I didn't say anything about codes, that was someone else.

What I am saying is that the battery cables are the cheapest place to start (all three of them), and they have more effect than you might think. I have been down this road before with a car that started fine and worked great until it got warm, and then idled fine but had no power, and when I shut it off it wouldn't start any more until it cooled down. Electrical resistance is a really hard thing to see and understand - it can work great when it's cold, and cause problems in systems you wouldn't think would be related when heat and resistance starts to build.

Please just replace the cables. The battery is going to cost you, but you've already acknowledged that it needs to be done. The cables are maybe $30 on top of that. If you wind up paying a mechanic $120/hr to diagnose things for four hours to find that I was right, you will be very upset. Just do it and know that's not the issue.
 
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Jeremiad

i appreciate all the help i can get. Thanks. and just so you know, this car has become my hobby car. shall we say... rebuilding from the inside out. eventually i intend to redo every wire and cable and gasket and whatzanots that can be changed without changing the whole engine. my end goal is for it to be a show car because ive never seen an 89 or any other 80s vette in any car show yet. im not done until the fat lady sings.
 
I have not had time to check a lot actually. i got a wicked cold on saturday and have been down since. 5 days later im just starting to come back to my senses. but i did run out in pouring rain to run the vette a few times to make sure it wasnt just a random drain on the battery. it started fine and ran at 14.3-6 volts. im starting to think on the deep end of things and want to search for any vacuum leaks before i start buying new sensors and relays. check the hind end of things as it were. if the wires and connections wernt good, it would never start and need a boost most of the time but thats not the case at all. so im voting out bad battery wires and connections. and yes ive visually inspected them so far. cant vouch for a shitty battery though. that will get tossed weather its good or bad just so i feel better LOL

but i did manage to get my editing computer running again so videos will come :)


I have to disagree a bit on that one Steve. Bad connections can be sporadic and are affected by temperature and vibration. Who hasn't had a beater at some point with a loose battery cable that had to be wiggled once in a while to get the thing to turnover rather than...click click click.
It's your show but I have to agree with @Jeremiad on this one. Basics for electrical is battery then connections on the feed out; including grounds and protection. And/or the supply in.

I liked the @AceCole post too. Makes sense, easy to check and cheap to fix.
Maybe it's just the cold medicine talking but unless I'm not getting the entire picture on what you are describing seems the boys are giving you good advice.

Hope you feel better soon and you get her sorted soon so we can go on a cruise.
 
its probably the cold or flu or whatever i have. ive been saying stupid things at work all day. im finding my brains logic center is totally malfunctioning.

lets just forget every thing i said yesterday. ill start on this again when my head doesnt feel like its about to explode.... or implode...
 
Interesting read. Whenever I read about any issues grounds seem to come into play. Simple first set would be to to identify, clean and tighten all grounds. Since the car had been sitting for 10 years corrosion would be my first objective to get rid of. the electrical connections between the MAF, relay and fuses would be a no brainer to clean and apply dieltric grease to but you've probably already been there. Good Luck and I will be watching for the win!
 
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Hi. I dont post here much but am an active cf member. for some reason i do not get emails when i reply in a thread from this forum.


anyway, OP, in your first post you said you have one issue left: surging idle.

then you said you had a voltage dropping.

then you said it was 13.8 i think.

Can you confirm? Cheers VT.

Are you in edmonton?
 
Hi. I dont post here much but am an active cf member. for some reason i do not get emails when i reply in a thread from this forum.


anyway, OP, in your first post you said you have one issue left: surging idle.

then you said you had a voltage dropping.

then you said it was 13.8 i think.

Can you confirm? Cheers VT.

Are you in edmonton?

Viking. Click on your name (top right), Click on preferences in the list that pops up for you and check or uncheck all the boxes for notifications or any other preferences anyway you like. We are actually working on a new noticification that blows your Vettes horn remotely every time someone mentions you in a forum post.... May be a while before the bugs are worked out of that one though... :rolleyes::Biggrin:
 
Im going to update since i finally got rid of this stupid flu i had. and it lasted 3 weeks.... anyhoo....

the vette will start fine.
after 2 blocks of driving the idle starts surging and the battery starts to drop at the same time.
if i park it, it has trouble starting again.

i know its a code 36 and i also know the battery has been in the vette since flipper was a minow.

when i get off my ass and save up some money, i will get into this project. at the moment i dont have the $ to put into it.

new mass airflow sensor prices are all over the board. from $183 - $825 depending on where you go. the relays are dirt cheap. the battery is not so bad either. i just dont have the means at this time so the vette gets driven daily around the neighborhood.

and yes im in edmonton.


anyway, OP, in your first post you said you have one issue left:

surging idle.

then you said you had a voltage dropping.

then you said it was 13.8 i think.

Can you confirm? Cheers VT.

Are you in edmonton?
 
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Honestly id love to get this thing on the road without having to worry about stalling out and failing battery and idle.

AND JUST GET ON WITH BEING A CORVETTE OWNER

and of course spending my time working on the cosmetics of the car.
 
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Honestly id love to get this thing on the road without having to worry about stalling out and failing battery and idle.

AND JUST GET ON WITH BEING A CORVETTE OWNER

and of course spending my time working on the cosmetics of the car.
All good Steve. We do what we can do and when we can do it. :thumbs:
 
Steve, sounds like u have more than one thing going on.

You do not have to spend money to diagnose. Then when u find your issue you may have saved enough.

Have you verified that the burn off happens when you turn the key off?

You will need to get it running and have a partner start the car, idle it for a bit a couple minites, then turn it off. you should see the maf wire light up red hot.

If it doesnt, boost the car with a set of jumpers and a second car and repeat the same test with the boosters still attached when shutting the c4 off. this checks if a weak battery is preventing the maf from getting enough voltage to burn off.

let us know if the filiment is getting red hot. apologies if you have already done this i may have missed it. if you did, what was the result.
 
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I'm not quite sure how to get my point across to you without being condescending or mean.

I've given you the cheapest possible (and the most important) options to start with, which is replacing all of your battery cables and ground cables. Your battery is optional in the beginning - it might be fine. But please listen to me, and replace those cables. I have seen all of this stuff happen more than just a couple of times on vehicles, and have seen others as well as myself spend hundreds of dollars replacing parts that didn't need to be replaced simply because of these wires. They are very inexpensive, but critical to every electrical system in your car. You can't tell just by looking at them.

If I'm wrong, you're out maybe $100 - but you're not really out, because you know they are good for many more years to come.

Edit: As I write this @VikingTrad3r has given me an idea. He suggests the idea of boosting, and given your description that the car doesn't want to start after it is warm/hot, are you actually able to boost it easily, or does it turn over slow and give the same or similar problems? This would be a clear indicator that you have electrical resistance happening.
 
Jeremiad
i agree that the wires may need changing. im not ruling that out. but that will not clear a code 36 off the dash warning. nor will a battery change. the car has never needed boosting nor did i say it has. it just gets very scary sitting at a red light. its also just a pain to start after running a while. not totally dead.

VikingTrad3r
The car has been diagnosed by a technician last fall. there is no burnoff happening at all. he has disconnected the MAF until it can be repaired. the mass airflow sensor has been cleaned but may be damaged. i found all sorts of shmutz inside it when i cleaned it last fall.

I will make it a point to address all your ideas and thoughts in a video summary. so you can all see for yourselves whats going on. i think the point of trying to describe in words whats happening is making everything totally convoluted to everyone.
 
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Jeremiad
its also just a pain to start after running a while. not totally dead.

This is what catches my eye. Please define "pain to start" so that we can understand better. To me, it means that the car turns over slow, like the battery is really low, and doesn't want to start. If you let it cool off for a few hours, maybe it will start easily again without even charging the battery. Try boosting it right away, and if it acts the same off a boost (turns over slow, doesn't want to start), then I would definitely look at the cables.

I know that you are concerned that the code is telling you something else, but please understand that the code is simply generated by the first system-critical device that fails to give back a proper reading of voltage and amperage. The 'computer' (ECU, OBD, etc) is dumb - it cannot intelligently diagnose where a system is failing or why. It has a set of expected parameters and when it doesn't see a match it reports the first thing it sees.

I don't want to get into a big complicated explanation of how the electrical system in your car works. I'm not an electrical engineer, and I would certainly say something wrong. Quite simply, everything in your car needs a 12 volt supply of power and a good flow to ground to work properly, and those cables are the foundation for every system in your car. Just having a cable and a connection is not enough. It needs to be able to handle the power required of it.

Think of it this way: Ever try to power your way through a fresh McDonald's milkshake? You can suck so hard that the straw collapses, and you only get a tiny bit of that cold deliciousness. The straw still works fine, you just need to back off of the flow expectation a bit. Your power and ground cables are similar. They can make a connection and allow things to work, but as work increases so does load. Electrical cables build load in the form of resistance (heat), which slows flow (impedance) until it can no longer meet its minimum requirements. This is your straw collapsing, and when you get a code.

I apologize if this sounds stupid. I'm just trying to find a way to speak in terms that a normal person can understand.
 
The 'computer' (ECU, OBD, etc) is dumb - it cannot intelligently diagnose where a system is failing or why

and this i totally agree with. 100%

hang tight my friends. i will make a video tomorrow.
 
This is what catches my eye. Please define "pain to start" so that we can understand better. To me, it means that the car turns over slow, like the battery is really low, and doesn't want to start. If you let it cool off for a few hours, maybe it will start easily again without even charging the battery. Try boosting it right away, and if it acts the same off a boost (turns over slow, doesn't want to start), then I would definitely look at the cables.

I know that you are concerned that the code is telling you something else, but please understand that the code is simply generated by the first system-critical device that fails to give back a proper reading of voltage and amperage. The 'computer' (ECU, OBD, etc) is dumb - it cannot intelligently diagnose where a system is failing or why. It has a set of expected parameters and when it doesn't see a match it reports the first thing it sees.

I don't want to get into a big complicated explanation of how the electrical system in your car works. I'm not an electrical engineer, and I would certainly say something wrong. Quite simply, everything in your car needs a 12 volt supply of power and a good flow to ground to work properly, and those cables are the foundation for every system in your car. Just having a cable and a connection is not enough. It needs to be able to handle the power required of it.

Think of it this way: Ever try to power your way through a fresh McDonald's milkshake? You can suck so hard that the straw collapses, and you only get a tiny bit of that cold deliciousness. The straw still works fine, you just need to back off of the flow expectation a bit. Your power and ground cables are similar. They can make a connection and allow things to work, but as work increases so does load. Electrical cables build load in the form of resistance (heat), which slows flow (impedance) until it can no longer meet its minimum requirements. This is your straw collapsing, and when you get a code.

I apologize if this sounds stupid. I'm just trying to find a way to speak in terms that a normal person can understand.


Some good advice there. I only wish I could throw a “Useful” “like” and a “LMAO”. Have to choose on here. No multiple reacting allowed.. @Nik.
So next time when pulling on a fresh shake and I get the collapsed straw or “impedance” I’m almost certainly going to get brain freeze or “throw a code”
The analogy is really quite good Jordan.

Steve glad you’re feeling better and as you can see you’ve got lots of help coming at you. Seems frustrating at moments but think of it this way.... the guys could just click on by. But they don’t because they really want to help.
I’m be back home in a week and maybe I can recruit a couple other corvette crazies to come over with me a have a look at your car with you. Much easier in person and maybe together we confirm the culprit and get this behind you. Going to be a crazy week with my car going in for some add ons and MITM with Cold Lake right after but let’s see what we can do.
 
Good to see the video Steve. Sends out a couple clues.
The flakey display really smells of bad grounds. Which is a sign of possibly more ground issues. This certainly could be the root cause of your loss of charging and rough idle once the car warms up and the bad ground is exasperated.
Your idle seems right cold and lowered to 800 as it was warming up. Seems ok and normal but a warmed up video would be useful to see how low it goes.

Anyway a good start and ya... nice looking car Man. Bird crap is the reality of leaving the car outside for 10 minutes so don’t sweat it.

Look forward to the next episode.
D
 
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