Interesting ignition problem, delayed start, Spark?

[Rob 1]

Hi All

I just wanted to say that I may have done something dumb by editing one of my replies instead of making a new reply keeping the post active. I am new but a quick learner.

Rob 1

[Ozark Lee]

Your edited post makes much more sense. I read the earlier one and didn't quite know what to make of it.

Since you have tried multiple camshaft position sensors I think my next step would be to clean up the edge connector and the socket on the ECM with contact cleaner. If that doesn't fix it then the ECM itself is the next step. You should see a distinct pulsation on terminal 4 so either the ECM is not seeing the signal from the camshaft position sensor or it is not able to send the control signal on the the power stage for the coil.

On all of the documentation I have the ECM is a black box with no component level detail so I can take you no further beyond "replace with known good".

Stay away from the stealerships if you need a new ECU (ECM). They are all over eBay.

...Lee

[Rob 1]

Hi Lee

Thank you for getting back to me, tomorrow I will try your suggestion about cleaning the contacts, which I have done once before and I will make sure that both ends of wires for the power stage have good continuity. What about the signal from the CMP does it make a difference if that signal does not go 0-5V
is the 0.7-5V acceptable. Is there a possibility that maybe the something else is causing the pulse signal not to trigger the coil.
I am not that well versed on electronic ignition, give me a set of points they are less expensive and easier to change and you can see if they work in the dark. Now I am giving away my age.

Thanks again

Bob

[Ozark Lee]

What about the signal from the CMP does it make a difference if that signal does not go 0-5V
is the 0.7-5V acceptable. Is there a possibility that maybe the something else is causing the pulse signal not to trigger the coil.

It may actually be going to zero but the meter doesn't react quickly enough to settle there between pulses. Even the worst old slow TTL circuits have a 0.8 volt low trigger threshold, CMOS components are more like 1.3 Volts for a positive low trigger so it should be OK. I'm going to guess that you don't have an oscilloscope laying around but that is the real way to accurately see the pulse train.

...Lee

[Rob 1]

Hi Lee

No scope. Boy I thought I was early online, did you get any sleep? Well I off to the car let you know how I did.

Thank you

Bob

[klm]

PROBLEM RESOLVED !!!!!

Lately (other than the delayed start) the the engine has had trouble turning over, intermittent . I was not sure if it was the starter or Battery. Battery checked out and appeared to be charging well so I went to the junk yard and picked up a used starter. With the new starter it starts right up every time. I can only guess that all this time the starter was turning the engine over to slowly to get the correct signal from one of the sensors, crank or cam position. I have been fighting this problem for a year or more now.

As the starter got worse the car would throw a CEL for Cam position sensor for the last few days, as it turned over slowly and erratically. I never thought the starter would solve the delayed start problem so while at the junk yard I was able to take what I wanted off the junk car so I grabbed the crank and cam pos sensor, alternator and coil, figuring that I would change them one at a time to try to resolve the delayed start issue. Thanks for the advice and assistance.

Kurt