'81, inconsistent spark firing
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From: Deep in the Pisgah National Forest
Secondly, did you get a chance to put a compression tester on the cylinders to see what it looks like? So we can rule out that? It's unlikely, but always possible a rocker slipped off, or there's a bent push rod (or flat cam lobe). I had a CCC pickup once with a flat cam lobe back in the day which was tricky to figure out.
Do you see fuel squirt out nice and strong from the accelerator pump?
What was the reason you replaced the distributor? Did this issue occur before you replaced it?
Hang in there ....we'll help you zero in on things. I've driven several CCC carb'd cars to well over 200k miles and they all ran great with few problems (better than old-school carb'd cars). Who knows, the problem may ultimately not have anything to do with the computer or sensors. People tend to out of the chute blame the computer and sensors on these older cars. Sometimes it is, lot of times it isn't. I see that on the Jeep forums all the time.
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The secondary air valve is spring loaded. There is a very small allen set screw underneath the left arrow.Back it off and the valve flops around. You turn the screw shown with right arrow till the door just closes, add 3/4 turn, then tighten the set screw.
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From: Deep in the Pisgah National Forest
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From: Frederick MD
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From: Deep in the Pisgah National Forest
A question as well as a possible suggestion. When you say P-N you are talking about the neutral safety switch correct? If so and the ECM is not seeing this input is it possible that the ECM has different timing curves for park/neutral and on the go conditions? I’m asking the same about the AC clutch operation as well.
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From: Deep in the Pisgah National Forest
Thread Starter
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From: Deep in the Pisgah National Forest
I took a test run tonight and it ran great, crisp throttle response where I was getting **** before.
That is, until about ten minutes into it and my headlights started to dim. My voltmeter was getting very close to the red zone. With the voltage low all sorts of bad things can happen to a CCC system, so I'll say that this thread has run its course. Problem solved. Onto the next one.
Many thanks to all who contributed.
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It's was that, plus a vacuum leak, and probably some weak electrical connections....
Also, something is blowing my 20 amp gage fuse. I've replaced it twice now. It powers the check engine light and that goes to terminal G at the ECU.
Last edited by Yadkin; Jun 2, 2020 at 10:08 PM.
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These computers are stupid. They just do what they were programmed to do.
it's programming "assumes" all parameters are as new.
If the EGR relay fails, it doesn't know. It thinks it's doing it's thing.
If the AIR bypass valve fails, it doesn't know.
If you remove all the stuff, it "thinks" its still there.
If the car thinks the smog pump is working, it alters the fuel ratio because it believes the reading is diluted. If it's really not, it doesn't know.
IF the voltage is low, well, you get the idea
it's programming "assumes" all parameters are as new.
If the EGR relay fails, it doesn't know. It thinks it's doing it's thing.
If the AIR bypass valve fails, it doesn't know.
If you remove all the stuff, it "thinks" its still there.
If the car thinks the smog pump is working, it alters the fuel ratio because it believes the reading is diluted. If it's really not, it doesn't know.
IF the voltage is low, well, you get the idea
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From: Deep in the Pisgah National Forest
Looks like my alternator is no good. It was replaced by the PO, who got cute and replaced it with a reman from an old Delco core 1100497-37. I looked it up. It's been superseded 8 times, and the current version is 70 amps. Napa lists a reamn at 37 amps, same as the last two numbers on my part, so that's probably what this one is putting out.
I read the amperage it with my clamp on meter with lights and fan on and it's putting out 34 at idle. 13.6 volts. Raise the RPMs and my amp meter goes to zero- I don't know if that is an issue with my meter.
At idle I turn on the HVAC fan and the dash voltmeter goes below 13. Add in headlights and it goes further down. Add in highs and it's close to the red zone.
Voltage drop from the alternator is 0.3 volts on the positive side and 0.03 on the negative. That's a little high on the positive side but still tolerable.
I fully charged the battery last night. Turn the car off, leave the high beams on for 5 minutes then turn them off, and the voltage is at 12.6. That's not the problem.
Just ordered a new 85 amp from Autozone. They list a 63 amp "without rear defrost". Mine has that. It also has AC, both which require the bigger alternator.
I read the amperage it with my clamp on meter with lights and fan on and it's putting out 34 at idle. 13.6 volts. Raise the RPMs and my amp meter goes to zero- I don't know if that is an issue with my meter.
At idle I turn on the HVAC fan and the dash voltmeter goes below 13. Add in headlights and it goes further down. Add in highs and it's close to the red zone.
Voltage drop from the alternator is 0.3 volts on the positive side and 0.03 on the negative. That's a little high on the positive side but still tolerable.
I fully charged the battery last night. Turn the car off, leave the high beams on for 5 minutes then turn them off, and the voltage is at 12.6. That's not the problem.
Just ordered a new 85 amp from Autozone. They list a 63 amp "without rear defrost". Mine has that. It also has AC, both which require the bigger alternator.
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From: Deep in the Pisgah National Forest
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