Overboost Problem....

[jserr68594]

I have a 92 Typhoon that is stock other than an aftermarket intercooler pump and 3" ATR exhaust. The previous owner removed the cat. converter and disconnected the boost control solenoid. I am unsure if he played with the wastegate at all. I have connected the solenoid back up. The truck cuts off at higher RPM's and I am pretty sure it is overboost.

How do I fix this? Do I need to reinstall a cat. converter to solve the problem? How do I check to see if the wategate is properly adjusted?


Thanks,

Justin

 

[jwaller]

Re: Overboost Problem....

you might need to reinstall the cat but I'd be sure the stock system is working the best it can before you go that route.

remove the WG rod from the flapper arm, you should have 7/8 pin covered by the rod, or preloaded.
now with the actuator running a direct boost signal(no solinoid) you should have ~8psi of boost. now reconnect the solinoid as it should be and test it out.
you should have a real boost gauge so that you know exactly whats happening.

 

[Bill Z]

Re: Overboost Problem....

Do you have pictures of the vacuum lines on your turbo. They could be connected wrong. There should be a vacuum connection from your turbo to the back end of the accuatator and the front end (closest to the airconditoner compressor) of the actuator down to the waste gate diaphram. The electrical connector must be connected to the accuator.

Hope this helps. (pictures are better than 1K words)

 

[JohnnyPC1]

Re: Overboost Problem....

Correct me if I'm wrong, but also consider this may be the effect of the rev limiter that kicks in around 4800 (?) rpm on stock trucks?

 

[bezerk]

Re: Overboost Problem....

Correct me if I'm wrong, but also consider this may be the effect of the rev limiter that kicks in around 4800 (?) rpm on stock trucks?

shouldn't it just shift, before it cuts off?

 

[jserr68594]

Re: Overboost Problem....

It is definitely not the rev limiter.

 

[dgoodhue]

Re: Overboost Problem....

I would double check the wastegate adjustment incase he fooled with it to make spool up faster. Most likely he probably disconnect the solenoid to prevent overboost.

 

[JohnnyPC1]

Re: Overboost Problem....

You would figure, but from my newbie perspective, and probably having a messed up transmission, mine would rev past 4700ish and start bucking like crazy...I would attribute that to a rev limiter. I changed out my stock chip and found that with the rasied rev limit of the new one, my tranny would now shift at about 5000rpm right on scheule...