What's The Purpose Of Monitoring Turbo Boost Pressure

[hyacc]

Hello all,

I have no experience with turbocharging and recently I bought a hilux with a turbocharger. I've seen these boost pressure guages and smart guage that display Turbo boost pressure via OBDII connector.

Could anyone familiar with turbo charged vehicles explain the purpose of monitoring the "Turbo boost pressure"? Should I care about it while driving? I've read once if TBP is too high, fuel consumption will increase. Does it indicate the health the of Turbo system? . Vehicle manual only states the idle time before turning off engine after heavy load/high speed driving.

Thanks.

Edited September 3, 2010 by hyacc

[Crazy Life]

since ur turbo is an oem,you should be fine with the standard turbo,but if you want the easiest method is to get a gauge,instead of a smart gauge.

senior member,please share your ideas

[Skyline R33]

My car had a factory turbo and when the turbo is not running the meter normally shows (-) pressure which means for vaccum and when you press the pedal turbo kicks in and the pressure gauge will show (+) figure. The gauge normally has positive and negative dials with a zero in the middle. When you know it's on the positive side you know the turbo is working. If you wanna drive economically try to keep it below zero always in other words don't make the turbo engage. If you boost the pressure too much it can damage the turbo which could also cause it to explode. I think the gauge is there so you do not exceed that limit but my one was running 7psi factory and I've never dared to touched it. You could normally go up to 3.5psi stock without any issues AFAIK. If you want more pressure you might need a after market inter cooler and better piping/dump system. This will be more suitable for performance vehicle. I guess a turbo charger is the similar version of a turbo in a petrol vehicle but the only difference is it is coupled with the engine so the functionality should be similar too. (correct me if I'm wrong). Hope this helps.

[hyacc]

Crazy Life and Skyline R33 thank you for valuable info.

[hyacc]

So I think turbo boost pressure increases when you press the accelerator pedal and if TBP becomes too high while driving what should be done?

If you should care about it, why a gauge to monitor is not fited by toyota?

[Skyline R33]

Most of the cars with a factory turbo have a guage fitted by the manufacturer but not dure about a Hilux though. If you wanna release preasure some cars have a manuel button in the cabin. For it to become too high I think you should be pressing the peddal quite hard for a while and you could see your rpm meter increase too. Just take your leg off the pedal and that will immediately get rid of your pressure as the engine will be in vaccum. I don't think you will blow your turbo/engine with normal driving conditions in SL. Even getting it to kick in migh be harder as it needs a little time and acceleration to kick in. If you wanna shoot from the lights or do a drag with some one you could do a "toe heel" trick. Thats pressing the accelerater with the heel and pressing the brake with toe of the same leg to get the boost to build and take the toe off suddenly.

[Watchman]

Skyline, machang the turbo itself kicking in has little to do with fuel efficiency. Its the RPMs. Even a N/A car would burn more fuel if its working more on the higher end of the rev range... And a its a deisel turbo, so they dont spin as fast as they do on petrols so the chance of it 'blowing up' are quite minimal. At least i have never heard of it.

And your appication/use of the heal-and-toe shift is quite wrong. Its normally used in downshifting around corners, not at the launch. The objective is to keep the engine revs from slowing while also using the break to help the car slow down while also changing (downshifting) the gear to prepare you to exit the corner... If you're at a traffic light, you dont need to keep ur foot on the brake, do you? there's the handbrake for that..

And at hyacc: machang dont worry too much abt monitoring the turbo boost. But what you need to do is let the engine idle for a while before turning off the engine. If you have a turbo-timer you shouldnt have to worry about that either. There were quite a fre threads on turbos and using.maintaining them. google it.

[BLu3HaZe]

AFAIK, a turbo on a diesel helps improve the efficiency by increasing the cylinder pressure, which is normally not a lot when using a N/A diesel engine. As there are no spark plugs either and high CR, it'd make diesels more efficient if you do NOT try to lay off the turbo. Don't want about blowing up a turbo in a stock Hilux, cuz the factory has set the limits very much on the safe side, you can't increase pressure too much unless you over rev the engine way too much, by selecting a lower gear than you should be in or so. If you were to remove that turbo from your diesel and drive normally, you'd obviously lose power and a very big chance of actually getting LESS km/l

It's totally different with petrol engines though, where turbo's are added for power.

[madmax]

Simple, it gives you something to talk over dinner!

[BLu3HaZe]

Simple, it gives you something to talk over dinner!

Unless you're talking with a normal girl or a pathetic guy, in which case she'd (for both) leave you talking to yourself Happens to me