Motor is back in but wont start

[cat97628]

So after a couple weeks of pulling the motor and replacing all the seals and gaskets I now have it back in but it wont start. I have replaced the following.


This is for my 91' 325i that is stock



Plugs
Wires
Cap
Rotor
Timing Belt
Tensioner
Water Pump
Hoses
Radiator
Exhaust
O2 Sensor
Fuel Filter
Rebuilt Flow Matched Fuel Injectors
Torque Convertor
Trans Pan gasket and filter
Oil Pan gasket
Oil Filter housing Gaskets
Valve cover gasket
Rear Main Seal
Cam Seal
Exhaust Manifold Gasket
Intake Manifold Gasket
Thermostat
Thermostat Housing

Cold Start Sensor
Coolant Temp Sensor
Oil Pressure Sensor






So as you can see I have had my hand on pretty much every part of this motor and trans and I believe everything is back in the car, I have no extra part nor do I have any unknown electric connections that are not plugged in.


I have tested and I have fuel at the rail and spark to at least one plug.


The car just cranks and cranks. When I pulled the plug it does not seem wet so am I thinking that something may be off with my injector but I could be wrong. I am covered in gas from changing the fuel filter and testing the fuel hose so I could do a stiff test on the plug.



What Am I missing. Where should I start.

[zaq123]

check that both timing marks line up on Crank and cam. check all spark plug wires, check fuel pump. If there is fuel and fire, it should start

[cat97628]

just tested listening to the injectors and I hear nothing coming from them. According to everything I have read today I should hear tapping when they pulse. I believe I am not getting power to the rail. Off to do my next troubleshooting.


I have confirmed spark and I had confirmed timing a dozen times before I put the motor back together and into the car. I have fuel to the rail but unsure as to the pressure. This was a running car before I decided to "Fix" it.

[tim88325is]

Make sure the C191 plug connection under the intake is 100% good, check behind boots for corrosion...

[cat97628]

Tried to peel the boots back last night but they won’t budge. I seen no corrosion on the pins. I was messing with the female side of the plug last night and I was seeing weird voltage on pins 5 6 and 7. Had 12 volt on one pin and 5 volts on the other two. Key was on but wasn’t cranking. Going to pickup some diag tools tonight from HF, noid lights, fuel pressure gauge, a test lamp, and a stethoscope.

[cat97628]

ok for those keeping score I have spark, I have fuel to the rail but no idea about fuel pressure, and I now have confirmed the injector harness is working correctly. I have bought a noid light from Harbor freight and each injector lead fires. I am now testing the reman injector I installed to ensure they are actually working. After that I think I am running out of places to check other than compression and timing yet again.

[cat97628]

so I tested both the old and new injector on the bench with a 9v battery and the new injectors make no noise at all, the old injectors click every time i hit them with the battery. I installed the old injectors but still nothing fired. I am really at a loss here.

[cat97628]

just pulled the crank position sensor and it has a huge chunk out of it and it looks like its been like that for some time. I test with the multi meter and I get no readings. Why would I have spark if this was so chewed up?

[e30davie]

I you have injectors ticking and spark, then the crank position sensor works.

[cat97628]

Yeah did an ohm test and came it at 530. Still ordered a new 1. Stuck for now waiting for replacement injectors and the stupid clips. I lost two of them taking the rail off and now the injectors won’t stay in the in take manifold. Will test compression tomorrow and may do a leak down test. Really running out of ideas

[tim88325is]

I wouldn't buy any more parts but start testing methodically all the wiring and connections, probably something over looked. Although I had the same problem a while back and my ECU was bad, it was getting very hot to the touch.

Don't give up, this kind of stuff tough trouble shooting can painful but rewarding. You will feel like a real mechanic solving a complex problem opposed to just a tinkerer....

I still would try to get behind those C191 boots, mine were corroded on the back side where water can run into. A few connectors were holding on by a thread and caused weird problems.

[iwantspeed]

check if the fuel hoses are installed in the correct orientation


check if the crank position sensor is male plug if plugged in to the corresponding female plug on the engine loom


you can accidentally plug in the spark plug impulse sensor wire.


read this carefully

https://www.r3vlimited.com/board/showpost.php?p=4472729&postcount=16&p=4472729&postcount=16

and this

https://www.r3vlimited.com/board/showthread.php?t=364705

[redlightpete]

An old fashioned troubleshooting technique is to try starting it with starter fluid. If it runs with starter fluid, you know the ignition works and vice versa. If it doesn’t run with the starter fluid, and you have a strong spark, you know there’s a timing problem (or inadequate compression).

[cat97628]

I wouldn't buy any more parts but start testing methodically all the wiring and connections, probably something over looked. Although I had the same problem a while back and my ECU was bad, it was getting very hot to the touch.

Don't give up, this kind of stuff tough trouble shooting can painful but rewarding. You will feel like a real mechanic solving a complex problem opposed to just a tinkerer....

I still would try to get behind those C191 boots, mine were corroded on the back side where water can run into. A few connectors were holding on by a thread and caused weird problems.

I will try the boots again when I put the new injectors in this weekend and I am done with parts for now. The CPS was shot it had an inch long gash in the wire and I am really surprised it was doing anything at all.

[cat97628]

check if the fuel hoses are installed in the correct orientation


check if the crank position sensor is male plug if plugged in to the corresponding female plug on the engine loom


you can accidentally plug in the spark plug impulse sensor wire.


read this carefully

https://www.r3vlimited.com/board/showpost.php?p=4472729&postcount=16&p=4472729&postcount=16

and this
https://www.r3vlimited.com/board/sho...d.php?t=364705

Thanks for the info. Any idea on the hoses? I tested what I thought was the feed hose by putting it in a bottle and hit the key. About 1/2 a cub of gas squirted out. That hose is hooked directly to the rail. The other return hose is hooked to the FPR.


When I took the wire harness loose I had taken the plugs off first and left the CPS connected. I did not take the harness loose from the car I just draped it back onto the windshied. The CPS was disconnected until last night.