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Discussion Starter · #1 · (Edited)
Help

ok so i have a intake/mbc/2.5" turbo-back/air fuel-boost guage- so i dont have a chip yet but while i boost it at 12, it will get to 12 easy but when i hit 12 itll vibrate. i have a probe intercooler and its in nice and snug. and i dont think it is a boost leak because i had it before and the car just stopped boosting. it will get to 12 and the boost guage will move back and forth 11-12 and my air fuel is 2 bars away from rich. maybe a ignition problem? i also have a race soon so i wanna figure this out so i can wack him by 5 cars and win some $$.
and its a bone stock crx. kid thinks its- fast.
thanks
 

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Yeah, when it "stops boosting", it's because you reach boost cut. The vibration could be one or more of several things. Check your transmission mounts first and back your boost down a little. Keep it between 10-11psi until you get a chip and the sufficiant amount of fuel to support your mods.
 

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it could also be your ignition wires... my car used to have the problem where it would be running great untill i was around 12-15 psi then start shaking and struggling. It was from a bad ignition wire that wouldn't stay tightly connected to the spark plug (remember that one tyler?)... new set and it happily boosts to 15psi.

Does your chime start making noise when it shakes? if so, it's air flow/fuel cut like tyler and mazdaman said.

-Todd

P.S. don't forget to give the crx a head start to make it more fair.
 

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Discussion Starter · #5 ·
i have some bad name sparkplugs in there. split somthing. i should check the gap for how much and should i open the gap or close it for more boost. i think close. and what are some good plugs. v-powers? and what kinda of cheapy wires will do the job.
thanks guys this race will happen on mon/tuesday so ill fill you all in when he looses some cash. hes probably gona talk shit till it comes down to it
-thanks
 

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:lol: Yea I remember the faulty #4 plug wire on your 626! The weird part is my #4 wire the clip broke inside that connects to the plug as well. In my cardomain I have 3 black wires and 1 blue wire I took off my LX. I guess I should order a new set so it doesnt look so ghetto :lol: Even though the blacks wires were new too :( I also had the rethread my head due to the #4 plug that was improperly installed byt the shop the previous owner got the wires and plugs done at.

Ok, I'm done hijacking.

-Tyler
 

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Discussion Starter · #7 ·
ok so i went out boosting and was messin around with some civic's. and i was hittin 10psi and this vibration was happening!! i won. but not as many car lengths as i wannted. this is kind of worrying me because i want to be boosting smooth. it comes aroun 4-5k i have it set at 10psi. and i get that vibration and its staying at 9-10 when this happens. i dont think its fuel cut because its happening before 12psi. i checked out my injectors and they sounded alright. im kinda towards the ignition. would it really cause this?
 

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It could still be fuel cut before 12psi if you have a boost leak... the cut only happens when the computer sees that there is too much air coming into the system, it doesn't have any boost sensor at all. If you could somehow pressurize the system to 30psi without flowing too much air, your computer wouldn't do anything about it.

But yes, ignition could definitely cause this. If one cylinder isn't firing right your engine won't like to keep the boost up, and start running poorly...

Just spend some time checking things out first. See how your plugs are, your wires, your throttle body boot, your cap and rotor... and make sure all your hoses don't have any holes and are clamped tightly.

If it is your plugs or wires, get some ngk plugs and some good wires, don't cheap out because crappy wires will come back to bug you later.

-Todd
 

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Vibrations?? Do you mean a studdering under boost??? Plugs and wires as everyone is saying.
When I feel vibrations I think, tires, tire balancing, alignment, and/or the exhaust could be rubbing.
 

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Discussion Starter · #10 ·
ill get the plugs/ wires and make sure that works. tires are good and balancing is a-ok
thanks
 

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Also, make sure you gap the plugs right.
Just go slightly lower than stock gap, since your running more boost.

I run .28-.30, but I run a good amount of boost.:)
 

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Discussion Starter · #13 ·
hey well i found out a problem that links to the vibrations. my compression is 60 60 25 60. i put oil in the the 3rd cylender and it jummped a little to 60. im also going towards a timing problem. cam wise. any ideas? when i start my car it goes to 500 and pickes itself up to 750 where it should idle, when i go to drive it, it kind of pudders unless i floor it which it boosts rapidly. im going to the shop tomarow to follow through with a cylender compression and see where it is leaking. if any of you have a write up for fixing the cam timing and how to check it, i would really be thankfull.
thanks
 
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