wbo2 installed... scary afr's - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Prefabbed Turbo Kits A place to discuss prefabricated turbo kits on the market
Sponsored by:
Sponsored by:

Reply
 
 
 
LinkBack Thread Tools
Old 05-20-2008, 09:14 PM   #1
Elite Member
Thread Starter
iTrader: (13)
 
Join Date: Dec 2006
Location: Taos, New mexico
Posts: 5,702
Total Cats: 237
Default wbo2 installed... scary afr's

Ok so I've been running this setup around 5-6psi for a while.. and my motor still seems to be very healthy(doesnt smoke).. so i figured my afrs would be alright..

I wish.. idling they hang out around 14.5ish and will occasionally lean and rich out a little if it idles for long enough. On the road When i get on it they are around 14 at say 1k rpm, they richen out to a nice 11.5 or so, then lean out to 12... and right at 4k rpm they hit 14's again and hold to redline. =(.

So I'm going to guess... dying fuel pump? Most likely I'm thinking, as it is the original one i believe(170k miles). I will test it tomarrow if i can source a gauge.

What do you guys think?



Setup in sig.

Last edited by Fireindc; 05-20-2008 at 09:33 PM.
Fireindc is offline   Reply With Quote
Old 05-20-2008, 09:35 PM   #2
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,872
Total Cats: 1,790
Default

it could be the FP, you'd need to put a fuel pressure gauge on the feed line to see what's going on in boost.
Braineack is offline   Reply With Quote
Old 05-20-2008, 10:44 PM   #3
Elite Member
Thread Starter
iTrader: (13)
 
Join Date: Dec 2006
Location: Taos, New mexico
Posts: 5,702
Total Cats: 237
Default

Quote:
Originally Posted by Braineack View Post
You need to verify the condition of your pump. Looks like it can barely supply fuel. It could be working, the filter could be a restriction, or your plumbing could be wrong.

First off, verify your FMU is plumbed correctly. The fuel line from the OEM FPR should be connected to the offset fitting on the FMU. The center fitting shoulb be connected back into the return hardline. The line from the FEED line to the front of the fuel rail should not have been touched.

If this is correct then replace you fuel filter and buy a fuel pressure gauge and test your pump.

You'll need:

1 - Fuel Pressure Gauge (on the cheap at any local hydraulics store, try to get one that can read to at least 125psi)
1 - 5/16" brass tee
1 - 1/8" NPT to 5/16" fitting (for the gauge, shop shoudl be able to help)
5' - 5/16" fuel injection hose
5 - Screw clamps

To install:

Cut about 1' off the hose. Clamp that section to the brass tee. Clamp the 4' section to the tee as well. clamp the gauge on that 4' section.

Remove your fuel inlet hose from the hardline (otherside connects to the front of the fuel rail) and connect that to the tee. Then connect the 1' section of hose to the hard line.

To Test The Pump:

Start the car. Idle should be 35-36psi. Remove the vacuum line from the OEM FPR on the fuel rail. (Kink the vacuum hose so the car doesn't die). Idle should be 48-50psi.

Stop the car. Jump GND & F/P in the diagnostics box. Turn the car to ON, but don't start it. This will run the fuel pump. wrap cloth around the return line and use a vice grips or something similar and clamp down on the hose. This will increase the fuel in the rail. Verify 75-85psi.

If your pump cannot supply this amount then it may be in need of replacement.

To Test The FMU:

Ignition to ON. Keep the GND & F/P jumped. Run 5psi of air from an air compressor into your FMU vacuum line. Verify the fuel pressure increases to the max pump output.

hope this helps. can you send those .drf files this way?
^^ Is what i plan to do tomarrow. (gotta love search)

Ive never noticed any knock ever, and Ive kept my eyes(and ears) open for it since i installed the kit. Do you guys think i did any damage? I do smell gas in the oil.. but I'm pretty sure that was because my o2 was out for a while(i just replaced it today, and it runs and idles MUCH MUCH better, and no longer smells like a carburated car while idling.). But the motor does not smoke at all...

Also the wbo2 is installed about 2 inches away from the outlet of the exhaust(open downpipe) Ive heard of air going back in and leaning out the sensor, but im guessing this wouldnt be the case at 4k+rpms.
Fireindc is offline   Reply With Quote
Old 05-20-2008, 10:54 PM   #4
Tour de Franzia
iTrader: (6)
 
hustler's Avatar
 
Join Date: Jun 2006
Location: Republic of Dallas
Posts: 29,114
Total Cats: 351
Default

and 11.5 is too fat according to the power players on here. There is no real reason to go fatter than 12.1 or so sub 350whp.
hustler is offline   Reply With Quote
Old 05-20-2008, 10:58 PM   #5
Elite Member
Thread Starter
iTrader: (13)
 
Join Date: Dec 2006
Location: Taos, New mexico
Posts: 5,702
Total Cats: 237
Default

Yeah, from what ive read im shooting for between 12-13 afrs.

I want to get this piggyback setup running decent for the time being, as i need to buy other stuff before megasquirt(which is definitely in my future).
Fireindc is offline   Reply With Quote
Old 05-20-2008, 11:47 PM   #6
Elite Member
iTrader: (14)
 
Join Date: Mar 2006
Location: Edmonton, AB
Posts: 4,921
Total Cats: 0
Default

My vote is weak fuel pump.
jayc72 is offline   Reply With Quote
Old 05-21-2008, 12:24 AM   #7
Elite Member
iTrader: (3)
 
Mach929's Avatar
 
Join Date: Oct 2004
Location: lansdale PA
Posts: 2,500
Total Cats: 0
Default

um i see nothing adding extra fuel in for boost in your setup
Mach929 is offline   Reply With Quote
Old 05-21-2008, 01:00 AM   #8
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,364
Total Cats: 1,325
Default

Quote:
Originally Posted by hustler View Post
and 11.5 is too fat according to the power players on here. There is no real reason to go fatter than 12.1 or so sub 350whp.
Ben made more power when he added fuel. My car pings leaner than 12.2.
Savington is online now   Reply With Quote
Old 05-21-2008, 01:08 AM   #9
Elite Member
Thread Starter
iTrader: (13)
 
Join Date: Dec 2006
Location: Taos, New mexico
Posts: 5,702
Total Cats: 237
Default

Quote:
Originally Posted by Mach929 View Post
um i see nothing adding extra fuel in for boost in your setup
Yea, sorry im running the vortec fmu w/ stock Greddy kit disk (12:1)?
Fireindc is offline   Reply With Quote
Old 05-21-2008, 01:26 AM   #10
Antisaint
iTrader: (17)
 
Vashthestampede's Avatar
 
Join Date: Feb 2007
Location: Danbury, CT
Posts: 4,659
Total Cats: 54
Default

For the record, I was having some fuel issues that went away the same day I replaced my stock fuel pump with a Walbro. Always worth it to replace things like that when they are getting close to 20 years old! And don't forget the filter too!

Vash-
Vashthestampede is offline   Reply With Quote
Old 05-21-2008, 05:11 AM   #11
Elite Member
iTrader: (11)
 
Join Date: Jun 2007
Location: Overland Park, Kansas
Posts: 5,382
Total Cats: 43
Default

Quote:
Originally Posted by hustler View Post
and 11.5 is too fat according to the power players on here. There is no real reason to go fatter than 12.1 or so sub 350whp.
Jesus.. I'm running around 11.5 at WOT on my N/A car... Kept tuning and tuning and tuning and tuning.. The thing is a fuel hungry *****, but it runs pretty damn good for N/A..
elesjuan is offline   Reply With Quote
Old 05-21-2008, 09:02 AM   #12
Ben
Supporting Vendor
iTrader: (33)
 
Ben's Avatar
 
Join Date: Jul 2006
Location: atlanta-ish
Posts: 12,689
Total Cats: 99
Default

Quote:
Originally Posted by Fireindc View Post
Yea, sorry im running the vortec fmu w/ stock Greddy kit disk (12:1)?
12:1 disc will deadhead the fuel pump. I'd be curious to know if a 8:1 or so would give you more fuel up top.
Ben is offline   Reply With Quote
Old 05-21-2008, 12:39 PM   #13
FHS
Senior Member
iTrader: (2)
 
Join Date: Oct 2004
Location: Los Angeles, Ca.
Posts: 502
Total Cats: 0
Default

If it's the typical GReddy, he's running lean right about where the GReddy spools to max boost. The 12:1 and FP are dumping plenty of fuel as boost rises. An 8:1 disc might actually help alleviate the rich condition spooling up, but it seems like the FP will still crap out if it can't provide enough pressure at max boost?
FHS is offline   Reply With Quote
Old 05-21-2008, 01:00 PM   #14
Supporting Vendor
iTrader: (3)
 
Join Date: Jul 2006
Location: San Diego
Posts: 2,863
Total Cats: 485
Default

I would agree that it's not the FPR. I'm currently at 7 psi and nowhere near 14:1. Granted, I'm using MS to control things, but it's running stock 1.6 injectors backed by the vortech fpr with the 12:1 disc, so if I can pull better A/Fs with another pound of boost that you you should be able to too unless your pump is shot.
-Ryan
ThePass is online now   Reply With Quote
Old 05-21-2008, 01:09 PM   #15
Elite Member
iTrader: (8)
 
Join Date: Sep 2006
Location: Severn, MD
Posts: 1,927
Total Cats: 5
Default

I've got an FP out of my NB if you want it. 30K miles on it. You'd need to cut the ends off your connector but the NB pump just uses ring terminals.

Obviously a Walbro is an option, but if you want to save some bucks...

Frank
fmowry is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
MS PNP requires reading and following directions??? satisfied MEGAsquirt 141 10-06-2015 11:44 AM
why is my car running like pewp? (tune/datalog) itsMikey MSPNP 3 09-28-2015 07:40 AM
TPS based AFR map for better mileage (?) elior77 MEGAsquirt 30 09-23-2015 07:38 PM
AFR Not showing anything eunosgippa MEGAsquirt 0 09-09-2015 06:19 PM
ME221 Now has Autotune and Long Term Fuel Trim Tables Motorsport-Electronics ECUs and Tuning 0 09-05-2015 09:02 AM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 05:21 PM.