OBD2 > OBD1 GSR EG

[Thateguhate]

ok, heres the deal. I hate starting a thread but I cant seem to find the problem.


I have a 97 USDM GSR motor in my eg, freshly put in.. The guy doing my swap cannot get the motor to even crank. He can turn the camshaft himself by hand but not smoothly due to a bit of rust. Its an OBD2 motor although were using an OBD1 94-95 GSR P72 ECU w/ a OBD1 Wiring harness.

Not the OBD2 wiring harness / w the jumper. (is this our mistake)

The power seems to be going to the starter, and it will click but no crank to the motor at all. The grounds have been checked but I have been arguing with him being ive been told that there is more than one ground that has to be in and operating for the motor to start. Can anyone tell me how many grounds should be there to have the motor operational?!?! I did an auto> manual so I dont know if we have overlooked any other possibilities. Thanks in advance.

 

[dok]

the p72 is manuel right??? oh and is the obd1 wire harness from the plug or all the way to the ecu ??? because if you just unplug it and used the the stock harness from the tower to the ecu that may be the problem i would go to the junk yard and get the whole harness from the ecu to the motor obd1 it has to be a manuel harness...

 

[98bswap]

Quoted post[/post]]
ok, heres the deal. I hate starting a thread but I cant seem to find the problem.


I have a 97 USDM GSR motor in my eg, freshly put in.. The guy doing my swap cannot get the motor to even crank. He can turn the camshaft himself by hand but not smoothly due to a bit of rust. Its an OBD2 motor although were using an OBD1 94-95 GSR P72 ECU w/ a OBD1 Wiring harness.

Not the OBD2 wiring harness / w the jumper. (is this our mistake)

The power seems to be going to the starter, and it will click but no crank to the motor at all. The grounds have been checked but I have been arguing with him being ive been told that there is more than one ground that has to be in and operating for the motor to start. Can anyone tell me how many grounds should be there to have the motor operational?!?! I did an auto> manual so I dont know if we have overlooked any other possibilities. Thanks in advance.

As long as you used the stock eg harness and modified it for v-tec unless it is a v-tec harness you should have no problems. Is the starter good. Also does the crank turn, the cam is not what is important to turn unless the timing belt is on.

 

[Thateguhate]

ok so the wiring is good, and the crank is a check as well. Which narrows down to grounds, and the good ol battery.

After I thought about it, the car sat for close to 5 weeks now. Im thinking the battery doesnt have the charge it needs to crank the motor, and my installer doesnt know this. I'm gonna try and call him up to tell him to charge my shit, or jump it and see whats up.

The thing is, to the average mechanic that would be the first thing to look at..

Quoted post[/post]]
the p72 is manuel right??? oh and is the obd1 wire harness from the plug or all the way to the ecu ??? because if you just unplug it and used the the stock harness from the tower to the ecu that may be the problem i would go to the junk yard and get the whole harness from the ecu to the motor obd1 it has to be a manuel harness...

and the obd1 harness is from the plug. We could try that, he actually has one I think. But despite all of the OBD1 >OBD2 It wouldnt effect the startup, but more or less the overall driveability right??

 

[VTECin5th]

Quoted post[/post]]
ok so the wiring is good, and the crank is a check as well. Which narrows down to grounds, and the good ol battery.

After I thought about it, the car sat for close to 5 weeks now. Im thinking the battery doesnt have the charge it needs to crank the motor, and my installer doesnt know this. I'm gonna try and call him up to tell him to charge my shit, or jump it and see whats up.

The thing is, to the average mechanic that would be the first thing to look at..

Quoted post[/post]]
the p72 is manuel right??? oh and is the obd1 wire harness from the plug or all the way to the ecu ??? because if you just unplug it and used the the stock harness from the tower to the ecu that may be the problem i would go to the junk yard and get the whole harness from the ecu to the motor obd1 it has to be a manuel harness...

and the obd1 harness is from the plug. We could try that, he actually has one I think. But despite all of the OBD1 >OBD2 It wouldnt effect the startup, but more or less the overall driveability right??

Your harness is not the problem.
You either forgot the Transmission ground or the thermostat ground or both.
The tranny ground not hooked up= the car won't crank.

 

[Thateguhate]

Quoted post[/post]]

Quoted post[/post]]
ok so the wiring is good, and the crank is a check as well. Which narrows down to grounds, and the good ol battery.

After I thought about it, the car sat for close to 5 weeks now. Im thinking the battery doesnt have the charge it needs to crank the motor, and my installer doesnt know this. I'm gonna try and call him up to tell him to charge my shit, or jump it and see whats up.

The thing is, to the average mechanic that would be the first thing to look at..

Quoted post[/post]]
the p72 is manuel right??? oh and is the obd1 wire harness from the plug or all the way to the ecu ??? because if you just unplug it and used the the stock harness from the tower to the ecu that may be the problem i would go to the junk yard and get the whole harness from the ecu to the motor obd1 it has to be a manuel harness...

and the obd1 harness is from the plug. We could try that, he actually has one I think. But despite all of the OBD1 >OBD2 It wouldnt effect the startup, but more or less the overall driveability right??

Your harness is not the problem.
You either forgot the Transmission ground or the thermostat ground or both.
The tranny ground not hooked up= the car won't crank.

werd.. thanks..I'll pass this onto him. Thats what I thought, but when i brought up the tranny they laughed at me like I didnt know wtf i was talking about.

 

[VTECin5th]

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werd.. thanks..I'll pass this onto him. Thats what I thought, but when i brought up the tranny they laughed at me like I didnt know wtf i was talking about.

You would've been better off doing the entire thing yourself...even free labor is bad if they don't know anything.

(PS: The crankshaft doesn't spin smoothly by hand, take the spark plugs and it will turn smoothly by hand. I doubt it's a rust issue)

 

[Thateguhate]

I heard that, dude isnt listening.. Swears up and down its rust. I dont even think he's checking the things I've been pointing out.

 

[VTECin5th]

Quoted post[/post]]
I heard that, dude isnt listening.. Swears up and down its rust. I dont even think he's checking the things I've been pointing out.

Sounds like your mechanic sucks.
Instead of telling him what to check, you do it!

 

[Thateguhate]

Quoted post[/post]]

Quoted post[/post]]
I heard that, dude isnt listening.. Swears up and down its rust. I dont even think he's checking the things I've been pointing out.

Sounds like your mechanic sucks.
Instead of telling him what to check, you do it!

perzactly which is why Im having it towed to my house today to check this shit out.