Timing jumping from 20* to 12* or less Does this mean I have a bad Crank sensor??

[Hashiriya415]

I was just using the BLAZT consult and my timing light and I saw that the timing was jumping around. My ECU was staying around 15* and dropping down below 8*, and this tuned ECU I just swaped out was at 20* and jumping to around 12*.
I have tried to change the timing all the way from retarded to advanced and the backfiring/misfiring is still there, I also took the cap off the Crank Angle Sensor but didn't find anything wrong

Does this mean its a bad Crank Angle Sensor?

My S13 Blktop SR20DET has started misfiring and lot've backfiring all of a sudden.
When the car is cold it doesn't backfire as much but when its warmed up its really bad, there is a lot've unburned gas seen out from the back of the exhaust and I think the Crank Angle Sensor might be the problem.

checked my fuel pressure
checked all the spark plugs
checked all the ignition coils
checked my compression and all 4cylinders were even.
what else could it be causing this?

[-=RS13=-]

Make sure your TPS is unplugged while setting/checking timing. The Ecu will pull/ advance timing at idle.

[slider2828]

Also, did you take apart the head and block or messed around with the timing chain? If so, you might have skipped a tooth.

[zaneithan]

check your bov connection to its vacuum source, i had mine on the wrong nipple and my timing was jumping around when i tried setting it

[Hashiriya415]

what i mean, its wrong for the timing to be jumping around, it should be a steady degree like 15* + or- 1. But mine is jumping around from 15 to 8.
I have not messed with the timing chain at all, I was just driving and all of a sudden it started running bad, and i don't have a BOV

[blownmotor]

tried using a stock ecu to see if anything changes

[slider2828]

Check broken vacuum hoses or just replace them all. Also check for exhaust, intake leaks, and cracked hose couplers any where used. These sound like boost hose couple issues.... Trust me

[landins13]

if you are still on an ecu and the 02 sensor has gone bad or the MAF has gone bad the ecu will automatically advance timing and dump fuel to prevent detonation.

http://www.240edge.com/manuals/s14_sr20det.pdf

^^^^this is a link to the FSM if you dont have it, you should be able to find a troubleshooting process in it to fix the problem.

[Hashiriya415]

I have tested the whole system for leaks and no problems.
O2 sensor is good its reading showing proper voltage.
MAF is also showing proper voltage.
and I have been using my stock ECU

[slider2828]

Well you elimnated lot of stuff. So you might as well trade someone for a CAS and try it.

[Hashiriya415]

thanx slider, any body else got any more advice

[projectRDM]

Cam angle sensor. There is no crank angle sensor on an SR

[Hashiriya415]

yes thats true its called the cam angle sensor.
Any reason why the ECU would not set a code?

[slider2828]

Simple there isn't a fault code for it. There is a set number of codes and there just ins't a code for it.....Intermittent problems don't always come up on the ecu.