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4-G-rim
04-28-2008, 12:02 PM
Here is the scoop:

Started the car up on Saturday and let it warm up and in about 2 mins the motor just shut off completely..but still had power to everything like normal. Tried and tried to turn the car back on..but the motor will just crank, but won't turn over. Checked a few things and started to diagnose.

Checked for spark...I got spark.
Checked timing and inspected belts thinking of the worse....Timing marks are spot on, tension is perfect, and belts are fine.

Checked for fuel..no fuel, should of realized it as I didn't hear the "whine" of the pump come up on the On position. Did the fuel pump test from the jump wire on the firewall and the pump didn't come on. I unhooked the feed line to the fuel rail and crank the cars a couple of times and no fuel..so I am thinking to pump took a crap.

So I tried one more thing...and go access to the pump. Removed the plug and ran power directly from the GVR4's battery and the pump is running and a nice mess of fuel shoots out from the unhooked feed hose.:smile: I then tried to see if there power coming from the plug to the pump with a test light and with the ignition on the "ON" positiion there is no power.

Now..I have narrowed it down to electrical and thinking its the MPI relay/fuse. My question where is it or is there something else I didn't look at to diag why there is no power getting to the pump?

Stewi
04-28-2008, 04:54 PM
locate the MPI relay and supply power to the terminal that the relay normall powers when activated, if the pump turns on, you have ruled out everything between the relay and the pump. at that point I would say its the relay.

4-G-rim
04-28-2008, 05:43 PM
I can't seem to find where the MPI relay is on the 7g.

DOHCstunr
04-28-2008, 07:05 PM
kevin.

i checked under my hood.
the black conector we were talking about.

there are two of them on mine. and one blue connector and one big round brownish conector.

the brownish one is not the fuel pump check terminal.
niether is the blue if i remmeber correctly.
one of the black ones has two wires. this also is not it.

one black connector has one wire.
black with blue stripe.

this is the one you need to connect to a 12v source.
you may or may not also have turn the ignition switch to the on position.

i checked it myself about 10 minutes ago.

4-G-rim
04-28-2008, 07:09 PM
Hmmm...maybe I missed that connector you are talking about. Let me check it out again right now and see if I can power up the pump.

If I jump this wire and the pump turns on...its the MPI relay thats the problem right, since that test wire bypasses the MPI relay right?

Ok...these are the only plugs "loose" that I can find.
http://img186.imageshack.us/img186/3619/p4200338jx2.jpg
http://img186.imageshack.us/img186/5061/p4200342fl7.jpg

4-G-rim
04-29-2008, 09:01 AM
Not sure if the little silver box just under and behind the ECU is the MPI relay or has anything to do with giving power to the fuel pump. I thought it does and Seth thinks so also..but we are both not 100% sure.

It gets power from the black/green stripe wire all the way on the right terminal of the plug show in the pic. Now I was thinking of jumping a wire to the black/blue stripe wire terminal and see if the supplies power to the plug to the pump. I don't have wiring pin diagrams and hoping maybe here can confirm this is ok to do...I don't want to "F" up something else.

http://img171.imageshack.us/img171/5526/p4200344dl8.jpg

DOHCstunr
04-29-2008, 11:02 AM
the silver box is your power steering controller for the variable assist.

i'll take pics for you kev.

also of the mpi relay.
its in the dash, but, its on the drivers side of the radio bracket.
you'll have to take off the panel thats right where your knee woudl be for your gas pedal foot. to get that panel off you'd have to take the drivers side lower dash off as well.

4-G-rim
04-29-2008, 11:12 AM
Alright..I just got done reinstalling the sender unit back into the tank. Time to go back into the garage and locate this MPI relay. Thank bro. :smile:

BTW: Do my "jump" termianals look different from yours. Maybe there is a difference between the 94-95 to the 96-98's?


***Ok...removed everything the parts you said I had to remove to get the MPI relay. I located what seems to be 2 relays on a bracket that is held on by a 10mm nut. Is this it? Both are labled with the idectical production or part#'s I believe.**

http://img176.imageshack.us/img176/4899/p4200346om7.jpg

4-G-rim
04-29-2008, 07:03 PM
Ok so far no luck on the diag. :sad:

Started looking around and found this relay tucked under the fender apron and didn't find it prior. Is this the MFI relay? There is a red loom plugged to it with 3 10mm bolts holding it to the fender apron.

Here is what I am talking about.
http://img241.imageshack.us/img241/2121/p4210348xc6.jpg

DOHCstunr
04-29-2008, 08:04 PM
Alright..I just got done reinstalling the sender unit back into the tank. Time to go back into the garage and locate this MPI relay. Thank bro. :smile:

BTW: Do my "jump" termianals look different from yours. Maybe there is a difference between the 94-95 to the 96-98's?


***Ok...removed everything the parts you said I had to remove to get the MPI relay. I located what seems to be 2 relays on a bracket that is held on by a 10mm nut. Is this it? Both are labled with the idectical production or part#'s I believe.**

http://img176.imageshack.us/img176/4899/p4200346om7.jpg

thats where my relay is.... but mine is zinc anodized(goldish) and its only one box instead of 2.

i'm going to my car right now to get that picture.
the terminals under the solenoid rack on the firewall are usually taped into the loom. have you untaped all of them for certain?

DOHCstunr
04-29-2008, 08:08 PM
btw is yoru pump rewired? or no....

possible that your cheapy relay is shot.

4-G-rim
04-29-2008, 08:10 PM
Yup John...thats the only plugs that a free on the firewall. I checked throughly to see if I missed anything..but thats it. Nothing else is taped or tucked. Maybe the 94-95's are different from the 96-98's? I'll wait for your pic of yours.

I did not do the fuel pump rewire.

Can anyone confirm what relay I found under the fender apron near the fuse junction box?

4-G-rim
04-30-2008, 12:03 PM
Update:

John that 2 terminal black plug on the firewall is the fuel pump test plug. Not only I had to connect a jump wire to a 12volt source from the black/blue stripe wire. I had to also ground the black/yellow stripe wire too, once i did that the pump powered right up.

Now its pretty much narrowed down the the MPI relay. Is there anything else between the pump and the power source except the relays?

4-G-rim
05-01-2008, 11:52 AM
I am about frustrated trying to figure out why there is still no power getting to the plug for the fuel pump? I am thinking of bypassing the MPI relays right now. I went the the salvage yard and got 2 relays from 2 96-98 7g's and still there is no power getting to the pump? :mad:

I am missing something here or not looking in the right place?

4-G-rim
05-25-2008, 07:35 PM
Well last night I decided to check for power on the wires before I did Lawrence's relay bypass to see if I was getting power. I was getting power to the relay and power out of the relay (black/green stripe wire) and there was power going into that insulated plug behind the radio and there was power coming out of it. This made my curious because it was showing there was current going through the wire. So I checked where the fuel pump harness plugs into the chassis harness that runs from the drivers side all the way to the rear passeneger side where the pump harness plugs to the chassis harness. There are 2 plugs...and the smaller one was for the fuel pump assembly. Well I was getting power there from what my test light was showing where the pump harness plugs into the chassis harness. So I narrowed it down to the fuel pump harness and this was alot of progress I made...now that I narrowed it down to 2 feet of wiring, but was confused why there was still no power to the pump? I tested the positive terminal on the plug for the pump and I was getting power....so this left me totally confused. So I plugged it to the pump and turn the ignition to "ON" and the pump wasn't kicking on. This left me thinking more...because I was getting power to the plug, but its still not turning on the pump. I disconnected the plug and tested the positive terminal and I was getting power.

My test light was grounded to the chassis still...so I decided to get a jump wire and plug it into the negative terminal of the fuel pump plug and the other end of the wire I clamped the ground from the test light to that and did the test again and my test light didn't light up.

I came to the conclusion its a ground issue.....um duh! I removed the negative wire terminal from the plug going into the chassis harness and temporarily grounded seperately to the chassis and turn the ignition to the "ON" position and the PUMP KICKS ON!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!:smile::coo l:smile:

Now before I go celebrating.....its safe for me to run that ground seperately from the chassis harness right? I know somewhere in the clusterf*ck of wiring, there is a bad ground somewhere, but don't really want to find it unless its perfectly fine for me to ground that wire seperately.

Stewi
05-25-2008, 09:21 PM
yes its fine to ground it seperate, but the wire should be of the same gauge or larger than the power wire, and not be longer than 1 foot long. I personally would ground it to one of the set belt bolts under the rear seat, those usually have a pretty good ground. If not, just sand down to bare metal, ground it and hit it with some paint over it so it wont rust.

guynlidia2006
05-25-2008, 09:55 PM
damn.... i'll make sure i pm u if i ever have an electrical problem, ur the shit... You would of spent hundreds at a shop just for a ground...

4-G-rim
05-27-2008, 03:08 PM
Well here what I did to get the fuel pump running again. This may help those with a similar problem if they come across this thread if they search.

Here is where the chassis wire harness meets the fuel pump harness. The smaller plug on the right is the plug that is for the fuel pump. The black w/ blue stripe wire is the power wire and the spot to the right of it is where the negative wire is suppose to be at. I removed the negative wire from that terminal.
http://img384.imageshack.us/img384/1909/p5150404qp3.jpg

As you can see I cut off the electrical factory taping from the fuel pump harness to trace the wiring. The blue w/ blue stripe and black wire are the only 2 wires to run to the fuel pump. I simply grounded the black wire to the seat base floor pan.
http://img391.imageshack.us/img391/681/p5150406gh7.jpg
http://img370.imageshack.us/img370/7963/p5150405kv3.jpg

Once you do that..just turn the ignition to the "ON" position and you should hear your fuel pump kick on as it primers. Once everything checks out, just rewrap everything and start putting things back together. Here is my finished product:
http://img296.imageshack.us/img296/8067/p5150425vu5.jpg

Looks like factory, for the exception of the new ground point.

DOHCstunr
05-27-2008, 03:22 PM
kevin.....

I'm very suprised you haven't done the fuel pump rewire.

4-G-rim
05-27-2008, 03:45 PM
My setup isn't "big"...so I didn't see any reason to yet.

Though when the new motor is done...I will have to.

Distort
05-27-2008, 05:04 PM
Nice, glad to see you got it fixed.

DOHCstunr
05-27-2008, 05:35 PM
i just did it cause it cost about 12 bucks and i was bored, had the modding itch.

4-G-rim
05-27-2008, 05:48 PM
i just did it cause it cost about 12 bucks and i was bored, had the modding itch.

Haha :cool: I have everything do do the rewire and probably should. Maybe i'll have that itch like you did sometime soon.

kolio
05-27-2008, 06:53 PM
good job on the fix

DOHCstunr
05-27-2008, 06:57 PM
I want badly to see some Pro quality photo's of your car Kev.

You know any photographers? or perhaps an enthusiast on one of your local forums?
I want to see your car in all its glory.

It was never meant to be a garage queen. I want to see pics of it in its natural habitat! ;)

4-G-rim
05-27-2008, 07:38 PM
I have been wanting to take some nice "high quality" photos of the car...but I wanted to wait till after I get it painted. Though I do get a itch to just get some pics of it right now in its current form. There are several guys locally that take some really good pics and are deep into photography like Seth is.

I was thinking of getting in contact with one of them..but I am always busy with something else. The hood and roof are the eye sore's of the car right now, but I may be getting a new hood soon.

There is a track event in a few months and usually these "photographers" show up there for the local car scene event coverage. I am thinking of getting -G-rim suited up and ready for that event. I have posted a couple of pics of the car in the local forums..and so far every person so far has given the car real positive comments. Plus -G-rim has a very tiny reputation locally of being one of the "cool" cars seen on the street...mostly because its a Galant that looks the way it does and its turbo. :cool:

DOHCstunr
05-27-2008, 08:35 PM
You should go to an event with your local SCCA.
Get out and do an autocross Solo event.
Its such a blast! and its relatively cheap.

Take the 6g and g-rim.

You'll have a blast. I garuntee you'll get even more compliments. The guys love it when i bring out the GS.

Blue Ice
05-27-2008, 10:19 PM
I was telling Kev, we three should try to get together for a photo shoot / meet, i know a REALLY good photographer that would do it. He took all the better shots of my car.

http://www.myspace.com/rsellos
www.rabanmediax.net