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View Full Version : Trying to AutoVe but car wont run without MAF


Darkness
July 3rd, 2006, 02:35 AM
I'm trying to do the AutoVE as per the tutorial but the car will start rough for about 5-10 seconds and then just dies right away and it wont start again period.

I tried all the parameters to see which one was causing this and when its when I set the MAF fail frequencies. All the other steps are done and the car runs good but it doesnt run without the MAF why is this?

The car is running open loop but not SD because of the MAF.

Also, the car has the following codes right now:
P1518 "Throttle Actuator Control (TAC) Module Serial Data Circuit"
P0108 "Manifold Absolute Pressure (MAP) Sensor Circuit High"

Could this be the causing problem? These codes only poped up after I started using EFILive and I dont know what it really means.

:help2:
Thanks
BACKinBLACK
July 3rd, 2006, 12:45 PM
Well im going through the same thing as you right now. I just tried to autoVE my car and it wont run worth a $hit in SD either so no tuning for me, now i dunno where to start. If ya figure it out lemme know and ill do the same
dc_justin
July 3rd, 2006, 12:55 PM
I think that P0108 could be causing your problem. If the MAF is disabled and your MAP sensor is throwing a fault code, then I don't know what your PCM would be using to figure out fueling.

Get the MAP problem fixed and take it from there.
Darkness
July 3rd, 2006, 02:33 PM
I think that P0108 could be causing your problem. If the MAF is disabled and your MAP sensor is throwing a fault code, then I don't know what your PCM would be using to figure out fueling.

Get the MAP problem fixed and take it from there.
I just dont know why the MAP is throwing a code because when I log it it reads fine! I really dont know what that code is doing there though.
GMPX
July 3rd, 2006, 03:05 PM
Well, strange indeed if there is no actual issue with the MAP, problem is with no MAF and a 'faulty' MAP the PCM is just using a default MAP value, hence it don't really run so good (at all).

Did you mess with the MAP scaling at all?

Cheers,
Ross
Black02SS
July 3rd, 2006, 03:39 PM
If you can host up your tunes I will take a look and see if anything looks funky.
Darkness
July 3rd, 2006, 03:58 PM
Did you mess with the MAP scaling at all?

Cheers,
Ross
No, I wouldnt even know where to do that! lol

If you can host up your tunes I will take a look and see if anything looks funky.
Thanks for the offer, I can email it to you, but I dont know where to host it.
Black02SS
July 3rd, 2006, 06:16 PM
email it to black02ss at gmail dot com please. :)
Darkness
July 4th, 2006, 02:44 AM
I found that the MAP only reads 29.2-29.4 kpa, this has to be it, now where the heck is it?
GMPX
July 4th, 2006, 02:47 AM
C6301, Engine Diag, MAP, Parameters.
What MAP sensor is it running?, if it is still a factory 1bar sensor then make sure that is set to 94.4

Cheers,
Ross
Darkness
July 4th, 2006, 07:25 AM
C6301, Engine Diag, MAP, Parameters.
What MAP sensor is it running?, if it is still a factory 1bar sensor then make sure that is set to 94.4

Cheers,
Ross
Thanks, I believe its the factory one, its a delco unit. But this one is hooked up through a vacum hose and is hanging just behind the right valve couver. Shouldn't in be plugged directly to the intake? I blew on the little hose and it seems like it has a crack somewhere. I just cant see it, I think I might have to take off the intake to get it fixed up! ugggrh
Black02SS
July 4th, 2006, 07:28 AM
Yes, it should be on the very back of it. You might be able to get your hand in there and physically put it back. If you find this happening again, you might want to put some silicone around the sensor to hold it in place.
jfpilla
July 4th, 2006, 08:01 AM
http://forums.corvetteforum.com/showthread.php?t=1371948&highlight=map+sensor

You can see it at this link.
98SS2836
July 4th, 2006, 10:39 AM
Take all the coils off the passenger side. Reach your hand around were it should be right in back of the in take. Try to feel what some other "person" did to the intake they had to block the hole or thread somthing in to it. Hope to god they didn't ruin it. Plop the sensor back in the hole and connect the connector its tight fit with the arm but it can be done with out pulling the intake. Pulling the intake off takes about 10 to 15min if you have done it before.
Darkness
July 4th, 2006, 02:27 PM
Thanks for the replies guys. The MAP sensor is not connected directly to the intake (FAST) its connected to a rubber hose and the hose is what's connected to the back of the manifold!!! I dont know who did that but it sure looks "bubba work"
TAQuickness
July 4th, 2006, 04:34 PM
Ah bubba.
jfpilla
July 5th, 2006, 09:38 AM
Thanks for the replies guys. The MAP sensor is not connected directly to the intake (FAST) its connected to a rubber hose and the hose is what's connected to the back of the manifold!!! I dont know who did that but it sure looks "bubba work"

Bubba may know what he's doing. The Map sensor has a tendency to hit the cowl on C5's. Mine is "Bubbad" and works fine:D . There should be an elbow going into the manifold, be sure it's sealed and the rubber grommet in the manifold needs to be in good shape.
Darkness
July 5th, 2006, 10:03 AM
Bubba may know what he's doing. The Map sensor has a tendency to hit the cowl on C5's. Mine is "Bubbad" and works fine:D . There should be an elbow going into the manifold, be sure it's sealed and the rubber grommet in the manifold need to be in good shape.
Yeah I think thats where the vacum leak is, at the elbow, I'm just gonna take the manifold off and do it right.