while reading one of 1300cc.com's articles, i read that there is an electronic boost controller that raises the boost from 5.5- 7.5-8psi. My car has been having boost problems as many of you may have seen me post about (turbo builds boost erratically; sometimes boosts to about 5.5 then drops to 3ish...) basically it's having problems ... so since the max boost i've ever gotten is still about 5.5psi, could it be that my stock boost controller is gone or am I barking up the wrong tree entirely?

 

Two questions to start off.

What year?

How are you reading the boost?

James

 

two questions answered:
1990 - 125k on body and turbo, 35k on engine
stock boost guage (blush... is it really thaaat bad?)

Oh, and I know that it is in fact dropping cuz you can hear the turbo's whizz slow down. (wiiiiiiiiiizzzzerrrrr) :-)

 

It's quite possible, you can always test the little actuator to see if it works, it's around the oil filler neck somewhere IIRC.

 

The stock boost gauge is not bad if you are looking to see if your boost sensor passes the self check. When you turn the igntion on (car not running) the needle should go to about 0 kpa.

But for diagnosing a boost problem it is not the best tool.

You should get a boost gauge. It will make life much easier. Hell, for testing purposes you can hook it up and run it through your passenger window and do that.

Now, do you have the stock exhaust?

James

 

You are looking at a picture with the intercooler removed. That is the controller. IMOP you should get a boost gauge before you start barking up this troubleshooting tree.

James

 

if the controller is working or not it should never go under 5.5psi. is so it's a mech. problem. not electric.

 

One quick and dirty test is to bypass the stock boost actuator.&nbsp Once the actuator has been disabled, it should build boost like a Zenki model - peak at about 7psi, but it should stay steady arounf 5-6psi.&nbsp I'm talking about stock exhausts here...


-Ted

 

hks 2 1/2 exhaust. what does that change?

I never knew the gauge zeroed itself with the ignition at "on"... i'll check that today...

 

With just the exhaust, it should do closer to 7-10psi with the boost solenoid bypassed.


-Ted

 

Yeah, the gauge definitely does not get up to 0 when i put the car to the on position.

7-10 psi... HA!!!! It's a good day when mine hits 5psi

 

Sorry, not sure if you have a catback or a full exhaust. What exhaust do you have from the back of the turbo to your tips.

Basicly, what I am getting at is are you cats clogged?

James

 

i don't know... it's a full exhaust and i THINK high flow cats... but i'm afraid to take the cats off or try cuz i heard the bolts weld themselves and/or get very brittle and may require welding to get back together.... i'll be under the car this weekend.. i think the best i can do i knock the cats with a wrench and listen for rattling. what should i do? oh, and would having clogged cats make my boost fluctuate so much?

 

please answers ANYBODY!!??

I just took this video. Don't enlarge it or you can't see the gauges clearly.
http://www.jmujack.com/rx7/jacksrx.avi

 

Huh, i looked at the video. She sounds really good God i miss my rx7

But it looks fine. Mine does the same as your does.

You need to get a boost gauge man.

Your doing a lot of worring.

James