Got a motor and turbo kit from a buddy. He had it tuned, ran great for a few weeks, went out one night, beat the living hell out of it, and hasn't ran right since. I put it in my car, rebuilt the motor with 180 across the board with a new head and all gaskets.

Car back fires when it goes into boost. On the dyno, go completely lean as soon as it hits. I'm running 450 with propper fuel, ect. This is not my first turbo build, just my first issue with the leaning out.

Here's what I do know: The following were checked, and are good. Motor, turbo, wg, bov, fuel pump and pressure, vacuum, plugs, wires, dizzy, tune, ecu, timing, I think that's most of it. Oh, and no boost leaks.

Only thing I can think of is a bad injector, or somone told me the resistor box could be crossed, or have a bad continuity. Can anyone throw their two cents before I hack back into this thing?

 

How can you werify a proper tune on a car that isnt running right to begin with??
Are you sre it running lean as a misfire will show lean but actually be pig rich as the 02 sensor is reading the presence of excess air in the exhaust.

 

Also tuned with what?? I know Hondata does not like DSM 450s!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by D16Z6TURBO &raquo;</TD></TR><TR><TD CLASS="quote">Also tuned with what?? I know Hondata does not like DSM 450s!!</TD></TR></TABLE>


i dont know about that. alot of cars i tuned have run dsm injectors with no issues.

do you have a dyno graph? did u put the same type of fuel pump in the car that your friend had? do you have a fpr? what was the base fuel pressure on ur firends car and what is yours right now?

u need a retune

 

I will rephrase then Hondata themselves tell you not to run DSM 450s no matter what. That is all I was basing my statement off of as the only problem Ive personally had was with datalogging and resistor plugs so far

 

So im guessing you or your tuner kept adding more fuel on the fuel tables and it still ran lean no matter how much fuel you added correct?? If thats the case, i would clean or better yet test/flow/clean your injectors, check all wiring and resistor box wiring, check your fuel pump and fuel filter and run a relay off your battery to ur pump directly and what was your fpr set at?

 

It has a 255, idles at about 48lbs. The motor/turbo setup was tuned before, ran perfect for a few weeks, drove the living **** out of it one night, now runs like ****. Even after a rebuild and put in another car. The setup is the exact same. Even down to length on vacuum lines. Same plugs.

The car misses evan at an idle. The tuner said he would be able to track it down at another time, but this might cause me a motor by then as it has in the past. I work too much, and live way out in the middle of nowhere. I heard him say something about AF being a 12.9 to 13.4. I have no idea what that means. Just know it runs perfect till full boost, and leans out and backfires. You can go through the rpms, just no power. Plugs are chalk white after this. They are the BKR7es or whatever.

 

PS- I will be switching to Hondata AFTER it runs decently in boost.

We added 10%, did not change even by a hair. They said they have had the resistor box wiring do this once before. I'll try the injectors also. Just wanted to make sure I wasn't beating a dead horse here. Thank you.

Edit: It has Crome as of now. Not pro.

 

12.9-13.4 is way to dam lean for turbo engine....get another tuner..you are leaning out like no other...Plugs are gonna end up looking like casper the ghost

 

That would explain why he shut it down early and ripped the plugs out.

He's a great tuner. Just didn't have a lot of time to trace problems. He has multiple 9 second hondas. They took second at Import Face Off. They know what they're doing, just didn't have time to go through my wiring and test injectors.

 

Well i would stay out of boost until then or not drive it at all until that problem is fixed or that motor is gonna be nothing but paperweight. He shoulda told you that. and shoulda put a boost cut on your program to be safe so you will not boost. Do you have any pics of your fuel tables?

 

You need to solve the misfire before you try and tune anymore!!!
Misfiring will give a leaner reading than actually exists.
Why switch to a better management system AFTER when you can eliminate by switching to Hondata and different injectors now.

 

The car is parked. No need for a boost limiter as I won't take it past about 2500 now. I didn't want to put on the Hondata until this "bug" starts to get better in case it is in the wiring. I would hate to fry Hondata over Crome. We could not find any vacuum leaks, but I put on new IM and TB gaskets anyway. I guess I just rip the box out and injectors and just start over from there???

 

I don't have a graph near me for the fuel tables. I just know that at boost, roughly 48-5200, gear dependent, it craps on me. Example: 1st gear I can run through with almost no problems, 5200 in second it's got boost, then about 48 in third it's fully boosted. When I say full boost, those are the crap outs also. Hope that helped at all.

 

Yes, also run another compression check again...

Get new plugs and gap them lower, try another dizzy, try another resistor box and/or check wiring, and try another set of injectors if you have any or clean the ones you have..i would personally get them flow tested...

Start a fresh tune...

 

We've done 3 sets of plugs at 28, new dizzy, ect. Will test injectors first, then box and wiring. Thank you, just wanted to see if anyone had ever had this problem also. There's just too much stuff for me to trace, but now it is narrowed down. Thanks guys.

 

check the wiring on the injectors, one of mine some how cracked and was held together by threads sometimes it started and ran great, other times it didnt start. and other times it ran like this
http://www.youtube.com/watch?v=9grVTfkG5wo

 

if the tuner added 10% fuel and it made no changes to the a/f ratio, then most likely u are losing fuel pressure. u need to watch the fule pressure guage while you are making a pull on the dyno. if fuel pressure drops its either the fuel pump or the fuel pressure regulator. if you have a B&M FPR then i bet thats your problem

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by UncivilB18C &raquo;</TD></TR><TR><TD CLASS="quote">I don't have a graph near me for the fuel tables. I just know that at boost, roughly 48-5200, gear dependent, it craps on me. Example: 1st gear I can run through with almost no problems, 5200 in second it's got boost, then about 48 in third it's fully boosted. When I say full boost, those are the crap outs also. Hope that helped at all. </TD></TR></TABLE>

Dude I had the exact same problem 2 days after I got tuned, swapped out the OEM coil for a fresh one and it went away, 1 & 2nd were fine, would pull through cleanly then 3rd gear when boost went over 15psi it just hit a wall and went 13.0 lean and would break up. I dont see how this cant be an ignition issue, were you spinning tires in 1st and 2nd and then hooking 3rd?

change your coil.

 

See, this is what kills me. New dizzy while on the dyno. No change. Stock FPR. Will change after work. Idles at about 48lbs, and jumps to 52 at WOT. Never drops till you let off. Went through the wiring last night, was all good. Trying new injectors tonight as well. This effing blows.

Last thought. I thought the crome was screwy a while back because my idle changed. I've messed with the FITV ever since. Should I get a new one? Could that cause this many problems after the car is warmed up? Never thought about that...

Conclusion: Trying new injectors, fpr, tb and gasket, and possibly fitv if I can find one. Keep chiming in if you think of anything else.

 

my Dizzy was also new, sometimes new **** just breaks..... once again check the coil. You didnt answer my question, were you spinning 1 & 2nd and then hooking 3rd and then going lean? Remember the coil on my car still worked, it just could not keep up with motor, I denied the fact that it was the coil for a couple days until I swapped out my newish coil for an old one I had, problem went away.

 

Yea, that sounds about right with the 1-3 issue. I thought it was ignition just from the miss at idle. I'll try another one then.

 

Just out of curiousity what is your exact setup and is the vtec press switch enabled?

 

This is on my LST. Stock bottom, JG Engine Dynamics head stage 2, type r oil/water pump, timing at 16, NGK BKR7s at 28, NGK wires, blox log style, borg warner 57 at 11lbs, tial wg, hks bov, ebay fmic, dsm 450s, walrbol 255,...not exactly sure what else you're looking for. Pretty plane jane run of the mill stuff. This is why I'm going crazy. Oh, and crome. 93 octane.

 

28 gap???? lol you better gap that down, I am at .016-.018, try around 25 and go down from there.