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M35 Power Drop

knightdesigns
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knightdesigns Rookie

knightdesigns

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Posted

Hi i have a 2001 250t rx and it has recently begun to act a bit strange.

The car has always driven great, and been a rocket generating plenty of thrust in the top end, however recently when i was coming up Mt Vic, it suddenly dropped power/boost and seemed to be only running at about 75% of it's normal output.

I thought at the time the ecu may have dropped power due to things getting hot ? however my temp gauge was all good.

I backed off and pulled over, restarted and as i went over the top of the Blue Mtns it seemed to come good and bounce back, so i thought it may have been a temp thing.

Over time its started to do it more regularly, to the point i thought i may have had a blocked exhaust/ cat etc as i also noticed one of the pipes coming out of the muffler tip didn't seem to be flowing at all.

I visited my exhaust guy and we pulled the pipe off at the cat and pre muffler and took it for a run and still no improvement, so i guess we can eliminate the exhaust.

However a system scan of the car revealed a fault with the knock sensor.

Could this be the culprit ?

any help would be appreciated

cheers

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Commsman Veteran

Commsman

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Posted

What was the exact code?

Faulty knock sensor could do it I suppose. If the ECU retards the timing heaps it will feel down on power. You didn't just get a bad tank of fuel (I once bought premium & got standard)?

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knightdesigns Rookie

knightdesigns

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Joshm THANKS !

i think that link described the problem almost perfectly

i'll make sure the knock sensor is ok then look at the boost solenoid

can anyone tell me the location of ....

the knock sensor

the boost solenoid

and where i can buy them ?

thanks again

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joshm35 Veteran

joshm35

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Posted

Boost solenoid is on passenger side of engine half way to the back of the engine beyween the block and aie intake hose. Its held on by 10mm bolt with 2( 7mm) hoses going into it. Hope tjis helps. Theres a pic somewhere on here that shows it

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scotty nm35 Grand Master

scotty nm35

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Posted

You don't want to change the knock sensor, it's a fairly big job as it's down in the valley, under the intake lower plenum.

If it hasn't thrown a code then the ecu is simply trying to ruin your fun. Bypassing the solenoid will stop this, just get a joiner and plug the two vac lines into each other. (Don't replace them as there is a restrictor on one.)

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