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Possible GEMS issue

Lashcat

Pro
Joined
Mar 28, 2010
Messages
175
Location
North Pole, Alaska
I have a Phazer that I supercharged (MPI). I can't get fire or fuel. I am beginning to think the GEMS controller has gone bad.
1. Has anyone else had this issue?

2. Can I switch from GEMS to Power Commander?

3. How much of a pain is it to switch it over and get it mapped?
 

I have a Phazer that I supercharged (MPI). I can't get fire or fuel. I am beginning to think the GEMS controller has gone bad.
1. Has anyone else had this issue?

2. Can I switch from GEMS to Power Commander?

3. How much of a pain is it to switch it over and get it mapped?

Pully the Belt on the Supercharger, unplug the Gems and plug it back as stock, will it start now?
 
I disconnected the Gems. No joy. I was able to get it to back fire once. But It did that with the Gems when it first failed to start last year. It has new plugs in it. I have the air box off and I sprayed starting fluid into it and it still does not start.
 
I disconnected the Gems. No joy. I was able to get it to back fire once. But It did that with the Gems when it first failed to start last year. It has new plugs in it. I have the air box off and I sprayed starting fluid into it and it still does not start.

at least now you can rule out the gems being the problem.
 
Yes. I set the gauge pod to diagnostic. So far nothing conclusive, but I have not finished checking everything listed. I will continue to update as I check things out.
 
Diagnostic code results:
01 Throttle angle fully closed 15 - 18 (15) fully open 96 -100 (41)
03 Pressure difference (atmospheric pressure and cylinder-#1 intake air pressure (97)
04 Pressure difference (atmospheric pressure and cylinder-#2 intake air pressure (96)
09 Battery Voltage (12.5)
24 Throttle switch on - off (tested good)
30 Cylinder-#1 ignition coil (?) It back fired again while testing #1 but the code 00
31 Cylinder-#2 ignition coil (?) Indicates 00
36 Injector #1 ( clicks when cycled on)
37 Injector #2 (click when cycled on)
50 Fuel injector relay (cycles)
51 Fan relay ( operates)
60 EEPROM fault code display (no fault displayed)
 
I have fuel at the fuel rail, I took the rail loose and I had fuel at the injectors. I don't know what the pressure is yet. I have good flow from the pump. Once I get home I will pull the tank so I can check the spark.
 
Put new plugs in. the arch was yellow coming off the plug but blue where it hit the head. Charging battery up now. No joy.

Drop some new plugs in for sure.. now you need to make sure you have fuel. Pull the line and see if its pumping?
 
I tested the compression. I did a dry test and got about 70 psi on each cylinder. After dumping a little oil in each i am getting 117 and 118 on the cylinders.

New plugs are installed. Disconnected the fuel line at the fuel rail and I have good flow.
 
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Well the wild goose chase is over. It has low compression on both cylinders. I am getting about 70 psi on each cylinder. Now to take it apart and see what caused it.

At least you made headway.. not what you wanted to hear I bet.
 
No kidding. I am going to empty the fuel tank and put fresh gas in and see what happens. I doubt it will change anything but at least I will have checked it off the list.
 
I just went back and re checked the fire. I pulled the plugs, they are clean and dry. Sniff test results, it smells like they have been firing. Each plug inserted into the coil pack and hit the start. both have fire. I pulled the pugs out of the coil packs and used a circuit tester to see how far the spark will jump. Cylinder one seems stronger than cylinder 2. But this is just using sight. I am not happy with either cylinder. I am going the look more into the ignition system.
 
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I just went back and re checked the fire. I pulled the plugs, they are clean and dry. Sniff test results, it smells like they have been firing. Each plug inserted into the coil pack and hit the start. both have fire. I pulled the pugs out of the coil packs and used a circuit tester to see how far the spark will jump. Cylinder one seems stronger than cylinder 2. But this is just using sight.

Squirt a cap of fuel in each cylinder and see if u can get any kind of fire. Can you hear fuel pump when you turn the sled to on?
 


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