19 psi boost. what the hell is goin on

[Guest]

i just installed a turbotech mbc and im having some problems. the car is running 19 psi of boost and i dont hit boost cut at all. it pulls really hard but it also misses a little if im heavy on the throttle. i cant back the mbc off anymore its at its limit. i just replace the o2 sensor as well. i cant make sense of it. i only want to 12psi and any idea of the misfire, should i get the ecu tuned for 98 octane fuel. any suggestions would be helpful please

 

[leebutts]

Are you sure you fitted it the right way round?

Have you got a quality gauge? What did it used to read without the MBC?

cheers

Lee

 

[Guest]

have you installed in the right way around?

pics of the install may help

 

[Peter_D]

Possible that the mbc is stuffed. You MUST hit boost cut at some point. As the others suggest get a decent boost gauge.

 

[weeaazz]

but we had suspicions about your ecu for a while,remember how it doesnt have a speedcut either,maybe its a realy good one,or a realy wrecked one

 

[jungle]

i just installed a turbotech mbc and im having some problems. the car is running 19 psi of boost and i dont hit boost cut at all. it pulls really hard but it also misses a little if im heavy on the throttle.

YEEEEEEEEEEEEEEHAAAAAAAAAAAAAAAA!!!!!

 

[whiteleg]

Once you've checked that the MBC is installed correctly check that you haven't disconnected any other vac lines or have a crack in any of them. Not hitting fuel cut at 19 psi would probably mean that your engine is not using a large volume of air. I hit 19 psi regularly but fuel cut will kick in at about 14psi after it has dropped back from 19psi. This is because at low revs the engine isn't consuming as much air as it does at high revs so the volume of air used at 19psi at 3000rpm will be less than 14psi at 5000rpm. Hope this makes sence. As for the misfire replace your spark plugs and or make sure they are gapped properly.

 

[Guest]

yea the mbc is the right way. i have just put new plugs in and they are gapped right. i have a speco boost gauge instaled as well to keep an eye on things. it runs 6.5 to 7 psi without the mbc. im actually working away at the moment so i have limited access to tools and a camera otherwise i would post up some pics. im suspicious about my ecu because im not hitting boost cut but nor do i have the speed limiter and i have done nothing to it. im stumped.

 

[godzilla]

Are you able to adjust it down? i dont get it, are you concerned about not hitting boost cut or the fact that 19psi is soon going to cause some damage?

 

[Guest]

one solution, get a good MBC..

 

[Outlanded]

Daryl is concerned about both, it is assumed that something is wrong with the mbc.

and it also appears that his ecu has no boost cut nor speed cut he has not removed the ecu to see if it is a factory unit of mines or some form of aftermarket, this will be done on saturday as his currently away for work.

 

[naughtika]

one way to find out.. have a close check on it..

 

[BuzzPuppy]

Well, I've got the turbotech MBC on mine and will hit boost cut on 16psi, if it helps as a reference point.

 

[Guest]

i say, if it works ok dont look. all you'll find is a Pandora's box.. but this can be fun alot of the time.lol

 

[Guest]

it's probably missing because it's running so lean. Dont expect your engine to last long with 19psi!

also a reason for not going down could be because your adjusting it the wrong way. Screw the adjusting screw the other way and see what happens

 

[Guest]

Wow 19psi. I hit boost cut for the first time this morning when it hit 17psi.