Overboost Problem

[cjroche270]

Hi all, long time follower first time poster. I recently had my fg xr6t ute custom tuned to 288 rwkw. It has got pwr cooler, coolerworx piping, rapid intake and battery relo, cat, twin 2.5 cat back and injectors. Have just driven 1300kms from qld to nsw and have got a problem with over boosting. Dyno graph shows boost peaking at 16.5psi and tapering back from there. In any of the first 3 gears boost will spike to around 19 psi and sounds like its misfiring. If I bring the boost up slowly it will hold better at the right boost levels but a gear change will send it even higher, zf by the way. Anyone got any ideas I don't want to do any damage. Maybe actuator not opening properly?Thanks

[Kosij]

Who tuned it?

[f6mark]

chick all ya cooler pipe's mate. u may have a lose cooler pipe.

[cjroche270]

Tuned by hi torque, so I'm confident there is nothing wrong with that side if it. I will check all cooler pipes, would it be losing boost if there is a loose joiner? I was going to do boost solenoid maintenance, not sure if it will help but ill try all basic things first, is there anything similar I can do with the actuator?

[f6mark]

Tuned by hi torque, so I'm confident there is nothing wrong with that side if it. I will check all cooler pipes, would it be losing boost if there is a loose joiner? I was going to do boost solenoid maintenance, not sure if it will help but ill try all basic things first, is there anything similar I can do with the actuator?

yes mate it will over boost if u have loose joiner mate.. have a good look all over mate.

[cjroche270]

Ok I'll check them all over and see how that goes. Thanks for you're help

[f6mark]

anytime mate. hope it work's out for ya mate.

[Freight Train]

depending how its tuned if the dyno opperator doesnt get on it hard in the begining of the run it wont run as much boost as it will if its held more time to spool up and an auto will always slightly increase boost after a gear change because the turbo is moving more air then it needs to to maintain said boost level at lower revs vs higher revs, if you're sitting on the highway cooling everything down you're going to run more boost with the intercooler ice cold then when its hot, also are you sure your boost gauge is 100% accurate compared to the dynos boost gauge, the miss firing is probably the spark plug gaps, they tend to not do it at that power level when theyre warm but if you sit on the highway and cool down everything a fair bit they run slightly more power and blow out the spark

[cjroche270]

Yea that would make sense as it happened worse on the highway when dropping back to overtake. I have tightened everything up and is a lot better it still creeps up in 3rd but is ok if I feed it in slower. Other gears seem ok. Boost gauge is only a cheap speco so probably isnt the best. I think it must have been the joiner between tb elbow and tb as it was the only one that could be tightened or the stock bov as the plunger thingo inside wasn't centred. Is there a better choice in spark plugs as it only has stock ones in now. Appreciate the help from you guys has put my mind at ease now

[BigAl's04]

http://www.fordxr6turbo.com/forum/topic/83346-spark-plugs/