2011 rich condition, AFR seems good

I

IssaSlowCar

Greenie N00B Member
Hey y'all, as the title says I've been fighting with a bit of a rich condition for a while and I'm running out of ideas before just getting re-tuned. My LTFT at idle will range from -3 to -14, going closer to -3 whenever the A/C compressor is on then richer again when it disengages. AFRs appear to be good hanging around 14.5-14.8 at idle. I've also noticed that the PO had set the EBCS up with ports on the boost reference and wastegate at 1/4" fittings whereas all the other fittings are 3/16 standard. I have new clamps on all the hoses to verify they seal, boost appears to be fine as I'm hitting target and holding pressure as expected. Fuel economy I'm getting approx 190-220 miles to a tank of mixed driving with little boost being applied throughout the tank. Closer to 170 miles if I'm ripping it. Attached is logs at idle, light acceleration and 3rd gear WOT. I also get random high knock readings but I'm tackling one issue at a time.

https://datazap.me/u/issaslowcar/running-rich-issue?log=2&data=6-8-17-18-19-22-23


Year/Make/Model: 2011 speed3
Mileage: 114,000
Location: NJ
Concern: Rich condition mostly at idle
DTC's: P0172
Modifications: Manley rods, CPE stage 2 pistons, CPE exhaust manifold, GTX3076R, Tial 44mm wastegate with 14lb spring, Grimmspeed EBCS, VTCS delete, ported intake manifold, upgraded HPFP internals, HTP 3.5" intake, HKS SSQV, Cobb catted downpipe, Ultimate racing catback and FMIC kit, EGR delete, balance shaft delete, JBR catch can.
ECU/Tuning Software: Accessport v3
Tuner: Freektune
Is the concern intermittent? No
Can you duplicate the concern? Yes
Recent Repairs: New NGK LTR7IX-11 gapped at .024-.025, Upstream o2 sensor for unrelated issue, re-secured EBCS hoses. Compression tested while replacing plugs for good measure and found 185-190psi across the board.
Correction:
 
What has Freektune said about your rich issue and have you contacted him about it?

What about your MAF sensor and injectors? Have you had the injectors cleaned at all?

Have you changed the oil recently? If there was a rich condition that you repaired but didn't change the oil afterwards it's possible that the rich condition is due to oil being diluted by fuel.

How long have the internals been in the HPFP and were all the seals replaced at that time?
 
Oil change was performed 3 weeks ago, I've gone back and forth with justin a bit and he's suggesting re-doing the tune which I planned to regardless, I just want to get everything running properly beforehand plus I want to change the exhaust setup a bit and go full corksport. Manifolds and 3.5" exhaust. At the same time I'll be going PI which is why I want to sort out the small issues first in case I might be overlooking something. Injectors were last service approx 40k miles ago when the motor was built, cleaned the MAF approx 2 years ago which was at 103k miles. I'm not sure how long it's been since the HPFP was rebuilt as I bought the car with the mods already done and ended up running into the original owner who had the motor built and done all the mods back then. Motor was built at approx 70k miles. It just throws me off cause when I drive my LTFT isn't terribly negative, usually hanging close between 0 and -3. It rarely goes positive though. This is also why I've been wanting to find a factory repair manual with wiring diagrams so I can properly give the harness a look over in case it's a wiring issue. I know the car at one point had 6th port injection but that was since removed and I'm not sure where they tapped into the system/how they did it so I plan to either check it all or nut up and order a new OE harness from Mazda to guarantee everything is untouched and fresh and routed properly.
 
If your LTFT is mostly rich at idle it could be a fuel pressure issue or leaking injector issue.

During load situations it's easier for the engine to compensate for the rich condition than at idle where you're just burning gas.

Send your injectors out and have them flowed/cleaned by a reputable company. At least you'll get a good answer as to their condition and have them returned flowing pretty much even.

If that doesn't correct the rich condition then start doing the classic spark plug inspection diagnostic to try and isolate a cylinder that could be causing it. See which plug looks to be the most fouled. Not the most accurate test but can get you in the right direction.
 
Yeah I've thought about it a bit and might pick up a second set of injectors and send my current set out, just can't quite have the car down until spring when I can ride to work most days. So much to do with so little time to have it down.
 
You must log in or register to reply here.
Back
Top