Stalling stuttering and CEL PO171

T

TurboMan

Member
:
2003.5 Titanium MSP
I'm the the original owner of an 03.5 MSP. Several months ago, my MSP started stuttering violently every time I go into boost (approx. above 4K RPM). In addition to this, it has an erratic idle, occasionally throws a P0171 CEL, and it dies randomly about once every 1-2 weeks.

I've taken the car to Motorsport Techniques in Hayward, and they seem to think that it may have something to do with the wastegate, but their answer was not definitive.

Has anyone else had a similar experience, and if so, what did you find to be your remedy. Also, does anyone have a good shop recommendation in the Bay Area? I don't have time to do much more than fairly basic tinkering these days and I need to get this problem fixed.

Thanks in advance.
 
Last edited:
TurboMan said:
I'm the the original owner of an 03.5 MSP. Several months ago, my MSP started stuttering violently every time I go into boost (approx. above 4K RPM). In addition to this, it has an erratic idle, occasionally throws a P0171 CEL, and it dies randomly about once every 1-2 weeks.

I've taken the car to Motorsport Techniques in Hayward, and they seem to think that it may have something to do with the wastegate, but their answer was not definitive.

Has anyone else had a similar experience, and if so, what did you find to be your remedy. Also, does anyone have a good shop recommendation in the Bay Area? I don't have time to do much more than fairly basic tinkering these days and I need to get this problem fixed.

Thanks in advance.
Click to expand...

well i had the same code on my car i bought a new atp wg and sensor by you turbo manifold. it worked for me!! try it. atp its only 50bucks and better than the stock one and sensor its so easy to take off.(2thumbs)
 
o2 sensor? disconnect your wideband o2 and see if the problem goes away. Then reconnect it and see if it reappears. If it doesn then your o2 is shot.
 
i say its ur wastegate or atleast start with that and as for cleaning the egr valve that might work but the egr valve might just be ****** and cleaning might not help u might just have to buy a new egr valve and new wastegate go to atpturbo.com
 
What's your vacuum reading at idle and how long has it been since you have changed your spark plugs, pcv and air filter? Depending on your miles your wires and or coil packs could also be shot.

Cleaning an EGR is a waste of time. Frequent seafoam treatments and adding some to your gas tank will prevent it from getting gunked up in the first place.

Pressurize your WGA to see if it moves freely or gets hung up. I mean with compressed air and not the commonly suggested blow with your lung method which isn't going to move anything. P0171 can be for your WGA diaphram being shot but also for a fuel system issue, vacuum leaks and exhaust leaks.

Narrow done the source of the problem before replacing expensive parts for what might be no good reason.
 
someone on this forums said that if you blow into the vacuumline that connects to your WGA and the air is able to flow through then your EGA is shot. If the air cannot go anywhere then it is ok. I checked mine and i am ok!
 
Well it sounds like you might have a leak in one of your intercooler pipes...or even between the MAF and the turbo inlet. If the car acts up under boost it could be a result of a boost leak. If unmetered air is getting in or metered air is leaking out you will have symptoms similar to the ones you have described...it would be a good idea to look for cracks in the pipes or bad vacuum lines....a boost/vacuum gauge will also tell you if you have a leak somewhere...
 
I had the same issue. Put a boost gauge in the car and noticed the inches where way high. Squeezed the line going to the wastegate and it went right to 20 inchs. Replaced it with the $100 wastgate from protege garage and its been mint. Redlines every gear smooth.
 
I too am chasing down a p0171 (poke)

Checked vacume lines, all good. Light came back.

Replaced crack hotpipe. Light came back.

Going to double check WGA tommorrow.

Also doing 1k22 Denso plugs, new wires, and rear 02 since its the og one. my car might be the highest milage MSP here, 140k (attn)

The annoying part is the car still drives fine. Idle is a bit low between 709-698 ( apexi imoni )

p0171, you will be gone!!!!! (flame)
 
Update.

Did a seafoam, smoke from under the manifold cover. Took it off saw two big cracks staring back at me. Removed the 02 sensor, melted bent tip.

Going with steedspeed manifold and have both front and rear 02's waiting.

ALSO put in new wires and Denso 1k22 plugs, motor runs alot smoother, even with a melted 02 lol.

This week, the battle rages on! (chair)
 
Real tipical issue with the MSP. A lot of broken manifolds on the forum. I really with they did a better job with the manifold, I wonder what the issue is. Is it poor quality, to hot from the tiny turbo or something else?
 
My guess at first glance, no releave cuts at the head, no support for the turbo (stress on the header) and poor casting.

At any rate, going with a steedspeed.
(sleep)

Be nice when I get this done and focus on the fun things.

Wheels.
Tires.
Camber.
Slam.
 
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Replaced front and rear 02 sensors, ran even smoothers...for a bit.

Light came back on. Have to check to see if it's the same code. (gossip)

Next guess is the WGA, gonna pick one up, throw it in there.

The ATp SR20 one.

-Paul
 
FIXED THAT s***

Along with everything listed above final fixes were:

Replaced the WGA. What a difference lol Bought the one off PG, 65 bucks.

had a major vaccume leak from a tube off the manifold not plugged into anything.

The lines for the accuator and the BPV were just....bad lol Tee'd and rerouted those with the one from the intake manifold and added a boost gauge.

Car pulls great now.

All you P0171 suck my boost.
(bird)(band)(idhitit)(group)(screwy)(spin)(beer)
 
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