Funky_Monkey323

Hi guys & Gals

I need help. I know this subject is probabley the most common one in the tech area but it's stumped me completly.

I have an MY96 with k&n full de-cat, VTA dump valve and dawes. I have autometer boost and AFR gauge on board.

One lovely cold night in January I was travelling home and decided to overtake planting the right foot in 5th at about 3500 rpm, over boost occured a couple of times in succesion so I backed off, just putting it down to extremley cold air raising the boost pressure slightly. Ever since then the boost has retarded to 10 psi as apposed to 15psi with the dawes fitted and 7 psi with the dawes removed.

I removed the dawes as I've said to check whether it was blocked but it has made no difference. So I connected the necessary connectors to check for a fault code. There isn't any code detectable the CEL light flashes correctly ( I think ). So I've played the elimination game.

I've checked and changed the the restrictor pipe between the turbo nipple and the actuator.

I've checked, cleaned and changed the boost solenoid, changed the pressure exchange solenoid.

I've checked and changed the actuator, i've checked and cleaned the MAF sensor, I've recently changed the oil and inspected the breather system but it doesn't seem overly dirty, and now I've run out of idea's.

I've previously popsted a question which gave me a few clues but the last reply to my message was very sarcky and said maybe I should try changing gear.

Well that didn't help either cos I tried it!!!!!

Any help would be appreciated as I 've run out of ideas

Regards and thanks in advance

Ed

easyrider

Have you checked the intercooler pipes,wastegate,dumpvalve.

It doesnt sound like it could be anything to do with the boost solenoid/ pipework,as its still low boost with the dawes connected(no ecu control of the boost)

Funky_Monkey323

Sorry should have mentioned that earlier, I have checked all the pipework for leaks.

I connected the turbo and actuator directly without the restrictor and blocked off the pipe to the boost valve,and the boost remained the same so the actuator is working I believe.

If i'm right in thinking the problem is that with dawes connected i don't think it's bleeding the boost away quick enough thus leading to the wastegate opening to early and not allowing the turbo to spool up enough.

Would that also be the case if the restrictor was shot??

This is really confusing and i'm stuck for idea's, i'm currently trying to clean the dawes and check that the bleed hole is not blocked.

Can anybody tell me what the benefit is of drilling the bleed hole slightly bigger to 1 or 1.5 mm??

Thanks again

Ed

easyrider

It may be that the Dawes's ball isnt seating properly and allowing pressure through before its supposed to open up.
A quick,but not recommended way of testing the wastegate is to disconnect the actuator and block the hose go for a brief spin up the road and see if the boost rises up high then-but be very careful not to put the boost through the roof and blow somthing.If the boost does rise properly then the wastegate is o.k-if it still only reaches below your normal dawes setting ,then the wastegate is letting by.

easy

Funky_Monkey323

easyrider

Will this method destroy anything if I drive gently???

I tried to blow down the dwaes in the proper direction and could I could feel air coming out of the other end, so I took it apart and cleaned the ball bearing with brake cleaner put it back together and tried again, this time with all my puff I couldn't get air out of the other end.

I even gave it to one of my girlfriends little brothers who is normally full of hot air and he coouldn't succeed either, am about to put it back and try again.

Hopefully this will cure it!!!! If it does then my original restrictor pipe must be shot through!!!

Ed

easyrider

Id try the dawes back on the car now youve cleaned it out-sounds like it was letting by.
Dont try the wastegate thing unless you need to.You should be able to control the boost level with the throttle-but go very,very gently to start with so it doesnt bring all the boost in at once.

easy

Rourkey

Sorry for butting in folks but im experiencing the same sort of problem in my my93 wrx, i dont run it in the winter month's due to the weather realie, but two week's ago i brought it back out and every time i bring it on to full boost it hit's a bar, spikes and hit's the fuel cut but as it hit's the fuel cut it make's a strange noise like a cow moo once ?
It done the same thing this time last year but stopped it a couple of day's later, i put it down to such cold weather conditions. The only change's to the car other than the full decat exhaust and air filter are: samco boost hoses, new silicon vacum hosing from the waste gate solonoid etc and a bailley dump valve. Every thing seam's fine, no vacum leak's and no fault code's on the ecu and i have swaped and cleaned the solonoid out.
Took the motor to Falkland performance in glenrothes (sco) and they think the car is pretty drab until it comes rite on to full boost, then spikes and shut's down, possible fault's they think are, a cracked compressor housing on the turbo or a sticky waste gate. Im puzzled, they are 2 hrs drive away and think they will need to take the turbo off and leave the motor with them for a week, not too handy for me.
Any idea's would be greatly appreciated, Paul

Funky_Monkey323

cracked it guy's thanks very much for the help.

Upon stripping the Dawes down I found that there was a big lump of crap stuck to the ball bearing stopping it from seating, cleaned it reset it and it works fine.

One thing I did notice was that since i've changed the actuator for one from a MY99 is the scrap yard the car seems to be totally different. The boost is so much more aggressive and that's not because I've been driving it with reduced boost either.

The codes on the actuator vary by 10 digits higher at the end. My original one ending in 20 and the new one ending in 30, they are set up the same as far as I can tell, i've checked the length on the arm and it's identical, very strange but very pleasent at the same time.

As for the other problem from our friend, whose posted above me, I'm not sure what that is. The strange noise could be an induction noise as air get sucked through the filter and tubing, it could be the wastegate diaphram not doing it's job properly and opening the wastegate which would overload the soleniod, or it could be an mapping problem

Have you tried resetting the ecu?? May not make a difference but it's one less thing on the list to eliminate.

Hope this has been some help

Ed

easyrider

Glad thats all it was--it proves that its always best to check the easy things before going into depth.

easy

chrismc

Funky Monkey,

Think I may have a problem with my wastegate, where did you get yours? Only problem with fitting I can see is getting the heatshield off? Couple of the bolts are difficult to get to. How did you find it?

Chris

Funky_Monkey323

Chris

Before you start taking the wastegate and heat shield off what problems are you having?? What are the symptoms, and can you tell me the model year and what mods you have.

It's unusual IMO that the wastegate would go unless it's roasted!!!

Ed