carmanroads

I recently boughta car that looks good but woundnt start, no spark, I bought a cranksaft sensor and put in in , no change, I got a obdII (snap on) code reader and see the crank and cam sensors are there while cranking and in sync. I have looked at all the fuses and connections and put a cap ad rotor on it just to make sure, no change, I evn went as far to make sure my code reader was working to make it trip codes by pulling the distributor wire plug off, then got a camshaft code , which went away as soon as I pluged it back in, as much as I hate to just change part, I fear I need a cpu, what els could it be , by the way ,is there a fuel pump reset( after hit) if so where is it?

78D200

Have you checked power coming into the coil and going out?

carmanroads

only with the funtionality tes tmode on the code reader, with no results untill I unpluged the dist. and or the ASD relay. I assume the coil is under the dist. cap since there is no coil wire to the cap, I should run the test again with a test light going into the coil, as far as power out of the coil,.... I have no power to the spark plug, help me norrow down to power out of the coil please thanks

PK1

You need to follow the spark "train" from cpu out to crank sensor to cam sensor to dist to coil etc..... Look at your manual for the "trains" route and go from there.

Work from the cpu out or everything will appear to be bad.. You can do this with the "key on" and a test light or volt meter.

Do not replace the cpu. They do NOT go bad as often as most folks think IMO. Do not discount factory alarms and aftermarket kill switches. Those buggers can be the cause too.

As stated above, measure coil primary and secondary resistance to make sure you are within spec and don't have a weak spark issue.

Your cam sensor code when you pulled parts indicates that OBD2 is working and since you have no other codes that is why I mentioned alarm system.

Good Luck!

78D200

I asked about the coil becuase you mentioned that you replaced the cap and rotor. All you need to do is trace the plug wire in the middle of the cap back to the coil.

Depending on the motor, you may have a coil pack per plug. I'll look to see if I still have my book on these cars and see what it says.

carmanroads

Ok , no coil wire on the outside of cap, the inside of the rotor is metalic, suggesting the dist derive shaft is charged by the coil, any way thats how it looks to me

carmanroads

So today I started testing th wire I believe is into the coil, no juice on the test light with the key on , untill I hit functionality test on the coil wth the obdII I tried to turn it over while the test was running but lost power, had to start the test over to get light again, Inot sue what this means, My first thought was a short in the coil,.. cpu shutting power to it, I not sure where to go from here, any help would be be appreiciated.

carmanroads

Well I replaced the distributor with a reman. from the part store and it started right up , however now I have 2 codes while it runs, no cam position sensor, no crank position sensor, I think its an issue withth reman part.

78D200

That's weird as the dizzy gets signal from the ECM about when to fire which the ECM is told that from the cam/crank position sensors.

I tore apart my garage and couldn't find my book either. I think a friend "borrowed" it.