Won't start after clutch change
 

I have a 2013 Frs. Several weeks ago I put a new ACT street clutch and LW flywheel in it. After putting it all back together It won't cranks but won't start. I've already checked a lot of things:
No ECU codes
has fuel pressure
no blown fuses
all connectors securely reconnected
no pinched wires
crank sensor replaced


It ran perfectly before, but now when I turn the key it just cranks, it will pop kind of like a backfire every few seconds. It seems like the timing got thrown off but I was hoping someone here could give me some more info before I pull the cover. While I have heard that turning the flywheel backwards (I did this while torquing the FW) could cause a timing belt to skip is that even possible with the chain on these engines?

"no ecu codes"
"crank sensor replaced"

If you've got an obd scan tool, did you check the engine rpm PID while cranking?

Hello RenegadeReaper and welcome to - The Forum - :clap:

We have some pretty smart folks on the forum that may be able to help you out - but, I ain't one of them - :sigh:

Someone will be along soon.


humfrz

@RZNT4R

"no ecu codes"
"crank sensor replaced"


To be more specific, I have and Open Flash Tablet which will give any cel codes. after checking my wires and making sure the fuel pump was working I replaced the crank sensor because with what info I could gather it seemed like the most likely culprit. It wasn't.


"If you've got an obd scan tool, did you check the engine rpm PID while cranking? "



Are you referring to the realtime data through obd2? Does the ecu use the crank sensor to calculate this? I didn't think of that before, but it's always matched the gauge roughly so i guess that would mean it's reading properly. or am I wrong?

@humfrz

Thank you and I hope you're right. None of the mechanics in my area are familiar with these cars.

Take it all back apart and flip the crankshaft position scale around. The teeth are supposed to face forward, away from the flywheel.


It's a common mistake.

Yes, the engine rpm PID in obd live data is a direct reading of the crankshaft position sensor.

It's easy to check as it requires no disassembly.

Well I have confirmed that the problem is not the sensor, but what are you referring to by the "scale?" The only thing I remember with "teeth" was the flywheel itself, and the plate behind it was definitely facing away.

Yeah. The crown shape on that plate should be facing in, toward the crankshaft sensor. Phew!

People do install it backward.

Try RZNT4R's idea of reading the RPM.

TBH I'm not sure what reading the rpm is supposed to tell me other than that the crank sensor is working. I originally thought that I might have damaged the sensor while replacing the flywheel but since I already replaced it, that apparently wasn't the case. I was hoping to get some other ideas as to what might be wrong. the short version is: still have fuel, air, spark, and no cel codes but it won't start and the timing doesn't sound right.

Ah, but replacement doesn't confirm operation. Might be the connector. Might be a bum part.

Well, that just leaves compression and timing - :iono:

OK, folks, how does one check the timing on these new fangled machines??

I was good with a couple of lengths of wire and a 12V light bulb and later on a timing light - but, today, I have no idea.

The OP needs help!

Anyone?


humfrz

By looking at the live data you're looking for a low or intermittent reading. The crank sensor is (surprisingly) a pretty old school AC voltage generator, if it or it's reluctor are misaligned, sufficiently high AC voltage can't be generated.

After going over what I did with a rather knowledgeable mechanic in my town I think I figured it out. If the crown plate that Ultramaroon mentioned is what the crank sensor is reading then I probably didn't put it back properly, there should be marks that I have to line up right? So atm even though the rpm is right the sensor is picking up the wrong crank position.

Check out my build. I have pics of my clutch install and the correct plate orientation.