Sudden loss of HP

[fierce_101]

Here's my story:

On Nov 24th i bought a 2g turbo awd from california. car looked great. very low original miles (68,000). owned by a middle aged woman and always garaged. flew out to get vehicle and drove back to colorado springs where i live. next day took to chrysler dealership for oil change/inspection. (car squeaked for 10-30 seconds on cold start. colder it is longer the squeaking) found a broken stuf on the exhaust manifold and blown gasket. -fixed that. also replaced all belts (not timing though). Car still squeaks at start up for same amount of time.... not sure what it could be now. next day got 4 new tires then drove to alignment place to get it aligned. here's where the problem is.... after car was picked up noticable loss in acceleration and overall feel of car. it is now 12-19-08 and this is what i've done to try to remedy the problem...

-took back to dealer to get checked out. they said clogged cat... run octane boost through a coupla tanks of gas should help.... after 2 tanks nothing so hollowed cat. no noticable improvement although i found it odd that me CEL didn't come on after that.
-replaced stock airbox with highflow airfilter. nothing just louder
-removed bcs restrictor. maybe noticed something but minute
-checked for boost leak. found one! both sides of throttle body and little screw on throttle body. replaced gaskets tightened screw on throttle body. cleaned throttle body. rechecked boost leak seemed good. noticed improvement but still not where it was. havn't boost leak tested since.
-rerouted vacuum tube to just b4 MAS and put on a lil fuel filter to catch oil. didn't expect nething different didn't see nething different
-replaced spark plugs with NGK BPR6ES (i think that's the model) gapped to .028 (have intention of doing wires just havn't yet) noticed no difference

i think that's everything so far. running out if ideas. lookin for help!

symptoms:
-Doesn't seem nearly as fast as it was when i first got it. (previous car cougar v6... i think that was just as fast as my car is now and that was completly stock less HP and ways more.....)
-Rough idle but nothing crazy.

Additional:
-2nd DSM first was a 1g non turbo completly stock and alwasy was just drove it

Thanks in advance! really hopin to have fun with it again!

 

[97GSTAUTO]

Try resetting your ecu that may help.

 

[Butterfinger]

Do you have a after market boost gauge if not get one. Is the turbo boosting? How much?

 

[fierce_101]

I don't know how to reset me ECU? i'll search the forums to figure it out couldn't be that tough.
I do not have an aftermarket boost gauge. i have every intention of getting one. if it helps the stock one hits the top when i really go for it it other than that it floats round the middle
I was thinking the same thing (boost leak) just havn't gotten the time to test again. will do that for sure

 

[boostedinthe843]

unhook your battery for about 5 min then plug it back in. this should reset your ecu

 

[95redturboawd]

Haha you inadvertently did the first things I would have suggested. +1 on boost gauge and another test.

 

[MrBoxx]

The stock boost gauge is completely useless. Until you have an aftermarket boost gauge, don't add a single modification. So the stocker hits the top when you floor it: You could be staying at 10psi, or you could be spiking up to 20. You'd never know the difference.

Redo your boost leak. You should be able to hold 20psi in the system for at least 20-30 seconds. Of course, you should be using your aftermarket boost gauge to properly tell how much pressure is in the system at the manifold.

 

[fierce_101]

Ok. that all sounds like sound advice. i really appreciate it! since everything seems to be leaning towards getting an aftermarket boost gauge and redoing the boost leak test what would u recommend for a less expensive (but decent) boost gauge. i would prefer not to have to order it online ### i hate waiting for stuff! i'd just rather go down to a parts store and buy one

additional: if this topic has been beaten to death i apologize in advance... i didn't research it yet just replied

 

[habitatguy187]

What kind of gas have you been using? And +1 on resetting the battery.

 

[dylnwit]

check your turbo for shaft play while you have the intake off. If it can move up and down very much, then your turbo might be going.

 

[habitatguy187]

check your turbo for shaft play while you have the intake off. If it can move up and down very much, then your turbo might be going.

Up and down movement isn't as bad as in/out movement.

 

[Butterfinger]

I think your local parts store will cary autometer/faze/sunpro I would go with autometer if I was to buy one of the shelf. I'm sure everyone would say something different. And almost all are better then stock.

 

[MrBoxx]

Autometer is a tried and true brand. Any parts store should be able to either stock, or order, an Autometer boost gauge for you.

 

[romeen]

Most likely a boost leak but since this started shortly after the exhaust manifold was removed you might want to check the manifold nuts to make sure they are torqued correctly. It's possible they may have loosened up a bit causing a pre-turbo exhaust leak. If present, this would cause the turbo to spool slower (later onset of boost) and affect turbo performance throughout the rpms.

Specified torque on a 2G is 36lb/ft for the two larger nuts (upper outer studs) and 22lb/ft on the other smaller ones. Don't over tighten, you can strip the threads in the aluminum head.

Like the others have said, get the boost gauge and then do another boost leak test pressurizing the intake to about 20psi.

 

[fierce_101]

ok so i installed the boost gauge. and while i was at it i decided to install a fuel/air ratio gauge on the hope that it would let me know if i have a bad o2 sensor. havn't redone the boost leak test (didn't have time) but will be doing that shortly. after the gauges were installed i took it for a test spin to see what they were saying.

here's the results:

-at idle my vac reads like 15ish. upon deceleration itll go to 20 or 22
-upon WOT the boost will read up to 15 and decline to 10-11 right b4 i shift and then to zero and right back up to 14-15 and repeat
-the fuel/air ratio gauge wasn't reading nething?? the red light on all the way on the lean side would come on when i stepped on it and would flicker at idle?? i have a repair manual and i taped the wire that it said went to the air sensor or whatever. it was the black wire neways and there were 4 to choose from. if i tapped the wrong one lemme know. it's a 95 eagle talon tsi awd.

so until i do a boost leak test again and see if there is play on the turbo and check the tourqe on the exhaust manifold i'm gonna assume that i have a bad o2 sensor. lemme know what u guys think. thnks for all the help!

 

[Detective Coating]

That air/fuel gauge is useless unless its a wideband such as AEM or PLX, which I'm doubting it is.

Your vac should be 20 at idle with everything else stock.

If you have a check engine light you can take it to autozone or wherever and have them read the code for you. It sounds like your 02 sensor could be bad or a pre turbo leak.

 

[crimsondragon]

It's a leak. You shouldn't be idling at 15 inHg unless you're running aftermarket cams. I had a leak once and it dropped my idle vac to 10. My AFRs on the wideband were still normal since the ECU compensated with fuel trims.

 

[fierce_101]

ya i'll be checking boost leak asap. i drive the car everyday so i can't take it apart every day even though i'd like to

i didn't buy the air/fuel ratio to tune or nething i just got it to A. fill a hole in the gauge holder that i got and B. if i hooked it up right and the o2 sensor was good it should at least be jumpin back and forth from rich to lean while i drive it (correct me if i'm wrong that's just my understanding)

so next time i get the chance and now that the boost gauge is installed i'll be doing the boos leak test again.

anybody know for sure what color wire u hook the air/fuel ratio gauge up to? i dunno wanna be replacing nething if i just installed incorrectly?

 

[fierce_101]

ok so just to let any future user's reading the thread know it is not the black wire you tap into it is the white one (if you are runnin the wire to get the read from the o2 sensor in the engine bay and not doing it the much easier way of running it to the ecu). doing so will cause the gauge to oscilate back and forth forever and ever letting u know ## o2 sensor is working at least that's what i wanted to know. so now i will turn my attention on the boost leak that i apparently have due to low vacuum at idle. i will post progress as i have it. thanx everybody!