Let's start over. I can’t remember all the info in the 30 posts.

Was it starting and running with the old Opti?

What exactly did you replace? It’s still not clear to me. I know you got the AIP cap/rotor. Did you also replace the base of the Opti, if so what brand? If not, did you remove the old base and then reinstall it before you tried to run it without the water pump?

In one Opti problem that GaryDoug tracked down and repaired, the optical module was working until it got warm. He opened it up and found the heat was causing a contact to be lost on the printed circuit board. He was able to repair it. I understand you only ran it long enough to verify spark, but maybe that's enough to cause a problem..... I really don’t know.

DTC 15 is for the coolant temp sensor in the water pump - open circuit. Did you reconnect it? Is the wire damaged? That shouldn’t prevent it from starting. I know you don’t have the water pump installed, but the sensor needs to be connected to avoid the code. If the harness is connected and the wire isn’t damaged, you will need to check the sensor and the harness, using Shoebox's instructions - link below:

What am I supposed to see in the photo that proves the Opti was indexed correctly? I don’t even see the dowel pin. Is it the correct length?

http://shbox.com/ci/ci289.jpg

4th Gen LT1 F-body Tech Articles

 

it started like this: i jumped on it to get ahead of traffic and when the rpm's got up it started cutting out loosing power so i backed off. I went into a store came out drove to another store 5 miles away after hour there, when i left it was hard starting, tried to leave and didn't think i was going to get out of the parking lot. so i went home about another 5 mile basic limping there. the next day i went out to the post office 6 blocks away and it almost didn't make there and back. a few days after that i tried to start it and just cranked & cranked no fire. so 2 weeks went by and it was a hot day i tried to start it and it started but would pop if i gunned it.

This opti is a NEW GM i had installed about 20K ago when the water pump started leaking. So i took it apart the cap & rotor didn't look too bad (see pic) and put aip cap & rotor





The pic was showing that i took the opti off to see if the pin was index in the right slot.

thanks for any help you can give.

 

You have to use a systematic approach to tracking down the problem.

Every time you try to start the engine, you need to be watching the tach to see if the needle moves upward when the starter is cranking the engine. That is a very good indication whether or not the Opti is working. Once you establish it's not an Opti problem, you can focus on the ICM. While the engine is cranking but not starting, check for spark at the plugs.... 1 or 2 is enough.

If no spark, have the ICM tested. Make sure they test it multiple times so it gets hot. If the Opti is OK, and the ICM is OK, then you focus on fuel. Starting and running for a couple seconds can indicate a problem with the fuel enable signal from the theft deterrent module (TDM). Then there’s the outside chance the fuel pump is failing.

What I can’t understand is the lack of codes. There is a code for the fuel enable signal, and that will set during cranking. There is a code for the ICM, and that only sets while cranking. There are codes for the Opti, but they may not set during cranking, depending on which of the two cam position signals are lost.

 

Sounds like when I had a coil going bad. There were no codes.

 

In post #19 he indicates he replaced the coil with an AC Delco.

 

yesterday post #30 when i pulled the opti off to make sure it was index right, i thought i would test it like other were doing on the car and spinning it.

when i did that i heard a clicking noise by the area of the anti lock brake unit then the engine back fired so i knew i had spark and fuel.

So i installed the opti and cranked the engine over and it ran for 1-2 second and died like turning the key off.

I then got the 9495scan going and saw code #15 so cranked the engine for a minute and it just cranked no trying to start and i had rpm around 170.

The fuel pump as i know is factory. One other thing came to mind of what i did on the day i jumped on it, i stopped @ costco and got gas.

thats it guys!

HELP!!!!!!

 

Yeah, but who can keep up. Hope the new coil is good.

 

I know.....I read through so many of these threads every day that I can’t remember all the details in the longer ones, and sometimes confuse two threads. That’s why I wanted to regroup, and summarize what happened in post #30, above. That's also why using asignature is important, because then I don’t have to scroll all the way back to the first post to figure out what year and what level of modifications we are dealing with.

And being older than dirt isn’t helping my memory.....

 

OK, so every time i crank it i get RPM about 170, i get spark @ plug #1. and when it does fire for a second i get code #15 bcause no water pump on the engine.

So 2-3 days ago i pulled the fuses for the PCM. Today i put the fuses back in hookup 9495scan turn key on NO codes. i then crank it over it started for 1 second, i cranked it again fired 1/2 second. then i cranked again it just cranked no fire all this time i get RPM. i checked the codes and got #15.

Any thoughts???

Thanks!

 

Is the coolant temp sensor in the water pump hooked up? If it isn’t it sets that code, It’s a 2-wire sensor, so it doesn’t need the water pump to be attached to the engine. If the harness is attached to the sensor, you have a faulty sensor, a damaged harness connector or a damaged wire.

DTC 15 does not prevent the engine from starting.

I explained this in post #31. Have to read things thoroughly.

Shoebox has a test procedure:

4th Gen LT1 F-body Tech Articles

If you have tach movement and spark, the next step is to go back and read what I already posted in post #33. Again, you have to read the complete responses and follow up.

 

i know why the code #15 because no temp sensor is hooked up, i was just stating that only when it did run for a second, then i would get the code.
1) opti is working (RPM)
2) ICM is working (Spark)

So what if i'm getting gas???
Is there any condition that the pcm would NOT energize the Injectors?

Thanks!

 

it looks like the fuel pump bit the dust!

Thanks everyone that helped!!!

 

Please post the results as well too. In future if someone has exact issue they will learn from this thread 😁😀😎

 

To Be Continued ...

(When i have the car up and running, and do some tests, like WOT, I will right my conclusions to this ordeal)

 

I got the fuel pump in using the cutting hole to get to it, and it running.



Can you check this scan file and see if anything jumps out at you?

http://vcs-llc.net/9495scan/DLOG-Save-2019Sep13.csv

Fred, thanks for all your help. i have learned a lot from you!!!