Lately my fit's been hesitating when it hits 2500 rpm and 4-5k rpm (varies at the higher rpm range). It'll be going just fine, and then right at 2500, it "hiccups" as in, it stops accelerating, the engine feels like it's not being fed gas, and then it jumps back to life and keeps on going. Same thing happens between 4000 and 5000 rpm. It happens with moderate to full gas pedal depression.

If I really baby it, it doesn't happen. If I put it to the floor, happens every time. Seems to be hit and miss with everything in between. I've been watching the o2 loop on my scangaugeII, and it happens in open (which occurs with pedal to the floor) and closed loop (anything but pedal to the floor). Just before getting online, I was accelerating onto the freeway and it got stuck in open loop. I dunno what the deal was with that, but shutting the engine off (I know, dangerous) and starting it back up seemed to clear the issue.

Before I "rebooted" the engine, though, it started to hiccup repeatedly at 4k rpm, and my check engine light started flashing. After a few seconds, it went back to normal, and that's when I was stuck in open loop. Scangauge didn't catch any code though. I'm confuuuuuused.....

 

email KW. Never had the problem in the year that ive had it. Have you re-looked over the injector clips make sure everything is nice and connected?

 

Injector clips are good, fuel rail is still tight, in place, everything seems in order. Clamps on all the vacuum hoses are tight, can't find any leaks (even had a helpful stranger push on the gas a bit to see if i could hear/feel any leaks).

Left KW a voicemail and will email them shortly. Do you think resetting the ECU (neg. batt. terminal trick) and doing an engine idle re-learn might help? It has gotten very warm and humid lately, so I'll relay everything to Oscar at KW. Thanks for the inquiry, Chris

 

I had a similar issue on one of my home made turbo set-ups (old VW). It ended up being my injectors, if you have time give yours a check.

The tip of the plug was missing (not 100% sure how) on one of the injectors, and when I had over 80% throttle (~3+psi) I think the gap was way to big for it to arc properly.

 

man sorry to hear that. it has been crazy hot lately. my air temp has been in the 120-130's sometimes. the damn intake pipe is so close to the header. i think i am going to have to get it wrapped. i wonder if we are getting close to maxing out the stock injectors. my fit has been sluggish lately too. no hiccups that i have noticed though. check the clamps near the header. mine expanded because of the heat and caused a vacuum leak. this hapenned to rexxx too. i bought t-bolt clamps from jegs along with 195cc injectors from rc. i put the injectors in today and will install the clamps tomorrow morning. also put in 1 step colder plugs and the password jdm thermal IM gasket. it's crazy hot in the engine bay. maybe heatsoak is causing it. i've got to try and vent some air in there.

 

the hiccup could be any number of things, one main thing is if you checked all your vacumes and stuff you may have bad gas what grade are you running? and do you have a fule presure gauge to see how much fule you putting out or an FMU. ... see im just saying all that i know for turbo but im sure supercharger is just about the same when it comes to fuel managment.

oh and another thing i havent read up on this kit but are u running all stock injectors, fuel rail and pump or do thay supply you with all upgraded stuff. i know my buddy put a turbo on his car LOL and dident upgrade the fuel pump and he was having this problem(yes i know this is a supercharger but like i said im sure the fuel management runs the same).

 

Thanks to all for the suggestions. I reset the ECU, and it seems to have smoothed out for now. I'll see what happens once my car's relearned my driving habits. Could've been the higher temps, could still be the injectors, maybe too big of a gap on the plugs. Thanks to bmxracr and mrclean for the plug gap suggestion and 07_g_fit. All will be diagnosed after I get some rest. 1,000 miles of driving, two nights out at the bars, and not a whole lot of sleep this weekend really wear on ya.

Will update on this problem later. Also going to the dyno today and hopefully get some insight and face to face help on a/f management and monitoring (no system yet, just scangauge and the SC. Meneeds wideband o2 sensor-ation).

 

let us know how it goes my friend!

 

man that is crazy. i didnt' think that the charger would make us run so hot, i can only imagine what the turbo set ups are doing!

 

Looks like something fouled plugs 3 and 4 (the two on the driver side of the car). I'm thinking the bigger injectors might've caused it, as well as the thousand-mile trip I made with a confused ECU.

Hesitation was almost completely gone just brushing off the plugs, but I stopped by King Motorsports this morning and get NGK Iridium IX plugs (one step colder, 7 instead of the stock 6), exact plugs that Leonine is running. I'll let you know how things go now. I really hope these don't foul, too, cuz that means my issue is probably with my injectors (a slightly mroe expensive replacement). Update to come.

 

I sent my stock injectors to RC for a flow test. they will flow test them before, clean them, and flow test them after. 130.00 with overnight shipping. better than 400 for brand new.

Curious to see after 50+K miles with 87 octane what they were running at and what they will be after. I'll post the sheet they send me when i get them back.

 

Those temperatures are low my friend. Typical boosted temps are much much higher. The Rotrex can reach these extremely low temperatures, because it is not coupled to a heat source. Even being close to a header, temps as you can see are very low. Remember, the ambient temperature in New York right now is in the 90s.

-OJR

 

The only "hiccup" ive noticed thus far is if i floor it in vtec range while in open loop. i feel vtec kick in, and the SC catches up a split second later and i'm off... its never totally given up though...
if i were you i would disconnect the supercard and reinstall it, taking special care to make sure the injector clips are connected 100%...
also triple check ALL of the clamps, even the ones around the bypass valve, and especially the ones directly after the outlet on the SC. they are notorious for coming loose every so often if not tightened PERFECTLY! best of luck man...

 

yeah and i am sweatin my ass off

i bought the password JDM thermal intake gasket, mugen radiator cap which is a slightly higher pressure, and the colder plugs. my temp both water(antifreeze) and air temps have dropped about 8-10 degrees.

 

So I just looked up the formula for compressing air... in theory, if it was perfect adiabatic compression, 5psi would raise the air temperature from 90 to nearly 140 degrees without any influence from the header or anything else.

 

ah ok thanks for the clarification. I knew it was suppossed to run cooler than most f.i. applications, but then again, i wasn't really aware of exactly HOW hot most setups run.