So i began a thread over in Engine/Transmission/Maintenance . but the focus has switched over to more of a forced induction Question. So here whats is going on, last saturday night i took the car out for a ride. eventualy i decided to open her up and i did but soon there after the car started haveing issues boosting.
the best way to described whats going on is that when i get on it at about 3000, give or take a few rpm's ,it begins to just bog down and back fire. i believe its misfiring. it only happens when the car hits around 8 pounds of boost. odd thing is that my a/f is staying around were it used to . 13-11 range. the spark plugs are gapped to the correct gap .30 . my head gasket is good 205 - 210psi accross the board. it has new plugs and wires . the cap and rotor look good. i tried going back to an older fuel map to see if the problem would go away and it stayed. i should also note that the issue happens 90 percent of the time but not always.
i am running out of ideas and could use some help.

ps here the other thread i started
http://www.6gc.net/forums/index.php?showto...mp;#entry654965

Sounds like detonation. Lower your boost and add more fuel. You should be in the low 11s under boost.

can detonation just pop up like that? becuase for months i havebeen boosing at 17psi and have barely had any issues. and thoughs were high in the rpm range 4500 +

er umm... why were you boosting 17psi on a 5sfe?
How much boost are you at now?

This post has been edited by lagos: Mar 18, 2008 - 10:14 PM

the car isn't a stock 5sfe. its all forged internals. i haven't changed the boost settings yet .( Still at 17 psi) the car isn't a daily driver. more of a project car. Its just sitting in my garage while i try to figure out what happened.

This post has been edited by blckcelica95: Mar 19, 2008 - 7:58 AM

What are you running in terms of engine management.
13 is cutting close on an AFR.....you don't really want to see higher than 12.5 at an upper limit.

I would also turn the boost down. Detonation which starts to screw with your timing sounds like a very valid cause

get new plug wires. i kid you not. i couldn't boost more than like 4psi with old oem wires. they leaked voltage to the head and would cut out only under boost just like your explaining.

>
it may be just a coincidence but i just i changed my plug wires .

>

again, the fact that you have forged pistons has nothing to do with it. 17psi is way too much boost on a 5sfe running pump gas. the ct26 is exhaust side limited and the higher you push the boost the higher your egt's go up. Your also doing this with no way to monitor knock and your a/f ratio is too lean.

Turn the boost down to about 13psi, and tune the car to a LOW 11afr. I bet you the problem will go away.

>

Def listen to Lagos.
But about the above statement: Did the problem start with this? Wire manufacturers do make a bad set sometimes. Maybe throw you're old wires on there and see if the problem goes away?

>
ill deffinatly give it a shot . i do have the devils meth kit on her also if that makes a difference
but what is puzzleing me is that i have been running it at 17 psi since september last year . and the problem just showed up.

Who knows, maybe the change in weather threw your a/f off or you didnt make pulls all the way though the rpm range. Either way, 17psi is too much for a 5sfTe with a ct26... even with water injection.

Btw, what kind of fluid are you injecting?

just using winshsheild washer fluid, as soon a i can i am upgrading my turbo also
just looked at my plugs wire they were arching .. dam bosch wire never should turst them

did the problem go away when you put your old wires on?

I havent been able to check yet . some personal stuff came up . so it wont be able to check till tommorrow.

This post has been edited by blckcelica95: Mar 19, 2008 - 3:24 PM

>
ouch.

i dont like to post in these types of threads, unless im pretty sure what it is.
art is right, 17psi with a ct-26 is not really much use on a 5s, hell, much over 15-16psi even on a 3s is kinda pointless.
bosch wires...BIG no no, especially since your turboed.

new OEM wires, cap and rotor, once a year. at least.

if your needing to run 17psi on a ct26 to make the car fast enough...i would say its time for an upgrade, especially if you have forged internals.

:edit:
i just read your profile.
it says 50 trim to4 compressor in a ct-26.
all that compressor, with no exhaust side work, is pretty much usless, especially on the 5s, we need more flow.
you'll be making a few more hp than a normal 26, with ALOT more exhaust manifold pressure. (more heat) yes, the WI will help with that, but you'd be much better served with a bit larger exhaust housing.
since its a "project car" sounds to me like its time for a larger turbo!
hehhehe

bigger turbo is next on the list !! the exhaust is clipped. im still debating on my next turbo. i think the government will be buying it once we get that check were suppose to get in may. and if the my old wires fix the issue im going right down to Toyota and ordering everything. yeah 17 psi is a bit excessive on a ct-26. but as everyone says " boost is addictive " lol

This post has been edited by blckcelica95: Mar 19, 2008 - 4:12 PM

x_itchy_b_x was right swapped back in my other pair of wires and bam all gone. but i am going to turn down the boost anyways 17 is a bit accessive. but i have a new problem i just fell in my pit and messed up my knee, so i cant shift it never ends lol

This post has been edited by blckcelica95: Mar 20, 2008 - 1:05 PM

nice
it was a pain to figure out on the side of a highway when it happened to me.
glad that experienced helped someone else out.

This post has been edited by x_itchy_b_x: Mar 27, 2008 - 8:28 AM

nevermind

>

Toyota really gave us a crappy EFI system with these cars. I mean, todays modern cars can go at least 60k without changing the ignition components, even the turbo ones. Im willing to bet that we wouldnt have so many ignition issues, if we had coil packs instead of a cap/rotor. Megasquirt is looking better and better every day.

Then again it costs us what $100 to replace all the components with good NGK stuff? i do it like every 6mos and that's not a bad hit to the wallet IMO. When you have coil packs things get expensive - but the interval goes down so IDK. It's probably a trade off. The 4th gen guys have a fair amount of troubles with the coil packs from what I've seen so

>

really? what sort of trouble?

I tried all the links I had favorited but evidently it's been too long [Been a while since I had that 4th gen motor laying around for a swap]. I'll keep looking for you and find that info.