Resolved 2G MPI relay does not click

[talontsi98]

Got no spark. The mpi relay does not click when you try to start the car. I have thried using a good relay and no luck. Any ideas?

 

[ShawnsGarage]

Do you get a Check Engine Light for 5 sec. when you turn the key on without trying to start the motor?

 

[talontsi98]

No engine light on startup. What does that mean?

 

[ShawnsGarage]

Don't try to start the motor. Just turn the key forward 2 clicks and watch for CEL. If you don't get one your ECU is not booting. Are you sure the MPI relay you swapped in is any good?

 

[talontsi98]

It worked fine in my gsx.

 

[steve]

So your question isn't for your car? Please tell us what it is for.

I haven't seen many MPI relays fail. It's usually the fuse or the ECU that bad unless people are hacking on the wiring installing alarms or turbo timers. I guess I should say installing or have aftermarket alarms or turbo timers since the average install quality is low and they quit working because of it.

A couple of mins with a voltmeter will narrow the problem down. Do you have the wiring diagram?

 

[talontsi98]

Its for my 97 gst. What fuse are you talking about. And yes I have an ecu pinout diagram.

 

[talontsi98]

Did a voltage test on relay at green pin 38 for power and red pin 13 for ground and got o.o- 0.2 volts. Also did a resistance test and got ol or open. Does it supposed to have source voltage?

 

[steve]

Pin 38 should have 12v on it when the ECU is off and next to 0 volts when the ignition switch is on.

Pin 13 and 26 is a black wire for ground, not red. The red wire on pin 12 and 25 is the switched power from the MPI relay and should have 12v on it when the ignition switch is on.

Pin 80 is a red with blue stripe for the constant "backup" power and should have 12v all the time.

Pin 82 is the signal from the ignition switch that goes to 12v when you turn on the car (Run or Start positions). It what the ECU is looking for to turn on the MPI relay.

http://www.dsmlink.com/images/forums/2GECUPinout.pdf
http://www.dsmlink.com/images/forums/2GECUMFI.pdf

 

[talontsi98]

Got the electrical test results below.

Pin 38 had 0.007 volts

Pin 12 and 25 had 0.009 volts

Pin 80 had source voltage

Pin 82 had source voltage

What is the next step? A fuse?

 

[steve]

The next steps would be to look at the power to the MPI relay and to test the relay itself.

The relay test procedure is simple. Apply battery voltage across the relay coil and check that the contacts close.
On most of the DSM MPI relays the power input and one side of the coil share a pin so if your does then you would be looking to see if the output goes to battery voltage when you activate the coil.

 

[talontsi98]

Power to relay at start position is 0.013 volts and 0.000 to 0.001 volts at off position. I have tested a known good relay.

 

[steve]

I think you have found the problem now you just have to find the cause.
As you can see from the wiring diagram the power comes from the MPI fuse. If the wire was shorted it would be popping the fuses as soon as you plug them in.

 

[talontsi98]

Found the problem. The 20 amp fusible link was defective. Replaced it and it fired up. Thanks for all of you help.

 

[slayndragn]

please let me know where i can get mpi relay online mine actually went bad car was sitting and it rusted

 

[steve]

please let me know where i can get mpi relay online mine actually went bad car was sitting and it rusted

You have to fix your profile before we know how to help. There are different versions of the "MPI" relay depending on the year car.

However the classifieds would be a good place to start by looking for people parting their cars.

 

[slayndragn]

it's for an evo 3 and can use the same one as the 95 gst turbo you dont know a prts dealer that i can order it from over the internet? i live in the cayman islands and i'm not having anyluck finding one here

 

[steve]

For the right price I'll deliver it. I had a great time the last time I was there. That Georgetown is not in PA.

Is is a single gold box E8T08474 or the gold box E8T07071?

The 95 E8T08474 is MR161519.
The 1G E8T07071 is MD119202.

The later 2 black relay from the 96+ 2G's is MR224160.

 

[slayndragn]

like i said its for an evo it's gold and has 8 wires rather than 9 that is in the earlier dsm models....im originally from philly relocated to the cayman islands would gladly pay for one to be shipped (grand cayman Cayman islands) do u use paypal?