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Car wont start after de-mod.

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Old Oct 22, 2008 | 11:02 PM
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Default Car wont start after de-mod.

Hey guys. I have had two of the most frustrating weeks ever. I just finished de-modding my 200 GTO. I took off heads, cam and headers and put it back to stock. The only difference is that the stock cam is advanced 4* from the previous setup. Also the car was initally tuned in SD. I got a stock 2004 GTO tune and loaded that as well.

The car turns over but will not fire up.

I am getting fuel.
The packs show spark.
There are no codes.
I checked all the grounds and everything is connected. Two on the front passenger head and two on the back of driver side head.

I have absolutely no idea whats wrong. I did a log with HP Tuners of the startup and its showing 13* advance on startup. This is my first time using HP so I dont know if thats normal, especially with the 4* advanc on the stock cam.

I need serious help. This is my only car and I am moving in a little over a week and I need my car up and running.
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Old Oct 23, 2008 | 12:26 AM
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Sorry bro, i cant help much but why are did you de-mod the car?
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Old Oct 23, 2008 | 12:47 AM
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Im selling it.
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Old Oct 25, 2008 | 09:08 AM
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Bump for help.
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Old Oct 25, 2008 | 03:03 PM
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try adjusting the timing with hp. Also did you make sure the mechanical timing was set correctly?
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Old Oct 25, 2008 | 03:49 PM
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do you see engine seed?
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Old Oct 25, 2008 | 03:49 PM
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speed sorry
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Old Oct 25, 2008 | 03:49 PM
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it might have something to do with your sd tune before.check that again.
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Old Oct 25, 2008 | 04:29 PM
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Yes it shows engine speed. The timing hain was also dont corectly. I aligned the dot with the 0. Im thinking it may be the SD tune. But I did load the stoc tune back in but the MAF is still dissabled. Didnt help. Today i got new plugs and im going to try that and see if they actually spark. Not just the coil pack.
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Old Oct 25, 2008 | 04:35 PM
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put maf back on and connect it.
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Old Oct 25, 2008 | 07:11 PM
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ya ur gonna need the maf hooked up and hope ur gonna tell its future owner its been demodded
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Old Oct 25, 2008 | 10:10 PM
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Would the maf effect it from starting though ??
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Old Oct 25, 2008 | 11:25 PM
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The maf is connected. But with te SD tune it is tuned off. i dont know how to use HP Tuners to turn it back on. Maybee someone here can give me a quick schooling on that.

On a side note what difference does it make if a car was demodded. Its way past the warranty anyway. Plus its going back to a dealer for a trade in.
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Old Oct 26, 2008 | 01:29 AM
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Originally Posted by Vndcatr
Would the maf effect it from starting though ??
I think it could I think if the readings are f'd enough?? When my maf went bad it just stuck on these funky settings and my car would barely start and run like **** and wouldn't move 2 ft. and knock off. Have you checked the engine fuses under the hood? Not only was my maf bad but it was blowing a fuse too further f'ng things up. I kept thinking it should run alright (open loop) with the maf unplugged but didn't know I had a blown fuse too.

It's a long shot but it only 5 minutes of your time too check.

If you can get reader ( we used a snap on) to see what your maf "sees" that will tell you for sure provided the maf fuse is good. I never knew the maf had a fuse til then silly me Honestly that Snap On was great and could do about everthing a TECH II could
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Old Oct 26, 2008 | 11:03 AM
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If you say youre getting spark and fuel, Maybe you should do a compression check just to be sure?
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Old Oct 26, 2008 | 11:07 AM
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Originally Posted by Oh4GTO
The maf is connected. But with te SD tune it is tuned off. i dont know how to use HP Tuners to turn it back on. Maybee someone here can give me a quick schooling on that.

On a side note what difference does it make if a car was demodded. Its way past the warranty anyway. Plus its going back to a dealer for a trade in.
if its going back to a dealer thats not as bad but i dont know that just seems shady, modding a car and beating on it then demodding it and selling it without a word, just my .02
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Old Oct 26, 2008 | 02:13 PM
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I dont beat on my car. Ive treated it like it was my first born. It was always N/A so it relly wouldnt make a difference if I tacked it out stock or with heads and cam. Plus I would not keep it from anyone.

I did check all the fuses under the hood and inside the car. Like a few here mentioned, it seems the SD tune may be the culprit. Im sending the car to MTI tomorrow so they can do their magic because I am completely out of ideas.
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Old Oct 26, 2008 | 02:49 PM
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sorry i didnt mean to insult or anything, hope u get it running!
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Old Oct 27, 2008 | 01:39 AM
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Put in new spark plugs just for the hell of it. It almost fired up on the first try and then after that it was the same story over again. Sigh.
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Old Oct 28, 2008 | 05:07 AM
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off topic but what are you buying.......
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