Not another crank no start!

[dim22]

Hi everyone, after 3 and a half months of building my baby it was d-day.
Unfortunately my fuel pump is not getting 12v neither is the fuse #18.
I dint check the relay because I dint know which one it is but with bantley manual I make sure it works.

I am here to ask what is the most common thing. What I was thinking is the anti theft is messing with me. I did have the CPU and board computer disconnected at one point same with battery. It would be amazing to see it run after working on it for this long.
The car is OBD1 1995 M3 Coupe. Thanks

[Pring]

HAHA YES!! I had this same issue .. jump the relay with a peice of wire... then start the car.. when the car starts running.. Pull the wire out. That did the trick for me.. you gotta be tricky !

P.S - I have the same car so I'm hoping I just gave my first bit of useful information !

[dim22]

Thanks I will def try it.

[Pring]

Let me know if it works out .. Just connect to something that you know has power and send it to the relay manually.. Or to the fuel pump fuse.. I dont remember which I did when it was me in your shoes but I def have been there .

[dim22]

Anyone else has suggestions?

[Pring]

I take it that didnt work ? did you take a meter and find something with constant power and then sent power directly to the fuel pump fuse ? It should at least start the car regardless of anything else.

[dim22]

LoL I dint try it yet the car is not here. I will do it first thing tomorrow. Because my shop is away from any internet connections I was trying to get more ideas to test tomorrow.

[crazyyardie]

did u installl achip in your computer box while doing the build. if so check that the chip went in the right way it has a notch u must line up . it will just crank and not start if its in the wrong way.

[dim22]

The car had a chip when I got it, I will check to see if its the right way.

[crazyyardie]

oo sorry for a sec i thought u were boosted and changed the chip . you prob sound slike a bad crank sensor. have u had it scanned ?

[dim22]

That did not work. Basically this is what i got from testing.
When I crank the engine over or turn the ignition on I dont get any voltage at the pin 30 or 85. The Relay for the fuel is same way i get 12V at 30 and nothing at 87 and 86.

When i crank, at fuse 18 i get 7V, but the plug for the fuel pump does not get any. Is that a ground issue?

[dim22]

My car is boosted I just finished it. I need it to run before i can get it to the tuner. It has a Tuner Motorsports chip.

[crazyyardie]

7 v is an issue try checking the resistance of the wires maybe u have a ground issue. U said u didnt remove the chip it has been in the dme from u got the car right

[dim22]

Yes I did not remove it If I do will the ECU go to a default setting?

[crazyyardie]

not it wont go to default. I still think u need to check on that crank sensor

[dim22]

Yeah first thing tomorrow.

[Pring]

Try sending power straight to the fuse.. Have a buddy hold it there while you start the car.

[dim22]

I had to take the intake manifold off because I had the crank sensor connected to the cam sensor :-( duh. I am very confused because I took my time separating the connectors for each sensor. Now I have 2 extra sensors and zero available connectors to hook up to.

[Boots]

did you try clippping the green #7 ews wire. that did the trick for me

[Jrdeamicis]

Fuel Pump turning on completely is triggered by the ECU and the Crank Sensor. Meter your crank sensor and look for mV while cranking. If you have a scope use an oscilloscope to view your crank signal and make sure its solid.

[dim22]

Yes Finally its running, i drove it. Besides the something around the turbo leaking oil it runs good but... ugh it wont idle. Thanks for all the help now i have to find out why it wont stay at 750rpm.

[Jrdeamicis]

Yes Finally its running, i drove it. Besides the something around the turbo leaking oil it runs good but... ugh it wont idle. Thanks for all the help now i have to find out why it wont stay at 750rpm.

Sorry, didn't see your reply two above mine.

Do you have a VAC gauge? What is it at idle? Vac leak?

[dim22]

vac says 8-15 at idle.
yeah must be leaking. But it has a check engine and i have no clue how to check it.

[dim22]

Also the car has a stupid Tuner Motorsports chip which makes my I/F ratio go to 8:1 if not lower when i get into it and it seriously stalls out. I have to call ics and see if they I can buy a default chip.

[Jrdeamicis]

8-15 is a pretty serious leak if you are reading off the manifold and its a somewhat stock motor.

Well if you the AFR are way off that code could be for a bunch of things.

Search gas pedal trick for OBD1

Bad mixture is going to blow some shit up, be careful.