Boost flashes to 15 then goes back to 13 and stays????

[Dr. Jeckel]

Finally got my boost gauge hooked up and noticed a odd thing. If I floor the car, the boost will shoot up to 15 immediately( I hear a little knock) then right down to 12-13 psi and stay steady for the rest of the time. I have an ATR bleeder valve and have it set at a setting of 12.

My question is what could be causing it to flash to 15 and then go right back down to 12-13 and stay there through the rest of the gears. I was thinking it might be the actuator sticking or the puck. Just shooting in the dark here though.

I would appreciate any info from anybody who has had this problem or knows what it is. Thanks, James

 

[TT/Ameasap]

Boost spike is usually present with bleeder valves. Shortening the hose from the actuator to the valve would help but maybe a little.

Check your puck arm for anything unusual.

All I can think of right now.HTH

Bo

 

[Dr. Jeckel]

Thanks, I'll try and shorten the hose a little.

 

[Danster]

What chip are you using? A Thrasher will do that.

Dannyo

 

[Dr. Jeckel]

It is the stock chip. I plan to put in a thrasher chip as soon as I get my new pump installed. Would it be better to get rid of my bleeder valve and make my actuator adjustable?

 

[TT/Ameasap]

You can keep the bleeder valve and just shorten the hose a bit to see if it cures the spike. Simple things first


Bo

 

[Dr. Jeckel]

Especially since I paid $40 bucks for it....

 

[slimtastic]

in general ive noticed boost spike to be a problem when too small of a waste gate is used for the ammount of boost ran.

 

[Dr. Jeckel]

Well I would hope that a 13 psi would not be to much boost. Shortening the hose didn't help at all. When I get my scanmaster monday i'll know more...then maybe i'll just get an adjustable wastegate and lose the bleeder valve.

 

[slimtastic]

basicly what im trying to say is that either the main hole on your waste gate is cloged, or my guess would be a defective or "slow to react" waste gate actuator.hope this helps.

 

[Dr. Jeckel]

Thanks, i'm thinking about just getting an adjustable wastegate and giving the bleeder valve away. I really don't like the flash at all.

 

[Dr. Jeckel]

Well i put the original Y-hose back on today to try it out with all the new stuff. I floored it and the boost shot to 18-19 psi before I knew it, then POP and the boost gauge didn't work. I checked under the hood and the line had popped off where the small 1/8" line connects to the metal pipe and had oil in it and the pcv and boost lines on the block above the TB were pushed back, but not blown off. They were also real oily. I am replacing the pcv valve today but was just wondering why the boost didn't stop at like 15psi. I didn't think the thrasher chips had more boost in them.
Is the solenoid bad or the wastegate?
I would like to be able to use my car but don't want the next "POP" to be a head gasket.

Anybody have any ideas I need some help!

Thanks, James

 

[Dr. Jeckel]

Can you move the actuator by hand? Because I can't. Not even budge it.

 

[slimtastic]

well with a little bit of effort you should be able to tug the rod to the passenger side of the car. if not i would suggest testing it with pressure out of the car or replace it altogether...personally i would replace it if you cant move it at all.

 

[Dr. Jeckel]

I think i'm going to order a new one today. I put the stock chip back in it last night and tried it again and the same thing. Just going to half throttle and building boost it will shoot up to 16 then kick down. I think i'll check the puck as well. Thanks for the advice.
James

 

[Dr. Jeckel]

Well i went out this morning and tried pulling the rod on the wastegate and was able to with noticable resistence. There was oil around the actuator where the rod comes out. I ordered an adjustable one anyway so maybe that will fix it. Does anyone have any other ideas to why the boost just want to keep going?
Thanks, James


The quest to get this car to run right just keeps going