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Boosting issues

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Old 02-16-08, 04:59 PM
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ucfa4
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Default Boosting issues

Ok so ive had my 1jz in my sc for about 6 months and had no problems. Now when im driving and the car starts boosting it seems to be hitting a boost cut. Its wierd b/c i never had this problem before. If i just keep my foot floored on the gas the car will start jogging , by this i believe the car is overboosting and cutting the fuel. I need some help guys. Do you think a bcc will fix it?
Old 02-16-08, 05:53 PM
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Dx3
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I ran into the same problem - also thinking it was boost cut. Turned out it was a spark problem at 4k rpms. I replaced my cap and plug wires and it fixed it. Not sure this is your problem, but don't count the possibility out...

Jonny
Old 02-16-08, 05:58 PM
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Originally Posted by ucfa4
Ok so ive had my 1jz in my sc for about 6 months and had no problems. Now when im driving and the car starts boosting it seems to be hitting a boost cut. Its wierd b/c i never had this problem before. If i just keep my foot floored on the gas the car will start jogging , by this i believe the car is overboosting and cutting the fuel. I need some help guys. Do you think a bcc will fix it?
I would change the plugs, another thought is gas....did you stop and fill up right before this started happening?
Good luck
Dan
Old 02-16-08, 07:18 PM
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Now that i think of it i did nearly run my car out of fuel and filled up before this problem started. What plugs and wires would you guys recommend?
Old 02-16-08, 07:19 PM
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Originally Posted by ucfa4
Now that i think of it i did nearly run my car out of fuel and filled up before this problem started. What plugs and wires would you guys recommend?
OEM wires, NGK 3330 plugs

Jonny
Old 02-16-08, 10:55 PM
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lfrers
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Same prob here turned out to be crappy BOV setup.

(BTW If anyone could tell me... what would a bad or poorly functioning waste gate cause???)
Old 02-17-08, 05:35 AM
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1jz's dont have caps and plug wires. Only coil packs.

Check for cracks on teh coil packs, maybee vacuum leak somewhere, what is your A/F at the cut that should be a good indication if its a boost leak, or another problem.
Old 02-17-08, 06:44 AM
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I figured thats what people ment by the wires. Im going to check that out. I have n idea what my air fuel is b/c i do not have a guage. Im guessing it has something to do with the boost. Im going to chek it out tday.
Old 02-17-08, 08:00 PM
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I experienced the same prob around 4k rpm, first I checked my plugs and then after researching here on cl I determined I was boost cutting ordered the fcd and probs gone and I beat vettes on the highway with exh and air filter.
Old 02-18-08, 06:48 AM
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I determined that the problem is something electrical cutting out at certain boost levels. I ordered a bcc and will see if that fixes the problem. Thats the thing about project cars, it seems that there is always something wrong wth them. Thanks for the help guys, ill let you know what happens.
Old 02-18-08, 09:28 AM
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Originally Posted by lfrers
Same prob here turned out to be crappy BOV setup.

(BTW If anyone could tell me... what would a bad or poorly functioning waste gate cause???)
If it gets stuck, it will boost until you take your foot off the gas (think 30lbs, then boom!.)
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