I depend on my AEM wide band for situations like this thankfully, but I cannot figure out why I am running so lean now on the top end 15-17!

I just installed my kit two weeks ago, everything working great, but after a day or two I would notice my afr's after vtec inch a little higher around 13.3 or so between 7000-8000 and then drop back to 12.5 or so at 9k. I just figured it was some more fine tuning I needed to do or it was a bit colder that day, so i just screwed in my fpr a bit till it was right, well it seemed like I was doing this just about everytime I got in the car to make my afr's safe, pretty soon I relized that I am maxed out on the fpr with no more adjustment today.

Today I started out ok with my AFR's and then went for my last bit on my fpr, after driving for a bit I noticed that my afr's are now running into the 15-17 in vtec and run rich below vtec, so it seems to be boost related in vtec. I use a vafc to lean out the bottom end, to remove this from the possible sorce I disconnected the vafc and still the same issue, so its something mechanical I would think?

What I need is some ideas as to what would be making my afr's continue to work themsefs lean and now so high to where it cannot be driven into vtec anymore without meltdown? I looked over all the fittings and hoses and did not hear or see anything that would make me think I have a leak somewhere, no fuel smell, nothing stood out to me. If there were a boost leak it would run rich I emagine. My afr's tell me I am running very lean and so does the fact that my power dropped off in reflection to this so i know something is up. Any ideas guys? This is my daily driver and I am planning a long trip this weekend.

Also to add, I had Honda dealer install the Walboro 255 fuel pump.

Thanks so much for your help!

 

it sounds like the ECU is relearning things the wrong way every time you drive your car. i would suggest checking the wiring of your ESM. or are you using something else instead?

do you have a fuel pressure gauge, by the way? what is it reporting? has your boost changed at all?

 

I am running factory ecu with esm. I have no fuel pressure gauge unfortunetly. Didn't think it was as imprtant as the boost and afr. Maybe I should get one. Thanks for the suggestions.

Would I get a check engine light if somthing was wrong with the esm hookup? I know I didn't have one wire connection very good when I first installed and the cel came on, it wouldn't idle durring this time. But after fixing that it ran great and still does below vtec so i don't understand. The boost seems to be ok at about 5 where it always has been, but my last romp was a little low at 4.5, I stopped hitting it after the afr's started to get scary so i don't know if boost is still good, it seems to be with no apperent leaks anywhere, i checked all the fittings when I got home tonight. Any other ideas?

 

Yeah, I would check the ESM wiring... Don't boost until you pretty sure you've figured it out. Back it off if you see AFR's climb into 13's...try again.

Good luck!

 

yes, i'm pretty sure you would either get CEL or the car would put itself into limp mode if the ESM was wired incorrectly. since you're good on both accounts it would seem your ESM isn't the culprit. still, recheck your connections anyway - you never know.

the next thing i would go after is the fuel system. how many miles are there on your car? i would consider yanking your injectors and having them tested and cleaned. some people have reported having problems with walbro fuel pumps as of late, but i have been personally using them for years and have never experienced any issues.

maybe you can check your FMU spring - it could possibly be old and worn out. did you buy your kit new or used? if it's used you likely didn't receive any extra springs for your FMU - i know comptech offers different sized springs. maybe you have the wrong one for your car, but i doubt it. in either case, i would bet its the FMU if the ESM wiring checks out. the FMU is a rising rate regulator, which means basically that it will add more fuel as vacuum pressure decreases (i think im wording this correctly), rather than across the whole spectrum all the time, which would net you some pretty crappy gas mileage. it seems your FMU isn't 'rising up to the task.' (i know - corny!). be sure to check the vacuum line that connects to the FMU and zip tie it. while you're at it, check the send line as well.

i'm sure this is aggrivating but at least you went the safe route and got a wideband! by the way, where did you have your afr sensor welded in? for the extra 30 bucks i would recommend grabbing a fuel pressure gauge - they are easy to install and worth every penny. come to think of it, i really should grab one too...

keep us updated!

 

Any idea which wire would likely control this aspect of the afr's? A stretch I know

 

as for wiring for the ESM, you can email comptech for the original PDF files associated with the supercahrger kit, as well as the ESM. it will show you where to wire it in.

 

Ditch the ESM and get the Synapse Missing Link. I'd also recommend resetting your ECU. It seems it has learned all kinds of bad data.

 

The kit was used and was supose to have less then 10k on it, it seemed to be in pretty good shape so i would likely concur with this.

My injectors were just cleaned and flow benched a few months ago- all good there

FMU? do you mean my FPR? So if I crack it open should I be able to tell if the spring is working? It looks like its just a half a dozen allen bolts holding it together, is there anything I need to know before I bust into it and starting looking at things? Since I had it cranked down today (all the way) to compinsate for progressivey running lean, is it possible that the spring is stuck or broken? i did not hear or feel it break however, if I could tell or not I don't know. This would still not really explain the two weeks before hand of good running but the progressive leaning that began the last week or so. Today was the big shift from 13's to 16's

Ok on the guage, I have seen most peopl run them off the fuel rail or somthing there in line with the fuel line? Since I go lean mostly in boost, how would I see whats going on with the guage? Seems like I would need refrence real time in with the rest of my guages right? Or should I know if I have an issue just at idle pressure or revving under the hood?

 

Well from my days of tournament paintball I remember the air regulators actually will start to loose pressure if you go too far. So you were probably turning it up to a point then It started turning down.

Did you check all your vacuum hoses??