start over. Seriously. Do it. If you don't have money to do so, just sell off all the go-fast bits, refresh the motor, and enjoy a trouble free stock car, but don't just keep chucking crap parts into an already overflowing with crap parts car trying to get it to be nice, it won't happen.

Your choice.

I've got a reliable DD, that's why I'm not shitting bricks right now. Otherwise I would probably do just as you suggest.

My original plan was go MS with 550's and ditch the bandaids/RR fuel crap, but I wanna find out why this is happening first. Then rebuild the head/motor if need be.

I don't know anywhere close to everything when it comes to boost, but I've come a long way and I'm willing to learn. It doesn't help that none of my friends or anyone else around here wants to touch MS. I hate this AEM crap that people charge up the ass for tuning. Miata or Miata knowledge is very rare around here.

bmxfuel007 05-02-2012 04:24 AM

shoulda gone with your original plan. wouldn't have this problem. you'd probably have other problems though :P

skidude 05-02-2012 07:27 AM

I'm with 18psi. Ditch the bandaids and put in a proper ECU, tune, profit.

Preluding 05-02-2012 07:52 AM

You say your pump sounds like its dog ----... well...it probably is....they don't last forever

adamvanxxx 05-02-2012 10:21 AM

Buy MS and tune.

If you can't figure it out from this website then you fail. There are so many MSQs posted, just take one and work with it. Chances are there will be one with your exact setup.

hornetball 05-02-2012 11:16 AM

Trying to figure out why bandaids aren't working before getting proper engine management is a true waste of time.

Also, Fae wants sex.

_spyder 05-02-2012 01:57 PM


Originally Posted by skidude (Post 872689)
I'm with 18psi. Ditch the bandaids and put in a proper ECU, tune, profit.

That's the plan further down the line when I have more spare cash, but in the mean time I want to figure out what's causing this. I don't know what or where else to check. I would hate to swap in an MS and 550's if that's not where the problem is.


Originally Posted by Preluding (Post 872694)
You say your pump sounds like its dog ----... well...it probably is....they don't last forever

How can I test a bad pump? This thing is really high pitched, but it always has been. Kinda assumed that aftermarket units were louder.


Originally Posted by adamvanxxx (Post 872742)
Buy MS and tune.

If you can't figure it out from this website then you fail. There are so many MSQs posted, just take one and work with it. Chances are there will be one with your exact setup.

I'd love to find one, do people post these in the MS section? I'd start browsing for when I go MS in a month or two.


Originally Posted by hornetball (Post 872769)
Trying to figure out why bandaids aren't working before getting proper engine management is a true waste of time.

Also, Fae wants sex.

But they were working great at one point, I just wanna find the culprit.

Also, Fae can have sex if he fixes my car. Not sure who he's gonna have sex with, but I'll find someone.


All times are GMT -4. The time now is 10:38 PM.


© 2024 MH Sub I, LLC dba Internet Brands