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-   -   Too Much Boost! What's wrong? (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/too-much-boost-whats-wrong-527370/)

AdamP 04-07-06 01:01 PM

Too Much Boost! What's wrong?
 
Okay so I have stored my car for the winter and just put it on the road yesterday and low and behold I have a boost problem. The car feels like the waistgate is stuck closed. Not good! I get way too much boost. Has anyone had this before? Upon causal inspection it doesn't look like any hoses have popped off, and I am thinking my actuator may be stuck or something. I will dig into the car more in the next couple of days but I thought I would throw this one at you guys to see if I can get some good places to start. Any ideas, thoughts or suggestions? Thanks

DamonB 04-07-06 01:04 PM

If it's overboosting and hitting fuel cut before it even transitions to the second turbo check the hoses and connections between the two solenoids on the front of the UIM and the hardlines.

AdamP 04-07-06 01:07 PM

I will go check those now. I don't let it hit fuel cut, I keep to close an eye on my boost gauge and ever time it wants to shoot past 10psi I let up. I am too scared of blowing my motor to just floor it.

KBSRX7 04-07-06 02:22 PM

Becarefull
 
I'm not sure what the problem could be.Its been awhile since I played around with the stock setup. I DO know that you can blow the engine faster then you can fix the problem, so be carefull!

dgeesaman 04-07-06 02:38 PM

Definitely make sure the actuator isn't stuck. Also make sure the lines leading to/from the actuator have no leaks. (Over the winter, you don't know who/what made a nest or chewed them).

If you have a Mityvac, pull the line where it meets the turbo nipple and apply pressure with the engine off. It should move the actuator fully open at about 8psi.

Dave

AdamP 04-07-06 02:41 PM

Thanks guys. So far I have checked the hoses going in to the solenoids at the front of the Upper intake manifold and everything seems fine. Without taking the upper intake manifold off I looked as best I could to see anything that is wrong, and it doesn't look like it. I am going to see if I can get the actuators to move myself, but I am not sure I can get a good enough angle on them to get the leverage I need unless I put the car up in the air.

DamonB 04-07-06 02:42 PM


Originally Posted by KBSRX7
I DO know that you can blow the engine faster then you can fix the problem, so be carefull!

The ecu has a fuel cut in it so you don't blow the engine. It with a wastegate failure it overboosts until it hits fuel cut to save the motor. I have tested this system because years ago the wastegate solenoid failed during a run and I as I mashed the throttle the car would accelerate and then braaaaaaaap; fuel cut. I'd let off, mash the throttle and braaaaaaap fuel cut. I did this a couple more times before I checked the boost gauge and saw 15 psi on the primary just before hitting the cut. Motor is just fine.

dgeesaman 04-07-06 03:12 PM


Originally Posted by AdamP
Thanks guys. So far I have checked the hoses going in to the solenoids at the front of the Upper intake manifold and everything seems fine. Without taking the upper intake manifold off I looked as best I could to see anything that is wrong, and it doesn't look like it. I am going to see if I can get the actuators to move myself, but I am not sure I can get a good enough angle on them to get the leverage I need unless I put the car up in the air.

The hoses you need to inspect run from the wastegate solenoid down to the primary compressor housing. The most you will need to remove is your intake to see the lines and the pressure chamber to see the solenoid. There is nothing under the UIM relating to the wastegate control.

Dave


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