yeah doing the walbro will richen up your AFR a bit

 

Walbro is installed and I will do some logging in a day or two. If my IDC's are still high, would injectors be needed next or just getting the tune correct be enough? I'm guessing I will need to lean out the map. I will see after some logging how it looks.

 

Adding the walbro wont change IDC's - but if your lucky your AFR will richen up a lot so you can tune that out, thus reducing your IDC's.

Put up a WB log if you want

 

So you have a TBE with O2 housing, air filter and MBC @22psi peak and you're exceeding the VIII fuel system? Usually you are in the red zone but not maxing it out, especially at 22psi. Granted thats not a rule, just an observation.

 

It did seem early to me also but the logs seem to support it. Stock pump may have been on the way out.... I will see how the logs look. No matter, it was cheap and an easy install. I would like to do cams next, perhaps I will have to do injectors also.

 

I had a 03 Evo hit over 110% IDC's last week with just a TBE with *stock* cat, open filter, fmic and ecu-boost holding 18psi.

Swapped in a walboro and all is good now.

The 03-04 pumps aren't so hot.

 

I agree. I haven't logged yet but watching my WBO2, where I was reaching an AFR of 12.5 over 5000 RPM, I'm now dropping down in the 10's with zero changes other than the Walbro. time for me to start logging and tuning. I will post a screenshot of a log before any changes are made as a comparo.

 

Why dont you log IPW with evoscan and find out how much injector you have left?

 

yea this 03 did pretty much the same thing, swapped the walboro in and the AFR richened up a little over 1 full point.

 

good on ya, *phew* Evo saved

 

To me this makes no sense. So you are saying that the ECU somehow knew that fuel flow was low in OPEN loop and increased the SET fuel cell parameters to counteract the lack of flow??

The IDC's would always be the same depending on the fuel map during WOT open loop runs. The thing that WOULD change from the lack of fuel flow are the AFR and EGT's...and crazy knock.

Unless it was tuned with such IDC's of course. In that case, tisk tisk on the tuner,lol.

 

no i think he means that with the original pump he needed very high IDC's to get the AFR's right. However after putting a walbro and retuning the IDC's dropped for the same AFR's.

 

I think you are reading into it too much.

At 18psi (holding) the car would max out the fuel system. I had to run it very rich (in the fuel map) to even get it close to what my desired AFR was up top. This resulted in 110% IDC's and I still couldn't get the AFR I wanted.

Swapped the walboro in, the first pull with the tune above instantly was over 1 point richer, after tuning I could hold 20psi with no fueling issues, I could achieve the AFR I wanted and the IDC where now 10-15% lower.

Obviously something was going on with the fuel delivery with the pump and the injectors where working over time trying to support the fuel demands.

 

Here is the after. You can see that with the same map, the AFR's go as low as the 9's in one area. After I adjust fuel, my IDC's should be reasonable.
After Walbro Install

 

One other question. I noticed now that in the RPM range where I was lean (now very rich) 5000k RPM+, it feels different and there is an occational miss or hesitation. I'm sure it's the fuel richness causing it and I can tune it out with some adjustment, just wanted to get an opinion. Thanks.