Turbo spoolup upon start up

[Craigthenormal]

Hello,

I am new to posting here at dsm. I come to you with a problem that i cannot find simular symptoms to on other threads. the problem is i get the turbo spooling up as soona i turn the car on @ idle its about 0-3 psi boost not vacum, it runs horrible and stalls a lot, @ 1100 rps it is at 3-7 psi, @ 2000 rpm it is 12-14 psi. i will explain firther after i tell you more about the car. if you jsut want the problem skip to the LAST PARAGRAPH
The back ground of tthe car: it was complety stock
Its a 1990 talon tsi awd, i bought the car with a bad head( timing belt broke) I took the old head off, replacing the whole thing, along with the head i replaced water pump, starter, all belts, hedders(stock one).
After the 3rd attempt of timing it we finally got it right, its @ 4-6 degrees before TDC, w/o adjusting the CAS.
About the problem:
When first rebuilt, i had a slight missfire with rpm over 1500 rpm, but the turbo did not spool up until 3-4k rpm range, when at idle then i had a vaccum of 7-9 ( dont know if that was psi or hg, it said 7 on the stock gauge).
The problem came the next day we went to start it and as soon as i turned it on , we heard a winding and i looked at the gauge and we had boost.
All the lines are tight and sealed, turbo is still good, wategate moves. I then replaced the BOV becouse it wasnt functioning after i ran vaccum tests on it. that didnt fix anything. the new BOV vented into the atmosphere, so i didnt have the return line, i forgot to plug the hole.
That solved my problem no more eirly turbo spooling! but as soon as i plugged the hole it started to spool. My next thought it must not be getting enought air, i got the air intake set up, 3" intake pipe, filter, and GM MAF, thikning it was an air obstrubvtion some where in the old box. Installed the new components, boost porblem still there. Then went and replaced enbtire exaust... that didnt need to be done but i wanted a new exaust. it is a 3" apexi, from down pipe to the tip.

After replacing all the parts, intake, exaust, and BOV i still ahve the problem, The Turbo is spooling up at idle and running horribly like only 2 cylinders are firing, it didnt spool when i had the BOV return line cap was off on the intake. please help.... if you can send pictures, if not i'm happy with words. oh yeah i ordered a new boost controller, i didnt know if the stock one was bad could have caused it.

 

[Craigthenormal]

I have installed th boost gauge, it didnt do anything for the boosting problem, i took off the actuator and manually moved the gate when it was running, it had no effect on it. it still spooled to 0 psi/ vac at idle and 3 psi at 1100,..... is my gate bad then? tomarrow i am going to take the turbo off and inspect the gate itself. if there is any other suggestions please post.

 

[crankbender]

Are you getting these readings off the stock boost gauge?

 

[Craigthenormal]

I just installed the Greddy boost gauge today ans i was getting the same readings.

 

[jott5555]

ide say u have some early spool issues. mabey something didnt go right when u redid the head..

 

[slowAWDTSi]

Yea, somethign is defanatly wrong with the head or turbine housing. It somehow is flowing too much air into the turbine blades. Causing them to spin faster than they should be at idle.
If your exaust cam is too far out and for some reason you are running on the rich side, with the waste spark system, it is possible that excess fuel is burning on the way into the exaust manifold and igniting and causeing it to expand close to the turbine housing and spinnign the turbo faster. But it would be the first time ive seen anything like that(very rare) My guess it to check the timing belt again

Dru

 

[JiveMasterT]

this may sound weird, but change your spark plugs... i had similar problems and thats what worked for me. try that first, and then if it doesnt work id say you might have some other internal head problems or something.

 

[Craigthenormal]

i installed new NGK spark plugs, set gap to .030. nothing changed in my problem. I'm taking it in on monday to get worked on. i'll post when i get the results.

 

[crankbender]

It sounds like your exhaust is not firing in the cylinders but maybe in the exhaust manifold. It kinda sounds like it is acting as though you had a stutterbox.

check your spark location.

 

[Craigthenormal]

How do i check for the spark location? oh this may help too i ahve been over looking it, when it does run correctly, i get a knock code when i push it above idle.

 

[GoSpeedRacerGo]

Couldn't it be a BOV problem with the diaprham being stuck shut?

 

[crankbender]

no it shouldn't be the bov.

Wait a second are you sampling the air for the gauge before or after the TB....if after there is no way in hell it is reading right or you are getting a stutterbox effect. In this case your TB is being stuck open.

 

[Craigthenormal]

I replace the BOV lastweek, the stock one was stuck closed but the new one words great, it didn't help the spooling.I have the boost gauge running, off the intercooler pipes,and it is getting the same readings as the the stock boost gauge. well thats if that's the gauge you were talking about. i tried to run the boost gauge off the fuel pressure solenoid but it just redlined its self as soon as i turned it on. if i go and retime it with the exaust cam 1 tooth off to see if it helps would i need to retard it or advance it?

 

[crankbender]

The readings in the IC pipe should be just above ambient at idle. The readings after the TB should be vacume. What do you mean the gauge redlined when you had it hooked to the FP solenoid? It is possible you have that line hooked to the TB incorrectly and that is causing your problems.

 

[Craigthenormal]

I do not have any hoses comming off my throttle body, i took them off useing the taboospeed shop diagram.i reduced tehm to see if i did one of my hoses wrong but it didnt fix it.

I put the boost gauge back between the fuel solenoid and the intake, it worked fine, i think. i also took my ic elbow at the throttle body off and made sure the throttle moved, it did. i tured on the car , with the elbow and intake disconnected it didnt do its spooling at idle, i got the rpm to 2500 and it spooled up, i could hear the whining and the stock boost gauge read 3 psi, the aftermarket one still was reading vacum from the fuel solenoid spot. once again it bogged down and ran like trash. Could i have something clogging up in the intake manifold?

 

[Craigthenormal]

Is there any way that i may need/buy a fuel pressure regulator other than stock, if there is even a stock? It dows run rich.

 

[crankbender]

When you pulled all those vacume hoses how did you cap off the fittings.

It ran like trash because the intake was disconnected. Start it with all the intake in tact and let us know what the 2 gauges are saying (numbers).

 

[Craigthenormal]

The throttle line i capped with a screw iun the hose and screwed the screwin as mak shift caps.

the reading:
With intake on
Idle: 0-2psi (stock gauge) about +.1 hg (greddy)give or take .05
2000 rpm: 6-8 psi (stock) +.3hg(greddy) give or take .05

with intake disconected from ic elbow

idle: 7 psi vacum(stock) and about 400-500 mm hg vacum(greddy)
2000 rpm 8-12 psi vacum(stock) about 5-700 mmm hg vacum(greddy)

 

[Craigthenormal]

With the intake pipe off how am i getting boost readings with the stock gauge? where does the stock boost gauge gets its readings from?... and if my intake is disconected at the ic elbow why would the engine performance be affected by the turbo spooling, the air is not getting directed into the intake?

 

[slowAWDTSi]

I dont know why nobody has brought this up, the stock boost gauge does not show an accurate reading. It has no map sensor to reead off of. It only can guess by how much air is drawn into the intake. So whatever the stock boost gauge says ignore it. Next you should have the Aftermarket gauge tapped off of the line that comes out of the intake manifold , the line that goes to the fuel pressure regulator soleniod. not inbetween the regulator , you want it tapped right after it comes out of the manifold. After you fix all that check it again.
You need to read the beginners guide for modding the DSM. It all sounds like you are just doing things wrong
Not to make fun or anythign like that
Drew

 

[92GVR4#333]

Check your ECU as well. You may have leaking caps.

 

[Craigthenormal]

not trying to sound dumb, but why is it running horrible with or with out the aftermarket boost gauge on, i did install the gauge as the instructions showed on the taboospeedshop page. even without looking at the gauges standing infront of the car's engine bay you can hear the turbo spooling up at idle and running on what sounds like 2 cylinders. how do i go about checking my ecu for leaks?

 

[JiveMasterT]

Originally posted by Craigthenormal
how do i go about checking my ecu for leaks?

*resisiting urge to say something stupid*

your ecu cant leak... its a peice of bread board with stuff on it. its a little computer. its electric. im not sure what he means about leaking caps, but i would run a boost leak check if you havent yet. also, the sound you hear at startup might be some sort of leak in your intake tract, not the turbo. definately worth looking in to.

 

[thejeebus]

Originally posted by JiveMasterT
*resisiting urge to say something stupid*

your ecu cant leak... its a peice of bread board with stuff on it. its a little computer. its electric. im not sure what he means about leaking caps, but i would run a boost leak check if you havent yet. also, the sound you hear at startup might be some sort of leak in your intake tract, not the turbo. definately worth looking in to.

OF COURSE IT CAN LEAK!

Be careful posting suggestions on here unless you are 100% correct. 1st gens are notorious for the caps in the ECU rupturing and damaging the board. You can check it for leaks by visual inspection (have to pull the cover off the ECU though), and/or you can sometimes smell a bad ECU - smells like sulfur. A damaged ECU can cause all kinds of funny problems.

 

[Deadmoans]

Double check the install of the boost gauge, and the other guy is correct, ignore that piece of crap stock boost gauge. I found good directions on roadraceengineering.com. They had great pics for the install.

Also, would not vent the BOV to the atmosphere unless you have the correct mods to do so. Tech article after tech article, and I even talked to several pro shops and they do not recommend this. You actuallly loose horsepower.

All the posts are good advice - but there's always the great satan!!!!!