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Radix problem... Any ideas?

6

67Bird

Full Member
Joined
Jan 10, 2004
Messages
36
Hi,
    I just installed a new Radix and it won't start. It shuts down as soon as the engine fires. Any ideas?

It's a 2004 5.3... I double checked the wiring and the fuel pump was installed and tested prior to the supercharger install. It doesn't throw any codes or check engine lights.

I'm clueless now...

Thanks...
 
don't have a fuel pressure guage on it... I'll need to get one to check.
 
Did you reflash the PCM with the Magnuson supplied tune?

Can you hear the fuel pump run for a few seconds at key-on?  Intercooler pump should do the same.
 
DrX said:
Did you reflash the PCM with the Magnuson supplied tune?

Can you hear the fuel pump run for a few seconds at key-on?? Intercooler pump should do the same.
Click to expand...

Yes I reflashed the PCM... was thinking about putting the stock tune back int to see if it will idle.

I hear the fuel pump cycle... But I'll need to have some one else try it and listen to the intercooler pump.

Thanks for all the ideas... Still looking...

Seems to me like something simple since it actually fires just shuts off imediately after starting... even if the key is held in the starting position... So that leads me to believe the computer is shutting it down.

 
Have someone watch under the hood to see if the vacuum actuated bypass valve is opening upon start up. Maybe it's stuck closed and the vacuum isn't capable of opening it like it is supposed to when it is started. Normally it is in the closed position when the engine is off and opens when vacuum is created behind the throttle body. It's located on the side toward the rear of your supercharger probably opposite of where the throttle body is.

Edit:
Here's a pic of it on my Magnacharger. Mine is on the front due to my blower being mounted backwards on my GTO.

 

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onyx_z71 said:
Edit:
Here's a pic of it on my Magnacharger. Mine is on the front due to my blower being mounted backwards on my GTO.
Click to expand...

Sorry for the  :jacked: but that GTO's got to really move with the Magnacharger!
 
MyBigToy said:
Sorry for the? :jacked: but that GTO's got to really move with the Magnacharger!
Click to expand...

It does go pretty well. I love the sleeper look of this car. Imagine the look on a guy with his new Viper having his hands full on the e-way against a car that he probably doesn't even know what it is. LOL!

I've since installed a set of Kooks 1 7/8" Jet Hot ceramic coated long tubes and I had a safe tune done to it on a very unforgiving loaded Mustang dyno and it put down mid 400's to the ground only with pump gas, and these GTO's loose a lot of power through the driveline due to the IRS and 2 piece drive shaft with rubber couplers instead of universals. Bone stock auto cars have posted 80hp driveline losses from the rated 400hp at the flywheel. At WOT, my car will begin to get traction late in 2nd gear, and the tires will spin straight through the 1-2 shift.

I'm currently working on traction issues, and if I can get the car to hook up, I'll probably throw a 3k stall in it and shoot for mid 11's. I haven't had it at the track yet, but I'd expect a low 12 the way it is. It's difficult to get wide tires under these cars without really modding it for clearance. I have done some suspension stuff (rear springs, urethane components), but I still need wider tires.

I like the instant boost at any RPM and the factory appearance of the completed install. There are a lot of reputable FI kits offered for these GTO's, but I decided on the Maggie over all the others as I truely believe it to last the life of the car and not take much if any away from the longevity of the engine. Magnuson has made a ton of GTO kits and all 3 of their different blowers are offered for the GTO. Mine is the base 112H. They offer the 112HH and the 122HH for it now too.

Here's a pic of my completed install. I just left the engine covers off.

maggie.jpg
 
67Bird said:
Yes I reflashed the PCM... was thinking about putting the stock tune back int to see if it will idle.

I hear the fuel pump cycle... But I'll need to have some one else try it and listen to the intercooler pump.

Thanks for all the ideas... Still looking...

Seems to me like something simple since it actually fires just shuts off imediately after starting... even if the key is held in the starting position... So that leads me to believe the computer is shutting it down.
Click to expand...

It might idle with the stock tune,  but barely because of the lager injectors.  It will be very rich.

Might try uninstalling and re-installing the Mag tune.

edit: moved reply outside quote
 

Might try uninstalling and re-installing the Mag tune.? +1

(y)

One very common occurence that happens on install that I have read about alot is the O-ring getting damaged on the fuel pressure regulator as well when it is installed, not sure if it would cause the problem you see, but if it's not getting the proper fuel... it would be an easy check..

d
 
DanV said:
Might try uninstalling and re-installing the Mag tune.? +1

(y)

One very common occurence that happens on install that I have read about alot is the O-ring getting damaged on the fuel pressure regulator as well when it is installed, not sure if it would cause the problem you see, but if it's not getting the proper fuel... it would be an easy check..

d
Click to expand...

That was my first thought, but it is an 04(returnless) so there is no FPR on the rail.
 
Thanks for all the info...

I'll check out the actuator for movement.

My first thought was fuel or vacuum too. What keeps bugging me is it turns over seems to start then shuts off even with the key in the start position?! So it's not like it is just cranking because of no fuel.

My next thought was the theft deterant system... That's exactly what it acts like.

I just tried uninstalling and re-installing the manuson tune and I got the same results... I also went over the plugs and connections again and don't see anything off or loose.

I think I'm stuck at this point until Monday... I just hope I don't need to pull this thing back off.

Again thanks for all the ideas...

Tom
 
Seems like a tune issue if no codes are being set.  Did you check with a code reader? Did you try starting it with the original tune flashed back in?  It should at least run a little longer that way.  If so, then I would suspect the supplied tune/OS is not correct.  Is this your original factory supplied PCM?
 
yes it's the original stock PCM just reflashed.
I did try to read the codes and nothing comes up.

I'll see if I can flash the factory tune back in and let you know.

Tom
 
Ok tried the stock tune and it cranks but won't fire up. So I  re-installed the mag tune and I got the same results as before. It fires up and shuts down imediately. One thing I found this time is if I hold the key in the start position is after it shuts down a few seconds later it refires and shuts down again. It will keep doing that if I keep holding the key in the start position... kind of odd I thought...

I have tried a couple ways of unlocking the security incase it was tripped. none of them have worked though.

Going to get a fuel preasure guage today to check at the fuel rails. I'm also going to go over all the connections again today to verify again before talking to tech suport tomorrow.

This really seemed to be a straight forward install too... I guess I should have just went the duramax crew cab direction instead of the supercharger... :E:
I really love my truck though and didn't want to give it up.
 
Did you ever check the bypass actuator for movement? I think the security has absolutely nothing to do with it myself.

All the Magnacharged cars I've seen including my own sound like they want to stall upon start-up for a split second before catching itself and staying running. It's weird, but the car always starts, and I haven't had any problems with it like you are having with yours.

All I can think that is causing it is the transition from being at boost while cranking, and going to bypass once vacuum is created to open the valve. There simply has to be more air being pulled in at idle before the bypass opens, and that must be causing the split second stumble my car has at start up.

This is why I believe your problem lies in the bypass and it is not opening at all or fast enough for the fuel injectors to catch it. You may also want to make sure all the injectors are plugged into the harness properly. Perhaps you have a couple injectors crossed in the wiring harness.
 
Sorry onyx_z71... I thought I posted the bypass results but I didn't.

Yes the bypass opens as soon as it starts then slowly closes again after it shuts down. Not sure if it is as fast as it should since I never seen one working in person.

I checked all my connections again this morning and will verify all the injectors are connected properly and tight again.

So far today I tested for spark and verified fuel is in the fuel rails... I'll get the fuel gauge later today to see what the pressure is.

If I have good fuel preassure and spark I think I can rule out the fuel pump and security system... That only leaves the PCM and/or the Tuning. I guess I'm surprised it didn't at least start and idle with the stock tune in it. Should it have?

Do you think maybe my PCM got scrambled by the flashpaq?!



 
67Bird said:
I guess I'm surprised it didn't at least start and idle with the stock tune in it. Should it have?
Click to expand...

I believe that mine started with the stock tune but didn't run too well.

67Bird said:
Do you think maybe my PCM got scrambled by the flashpaq?! 
Click to expand...

Possible if there was a loose connection or battery voltage fell too low.  But the flash process likely would not have completed. 

A call to tech support is in order if your fuel pressure and wiring check out OK.


 
Tech support should definately get it resolved...but, my money is on the security system...have you tried to start it like 5-6 times in a row (one right after another)...I had this issue (it was a while ago, and I don't remember what else was the problem), but, on like the 4th or 5th attempt, it would run. then on like every 3rd time i had to start it, I would have to go through 4 or 5 cycles again before it would run.
Good luck!
 
I hope you get it figured out. I want to put one on mine.

Sam
 
Just did the fuel pressure check and I have 45 lbs. when the pump cycles on and 58 lbs. when it is trying to start... Does that sound about right?

Sam go for it... Don't let my horrible luck discourage you. Just to give you an idea of my luck the day I started this install my wifes Subaru outback blew a head gasket... So it's not the product it's me :)
 
58 psi sounds good.  So I have to agree with BBAv. 

Did a little reading today.  If the PCM has lost the learned password that is sent by the BCM at startup, the injectors will be disabled by VTD. 

Did kinda sound like my EFILive programmed kill switch that cuts fuel.  I have it set to cut out at 500 RPM.  I initially had it set a little higher so potential thieves could barely roll bucking all the way.  But that would only be funny until they intentionally crashed my AV.

Anyway, here is the backyard relearn procedure copied from the manual.  Follow it exactly:

30 Minute Learn Procedure

Turn ON the ignition, with the engine OFF.
Attempt to start the engine, then release the key to ON; the vehicle will not start.
Observe the SECURITY telltale; after approximately 10 minutes the telltale will turn OFF.
Turn OFF the ignition, and wait 5 seconds.
Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes; the vehicle is now ready to relearn the Passlock Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.

Important
The vehicle learns the Passlock Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.


Start the engine. The vehicle has now learned the Passlock Sensor Data Code and/or password.
With a scan tool, clear any DTCs, if needed. History DTCs will self clear after 100 ignition cycles.
 
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