After much research, I have seen some folks go as far as to replace the wastegate, but I believe my problem is a little different. I have a uego wideband a/f, and since my car was acting up a little more than normal and it was around 40ish outside, I noticed at these rpm's my a/f's are going midly lean then drop back when I get power back.

I have 400.8 whp and only 380cc injectors, could I have outgrown the injectors? I know that an upgraded fuel system would help, and I have just recently been given a great deal on one, I will install in it a month or so. Any suggestions on my diagnosis or could it be the wastegate, the car is holding steady boost and isn't overboosting, just to address some previous suggestions.

 

400 rwhp doesn't sound right for only 6.67 psi. What's going on there?

Respect
JET

 

same thing i was thinking, you might have been running lean this whole time, thats the only way i see that kit making that much power at that boost, just my 2cents

 

how lean does it get? Does the engine abruptlly cut out? What other symptoms.

 

Forgot to mention my injectors were running at 98% duty cycle as well and I have already addressed the doubts of the hp with dynographs as well as before the tune on a dynojet at 377 whp and 358 rwtq and same tune on a dynapak was 364 rwp and 338 rwtq same tune 2 days later. Do a search on 400.8 hp, you should find it.

 

does the whole car turn off? im having similiar problems but i have the fixed pipe turbonetics sent..hmm

 

your injectors are at 98% duty cycle and you're making 400whp?

Something doesn't seem right at all man. Seriously. Craig made 412whp on 9.5psi and I doubt he's past 85% duty cycle on 'em.

 

That's very impressive if he still has 380cc injectors. 380cc~ 380whp at 90-95%. I could believe he was at 85% if he had 440cc injectors.

 

The car doesn't die completely it just loses power well all power in the engine, kind of similar to a hiccup. The fixed pipe is for overboosting right, or are there more than one fix for piping?

 

Yes the wastegate upgrade is for over boosting... Which clearly for you is not the case.

I thought you got a good tune? If the injectors are maxing out then you wouldn't be recovering from that, but you sound like it does go back to rich... So I think you need to just get richer quicker.

I still can't believe the power you put down with less than 7 psi.


And where is you A/F graph? Did Knowledge not print one out for you?

That would help.

 

I know of someone who has taken these Denso core 380cc up to 450whp or so with higher fuel pressure. (not on a TN kit)

It might help if you actually explained your problem more, or included a dyno sheet with AFRs.

The problem you're having sounds to me like an MAF issue or a boost leak... Although I can't imagine how you're making so much power if this is in fact a problem.

By the way, the Craig that Mike was referring to is me...

 

A fellow Craig, not to many of us... Anyway, I had a dyno with the a/f's, but I don't know where I put it, I remember it being similar to the dynojet's a/f I posted, but that really doesn't help any. It may be a MAF issue, but I don't it is a boost leak, I double checked everything and everything is zip-tied very well.

In explaining the problem more, this is as a good as my feeble mind can do:
Under hard acceleration (especially when it is cooler outside, and I have romped on the car for a period of time), the car hesitates under WOT around 5k rpms and within 200 rpms the car recovers and pulls to the red-line very hard as if nothing happened at all. For instance, if my car goes over 1100 degrees on the EGT gauge the problem is more evident, also if the temp. outside is under 50, my car acts up. I have tried to pay more attention to the a/f's and during this "hiccup", my car definately goes lean, higher 11's to very low 12's, recovers to 10.8:1 or so. My car has done this since I have had the kit, even before the tune.

 

Well since it does recover, I think it is in the tuning. Also I don't consider high 11's as lean lol.

 

I suddenly realized you have a UTEC. This is definatley a tuning issue. That cut you are feeling is probably an overboost cut. The UTEC reads ahead a little bit, and if you are overboosting beyond what your tuning dialed in, then you are probably hitting the overboost fuel cut. I have tuned engines to 8psi, with the overboost cut set to 11psi, and the UTEC would still cut fuel, even those boost never exceeded 8psi. Jermaine said a new firmware upgrade will solve this issue. In the meantime, just have your shop riase the overboost cut up a little bit.

Did your shop road tune the car? Usually, these symptoms show up during road tuning, unless your car has suddenly started overboosting.

 

"KABOOM"
is a real expensive saying, dyno it...no wait..your cutting out, if your tuner does alot of runs with it leaning out dont wanna blow up, your in a bad situation. Hate to bear bad news but this is what your risking right now, your motor. Personally i wouldnt even of took my car back from the shop cuting off after a tune, you gotta know something about tuning and AF if you go FI on a Z

 

WEll that is a bit scary....Suggestions? I can get it looked at and all, but I am not sure about spending more$$$ on re-tuning, should I get the fuel upgrades and then a tune, what to do?

 

omg i was getting this too before i incenergrated a piston.. it was weird my boost would go up and then it would keep going a little but it felt like fuel got cut off or something to my engine.. then i step back on it and the power was there again? does detenation happen when this takes place also? and yeah i blew my built motor.

 

AND DUDE.. STAY OUT OF BOOST.... SERIOUSLY i was running forge actuators and rc650 cc's with the aps fuel system.. and a utec... i thought it was a boost leak at first but this makes alot more sense!

 

ohh and this didnt happen when my motor blew either..it happened to me like twice on the highway and i didnt get on my car anymore... but i had a ticking sound like a valve was loose.. now i think it was a piston ring... i parked my car and drove the civic.. but when i was driving my car up to my tuner/builder to look at it.. thats when it blew on the highway.. the damage was already done .... thats so weird this utec is doing this.. the GREAT UTEC RIGHT!

 

+1 Mike @ AAM found this out on my car when tuning. We were like WTF? when it was happeneing, glad he figured it out....