Autotechnica

Hey guys,

I've just had a Needswings ASP 178mm crank pulley with the NW PSK put in as well as a Eurocharged ECU remap. I seem to have a pretty bad lean condition above 5000RPM. I've read about this problem with a member who had an E55K, but haven't read anything on the C32's. His issue turned out to be the fuel pump. However, without a wideband AFR to monitor your air fuel ratios, you'd probably never know anything was wrong since the car runs fine. I get 11.7-12.2AFR's @ WOT to about 5000RPM. Once I get past the 5000-5500RPM range, my AFR's lean out significantly to 13, 14 then 15! That's way too lean and beyond the safe zone. From the information I've gathered on this forum, everyone says no fuel upgrades (injectors, pump, etc) are required. Could my issue be a failing fuel pump/sender? The reason I would like some opinions is because the pump/sender aren't cheap. They're around $600. Since I just replaced my water pump, my wallet is hurting. At the same time, I don't feel safe hammering it around with this issue. My car has ~120,000kms (~70,000 miles). I'm not sure if the fuel pump is regular maintenance in these cars. Any help would be greatly appreciated. BTW, using an AEM UEGO wideband.

Thanks,

Bry

Gramma_Benz

First thing to check is your fuel filter...

91RS

Off topic, but what are you using to check your AFR?

splinter

Good catch. Wise to keep your boot out of it while running those dangerously lean AFRs.
Is this a recent occurrence, or has it been manifesting gradually over time?

My experience has been that the C32’s fuel pump works perfectly right up until the moment it fails.
Suggest first verifying yours is in fact receiving sufficient pressure to the fuel rail when it goes lean.

Specification is ~3.8 bar/55 psi. Assuming for the moment that the pump is up to snuff,
our returnless fuel circuit’s pressure is determined by the filter’s integral pressure regulator.
If yours hasn’t been replaced in a while, fitting a fresh OE Mahle-Knecht filter (PN 002 477 30 01) might be prudent.

Note winterized, oxygenated, ethyl alcohol and increased RVP RFG blends tend to inherently weaken mixture strength owing to reduced relative density.
The injectors’ programmed duty cycles -metering via volume- don’t necessarily account for those potential differences during WOT OL operation.

If the basics check out okay, perhaps a friendly chat with your tuner is in order.

FrankW

Keep out the red zone! Hope you get this figured out soon.

Fuel pump maybe?!

Autotechnica

Looks like I'll be replacing the fuel filter first then. If that doesn't solve the issue, I'll tap the fuel line with a fuel pressure gauge and throw the car on a dyno. Motor's have a tedency to blow when they're not running properly on the dyno. Probably due to increased load settings.

I'm definitely experiencing leaner AFR's due to the colder weather, but I cringe whenever I see anything leaner than low 12's @ WOT. I'm sure Jerry wouldn't tune for 14-15's.

Splinter, unfortunately, I've only very recently wired up the wideband, so I don't know if it was running lean when the car was stock. However, I had the eurocharged ECU when I had the stock pulley as well. It would breifly lean out to 13.1 or so. I imagine the problem was still there before, just that the 178mm pulley seems to have accentuated the problem.

91RS, using an AEM UEGO.

Thanks guys, will report back after I've done the fuel filter.

splinter

Any luck?

Autotechnica

I've picked up a Mahle fuel filter w/ internal regulator but have not installed it yet. I need to get on the ball and do it this weekend. I hate working in chilly temps.

Autotechnica

Update....

Just installed my fuel filter. Pretty easy job. Most time consuming part for me was just jacking up the car. The original clamps came off easily. Once you figure out where to pry, it's not difficult at all.

Bad news, still having the same problem. The fuel filter/regulator replacement did not cure it. I took the car for a run on the highway and decided to do my best at recording it on video. Perhaps Jerry from Eurocharged can shed some light on this problem. IMO, it's far too consistent to be fuel pump related. It leans out right before 6000RPM every single time. Uploading video now. Will post link when done.

I'm reading the RPM's out since I can't see my datalogger properly. I was in 3rd gear and didn't let off till it changed up to 4th gear. So you can see it runs lean for a moment, basically leans out right before 6000RPM till redline. It's enough to damage the motor, especially if I did a high speed pull in 4th gear.

BTW, what's the stock redline on these cars? I'm thinking it's possible that something wonky on the tune is making it run lean past the rev limiter since the eurocharged map has a raised limiter. Perhaps that section of redline is untuned? No idea, just thinking of different possibilities.

VIDEO BELOW...

http://www.youtube.com/watch?v=nYgchD9sXLE

splinter

No doubt that consistent lean spike is worrisome.

With the filter now checked off of the diagnostic flowchart, I’d suggest verifying sufficient volume (and its commensurate pressure) at the rail before contacting your tuner.
That my pump worked perfectly until it died is no guarantee yours is healthy. One member, TemjinX2, lost a C32 piston owing to a weak pump. No one here wants to see that happen with yours.

Of course if it is the tune, I’m certain Eurocharged has an appropriate workaround in its files.

loungn14

definitely check fuel pressure at the rail....thats the only time I have seen anything like that (regulator bad)

It would be odd for it to be the file, as we use the same file for hundreds of cars

Lenin

Autotechnica,
Can you post your log file from the DashDaq? I want to compare it to mine.

Autotechnica

Sure, what would you like me to log?

Autotechnica

Where's the best place to tap for a fuel pressure reading? Also, is there another fuel pressure regulator at the rail? If so, can I run something like an AEM adjustable fuel pressure regulator? I have one kicking around that I'm not using.

thanks.

Lenin

RPM, TP %, SparkAdv, Speed, MAP, AFR

Here is a link to a picture of a fitting and a place where to connect it for a fuel pressure reading. This is what I use. http://www.needswings.com/Fuel-press...psfitting.aspx PM me if you need more info.

Autotechnica

Any chance the gauge could be connected near the fuel pump so I could check fuel pressure while on the road? It would save me some dyno time/money.

thanks.

splinter

Any luck?

lizardjack

There is a dedicated port under front engine cover.

Autotechnica

Nothing yet. I finally got around to ordering the Zeitronix fuel pressure sender for my dashdaq. I have the fittings required to tap the fuel rail but I've just been too busy (lazy) to do it. I don't recall how to run the wires through the firewall. Can anyone help? My shop ran the wires through the firewall for my wideband install, but I wasn't paying attention when it was being done. Seems like every forced induced car I've owned had leaning issues when there weren't supposed to be any. I may just end up going back to the stock pulley. Better for reliability anyways.

thanks,

Bryan

320 dreamer

remove ecu and fish the wires thru the hole in the bottom to the interior.

gt4awd

When my pump was failing it ended up reaching a point of major power loss at higher RPM due to extremely lean conditions. I felt the vehicle progressively got slower over time as well. Just saying I don't believe the pumps all the sudden stop without prior loss of pressure as it fails.

gt4awd

There's also an opening through the side panel with interior fuse box by steering wheel. You have to poke through some foam it wasn't easy, but didn't have to remove ECU box.

boohooramblers

You might as well have all unknowns addressed if you are doing all this work for datalogging and sensors.

If you are doing all this work, why not send your ECU to Eurocharged just to check the remap file in the meantime?
Given their reputation, I'm sure they'd be happy to do that for you (of course, you pay for shipping, etc.).