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Wingnut
08-01-2005, 02:02 PM
Hey, Iam having a problem with code 31 (overboost) factory gauge on window post says Im at 15 psi, it will come and go seems to reset itself,but still reading code with reader, also code 13 (O2 sensor) keeps coming up intermitantly. Anyone have any ideas. Thanks. Overall engine running well now that stalling and rough idle problem solved.

Keller
08-01-2005, 05:24 PM
Code 31 does not indicate overboost. It indicates a problem with the wastegate solenoid circuit. See http://www.gnttype.org/maint/malf.html#31

For the O2, see http://www.gnttype.org/maint/malf.html#13

Also, a pillar monted guage is not OEM, but aftermarket. If you did not put it there, you don't know how it is plumbed in. It may be hooked up wrong. I've helped someone who 'couldn't get full boost' before, only to find his boost guage was connected behind a flow restrictor. "Oh...so that is why I keep getting knock and blowing head gaskets." He was actually running 20+ PSI on pump gas...between failures.

Solve the problems, not the symptoms. Something (or ...things) clearly wrong.

Wingnut
08-01-2005, 10:45 PM
Hey Keller, it is delta gate wastegate with adjustable dail inside but I have no problems with blowing head gaskets or such, after you and Ken helped me with the IAC problem I have set up the waste gate and it boosts good and shifts well. In fact its probably running the best it has in 3 years (summer only) And still code 31 comes up. I am currently looking into the routing of the curcuit. I post what I find Thanks for your help again.

Keller
08-02-2005, 12:09 AM
Do you even have the wastegate solenoid?

kenmosher
08-02-2005, 09:51 AM
Since you have a Deltagate and manually adjustable boost, my guess is that there isn't WG solenoid hooked into the harness.

You can either stick on in the harness (and it won't do anything, but the code will go away), or you can get a resistor and stick it in the harness across the terminals so the ECM thinks a WG solenoid is plugged in.

The 31 will come on when you get into boost and the ECM finds out that there is no WG solenoid.

Wingnut
08-13-2005, 09:14 AM
That sounds like an excellent idea to put in a resistor. Ill give that a try.
I havent posted for awhile because Im having a little problem passing emissions I have tried a number of things , had mechanics look at it and that cant give me any suggestions as to what is wrong once I tell them what I have tried. Still idling a little rough, seems to have a miss but runs good at speed and dailed in pretty good as well. have tried brand new O2 sensor, my egr is working fine, timing is good considering it is running very well at speed, the IAC is brand new and set up,TPS set at .44 (again thanks to Keller and Ken). :) I am at a loss for what I need to do. Does the fan delay and lo and high speed relays have any thing to do with ecm control over fuel or spark, because the last person that owned this car cut all the wires and made the fan run all the time,(still tring to get that one fixed).
Will the engine run if the cam sensor is a tooth out?
Emissions test failing at idle both NO and CO and NO at test speed.

Is there a PROM that will help me with emissions? But still I dont think it will help there is a problem here that I still need to find.

This car is a problem child!!!! Thanks for reading any help would be appreciated like always.