skorpion725

Ok. So in the last year and a half this is what I've been through. New zzp catted downpipe, new k&n short ram intake, injen charge pipe. No issues. Then I got a dyno tune last summer. Soon after started getting cel lights for no apparent reason that would come on and off from time to time. 6 months ago I started getting random misfires and the problem persisted. I was getting codes for sensor 1 low bank, maf sensor, misfires in cylinder 1, 2 and random cylinders. 3 months later my turbo died. Replaced the turbo myself and took it to the dealer to confirm I put it on right, they confirmed it was done correctly, yet didn't even realize that I STILL had misfires and gave me a bill of $400. I've replaced coils and plugs since and still hasn't seemed to make much of a difference. I can drive my car and it's fine and then other times it misses so bad it won't let me accelerate. I'm so confused and NOBODY, not the dealer or any of the several mechanics I know have any idea. Please, if you've had similar problems or have any ideas please help me. People keep suggesting injectors, but on a car with less than 65, 000 miles, I find it about as likely that all four injectors are bad as I did think all four coils were bad. Thanks, Brian

skorpion725

Oh, before the turbo went out I replaced the MAF sensor also. And lately the codes I'm getting are basically the same. I'm getting maf, sensor 1 low bank, all cylinders are misfiring, and baro sensor

umrdyldo

iTrader: (1)

Can you please give us the exact codes you are having?

skorpion725

ok so even though I thought I felt misfires...it's not giving misfire codes. But since I've changed the coils/ plugs, I haven't gotten any misfire codes, yet new codes. Here's what my scanner shows.

misfire mon ok
fuel monitor ok
comp component ok
catalyst component ok
htd catalyst n/a
evap system mon inc
sec air system n/a
a/c refrig mon n/a
oxygen sensor ok
oxygen sensor htr ok
EGR/VVT sys mon n/a

P0451 ENG
evaporative emission system pressure sensor/switch
range/performance
current history MIL

P013E ENG
sensor delayed response - rich to lean (bank 1 sensor 2)
current

P0101 ENG
mass or volume air flow A circuit
range/performance
intermittent

P0106 ENG
manifold absolute pressure/barometric pressure sensor
range/performance
history MIL

P0106 MOD $00
manifold absolute pressure/barometric pressure sensor
range/performance
confirmed

P0451 MOD $00
evaporative emission system pressure sensor/switch
range/performance
confirmed

P013E MOD $00
sensor delayed response - rich to lean (bank 1 sensor 2)
pending

P0451 MOD $00
evaporative emission system pressure sensor/switch
range/performance
pending

P0101
mass or volume air flow A circuit
range/performance
pending

ECaulk

iTrader: (6)

Have you tried a boost leak test? P0101 points to a leak

Assuming you're running 93octane with the tune?

skorpion725

Yes I've owned the car for about 3.5 years and have always used premium gas. How do you do a boost leak test?

umrdyldo

iTrader: (1)

I would check the evap purge valve for failure first. That might explain your evap codes.

Disconnected Evap Purge Solenoid = Very Happy LNF - Cobalt SS Network

Here's how to test it.

Here is the link on how to do a boost leak test.
2.0 LNF Engine Boost leak test a stock SS LNF. - Cobalt SS Network

skorpion725

Tried the evap solenoid test and seems to be fine

umrdyldo

iTrader: (1)

I have had 2 fail that passed the blow through test. They were sticking intermittantly.

Also, try bypassing the boost surge tank.

ECaulk

iTrader: (6)

Pick up a cheap borescope and look at your intake valves through the brake booster connection

skorpion725

Ok, so are you saying i should just buy a new evap solenoid? How do I bypass the boost surge tank and what would that do? And what is a borescope? I'm guessing it checks the valves? But how do valves go bad intermittently?

umrdyldo

iTrader: (1)

You have evap codes which almost always says one of the selenoids has gone bad. So for $15 it's a great place to start.

As for bypassing the surge tank. Just go buy 1 ft of 1/4" hose from auto parts store.
connect your boost selenoid directly to the intake manifold as shown in this pic

skorpion725

Cool, but what does this do/ show?

umrdyldo

iTrader: (1)

There is a vacuum/surge tank right under the intake manifold on the passenger side. Sometimes that tank gets cracked and causes boost leaks. Which would give you a P0101 possibly. Just trying to narrow down your issue at this point. Boost leak is usually the answer.

Do you have a way to look at your fuel trims? Torque app or HPTuners? trying to see how close your tune is.

skorpion725

oh ok, yeah i replaced that and all the vacuum lines to it when I changed the turbo. I'm just really blown by this car. I've always treated this car with the best care and it has just sucked the whole time I've had it. I really appreciate all your suggestions/ help so far. I just don't understand these turbo cars, which is the reason for all the questions. I'm spent, I really am.

skorpion725

And I have no idea about the tune. The guy who tuned my car has been no help and won't answer or return my calls

umrdyldo

iTrader: (1)

Yeah well I guess make you need to get a way to log it. I'm guessing you have some tuning issues that could be related.

Cheapest option

Plus the Torque App for Android. That will help you log and erase codes. I'm guessing your fuel trims are bad.

skorpion725

Again, I don't understand. I have a scan tool that I can erase codes with, if that's what you mean. And then I guess I buy this robot check do hicky and run it to see what it says and then get back to you?

skorpion725

I went ahead and bought a purge solenoid. I'll update on that as soon as I get it on.

umrdyldo

iTrader: (1)

Sorry I didn't respond sooner.

The previous link I sent is to a device that plugs into your OB2 port where a normal scanner goes. It's bluetooth and it syncs to your Android phone or tablet. You then get an app called Torque. The app allows you to monitor all sensors on the car. So not only can you check and clear codes with it, but you can see everything your car is doing.

Terminator2

You have bad map sensors and a huge boost leak. Also have a bad purge solenoid. Replace both maps and your purge solenoid and do a boost leak test.

tomj77

iTrader: (2)

This setup is actually not correct, the line to the manifold is only supposed to see vacuum on the solinoid for the solinoid to actually do its purpose properly, needs a one way check valve on that line. I did that and it worked better cause then the solinoid is not also seeing boost where it should only see vac.

umrdyldo

iTrader: (1)

Dang well good to know. I have been running it that way for 75k miles. Probably fail tomorrow.

skorpion725

If I had a boost leak, how would it be an intermittent problem? Just wondering. Maybe I should explain these "what feel like misfires a little better". I'll be driving and then randomly, my car will stutter/stumble on acceleration. Almost like the car is being shaken. Usually it takes 30 minutes or so for the problem to start, the other day i got two minutes away from home and it was stumbling so bad that it wouldn't even let me accelerate. Turned around and it rode shitty the whole way home. Until I got on the road to my house. Put it in second and it would hardly accelerate, put it in third and it accelerated like a bat out of hell like there was nothing wrong with it. So my question is, if this was/ is a boost leak, how would it be leaking intermittently?

skorpion725

I bought this also just now, I'll let you know when I get it. Should get here in 2 days. I also am gonna exchange my maf sensor in case autozone sold me a bad one and the purge solenoid is on the way.