Okay

 

It is original all the icms I've seen have always had Singapore in them,I haven't had any issues with them

 

I just got the software working, went into code all that was there 11 SES.
i notice without cranking it says RPM 45, and the TPS changes when i push gas pedal.
I reset the codes and tried to start, there kind...of seems like some kind of spark??? not sure but now to NO CODES.
shouldn't i get some codes with things disconnected?

Thanks!

opti

intake

 

Yeah it had the origanal coil on it so i replaced it with a AC Delco and i cleaned up the ICM and used Arctic Silver on it.
But i just wonder if this could be my problem from the start(ICM).

 

Key on, not started, it’s normal for RPM to show 45. What you need to look at is what happens when you start cranking it? The RPM should increase to show the actual cranking speed. And the tach needle should move upwards a couple hundred RPM. Lack of RPM (other than 45) indicates no pulse signal from the Opti.

Loss of low res pulse signal from the Opti sets DTC 16. But the code doesn’t set while cranking until the PCM receives a certain number of high res pulses without seeing a low res pulse. First, you have to let is crank for an extended period of time before releasing the key. But even then, if there are no high or low res pulses, the DTC can't set because there are no high res pulses to count.

Many of the diagnostics that set the codes can’t be run until certain operating conditions are met, and some codes won't set if other codes are present. It’s complicated. But it’s all described in the factory service manual.

 

I just tried cranking it for about a minute, the tachometer went up about 2 notches and the computer said about 170 RPM

Thanks!

 

Check for spark on the coil wire, and at the individual plugs.

 

Question:
since i have RPM does that mean as far as the opti is concerned the engine should fire up?

Thanks

 

Optical module should be OK, but Shoebox's test is also positive:

4th Gen LT1 F-body Tech Articles

That would prove everything up to the ICM. But checking for spark will also tell you. If you have spark at the coil wire, everything is good up to the Opti. If you have spark at the plugs, the cap/rotor section of the Opti is good.

 

i will check spark tonight.
you know what is really crazy? when the car died i suspected it was the opti, i took it apart without disconnecting the computer from the battery. when i took the opti apart it looked really good inside with some oil leak but not any got on the optical or wheel. i then put new seals, cap and rotor. installed it to see if it would start, no start. so I it got the parts for the scan9495, plugged it in and the only error was DTC 11-ses. That is what so crazy about this. i did replace the factory coil with AC Delco but kept the same Factory ICM.

THANKS for all your help!

 

If you disconnected the battery, all stored codes were lost. The code for the Opti can't set again if there is no high resolution signal.

If you pull the Opti off:

- with the key on, harness connector on the Opti, ground the metal Opti casing to the engine. Measure voltage between the red/black wire and the pink/black wire. Turn the driven part on the back of the Opti slowly, and watch the voltage. It should switch back and forth between 0 and 5 volts 4 times for every 1 rotation of the driven part.

- Then measure volts between the purple/white wire (or light blue/black - whichever yours has) and the pink black wire. As you rotate the back of the Opti slowly, the volts will jump up and down rapidly between 0 and 5 volts. 360 times for each full revolution (don't bother to count..... just look for rapid switching).

If you don't get the voltage switching, key on, pull the connector off the Opti and measure volts between the red wire and an engine ground. Should get ~12 volts.

 

I have spark from coil and plug #1 didn't test the other plugs.
my thinking is the opti must of moved on me when i installed it. but it slipped on real easy and is flush so i don't know how it could be off. its not giving any indication of timing being off.

 

Depends how far off it is. One guy thought he got the dowel pin in the correct hole, but the pin was too short and somehow ended up in the cloverleaf hole right next to the index hole. Car started and ran good enough that he did not expect it was not indexed correctly. We discovered this because his car was a 96 and he was getting a code for the crank position sensor reading being “out of range” = the crank position signal differed too much from the cam position signal from the Opti.

I kept telling him the pin was not in the index hole, he insisted it must be right, because he didn’t have to force it to mount flush. When he finally relented and pulled the Opti, pin was not in the index hole.

Two points - 1) it can go together incorrectly, even if it isn’t forced; 2) the engine can still start and seem to run decent if it's just a little bit off. A large offset can prevent starting, but if you have spark and fuel, you will get popping and backfiring through the open intake valves.

 

no popping or backfiring. when i tried to put it on it keep moving on me because it wasn't sliding on easy, and i just don't want to pull the cap and do it because i sealed it up real good to not leak.

So what would you do at this point?

Thanks again for all your help i'm learning a lot from this.

 

Injuneer

I pulled the opti off and it was on in the right place, see pic

then i grounded the opti while off but all wire still contected. I turn the key and spun the opti it back fired throught the intake.
then i reinstalled the opti and it ran for 1-2 seconds and died. i tried to start it again and all it would do is crank.
i connected the scanner on and not it has a code 15 water temp.

So what do you think???