84 vette lacking power
Thread Starter
Instructor
Joined: Oct 2012
Posts: 120
Likes: 0
84 vette lacking power
Hi guys, just hoping for some more help. I have a 84 corvette. Just got it on the road. I changed the spark plug wires and I thought I put them on correctly, as I changed one by one hoping that it wouldn't be possible to mix them up. Well I drove it on the highway today and it is totally lacking power. Like no acceleration, it hesitates pretty badly, and it just doesn't move like I know it should be able to. Any ideas? It feels like it isn't running on all the cylinders... does this seem to be the issue? Thanks all in advance!
Pro
Joined: Oct 2012
Posts: 613
Likes: 3
Start with the basics you should be able to google the ignition wiring online to see where all the wires go.
If you just got your 84 go through everything !!!! to ensure that you will have a reliable running car.
For example i started here when i got mine
Go through ALL the ignition components,
http://forums.corvetteforum.com/c4-t...er-wobble.html
If you don't already have one get the Factory Service Manual or sometimes called Shop Manual.
Then go through all the fuel related components testing to ensure they are all working, it's harder on our 84's because there is no shcrader valve to test fuel pressure so you will have to fabricate something.
http://forums.corvetteforum.com/c4-t...-us-noobs.html
And of course your timing needs to be checked as well
http://forums.corvetteforum.com/c4-t...-now-what.html
This should get you started, report back with your results so we can help you more!
If you just got your 84 go through everything !!!! to ensure that you will have a reliable running car.
For example i started here when i got mine
Go through ALL the ignition components,
http://forums.corvetteforum.com/c4-t...er-wobble.html
If you don't already have one get the Factory Service Manual or sometimes called Shop Manual.
Then go through all the fuel related components testing to ensure they are all working, it's harder on our 84's because there is no shcrader valve to test fuel pressure so you will have to fabricate something.
http://forums.corvetteforum.com/c4-t...-us-noobs.html
And of course your timing needs to be checked as well
http://forums.corvetteforum.com/c4-t...-now-what.html
This should get you started, report back with your results so we can help you more!
Melting Slicks
Joined: May 2007
Posts: 2,075
Likes: 109
From: Longmont Co
If you did them one by one you should be OK there. If you have an inductive timing light you could hook it up to each wire as it idles to see if they are all firing. Does it run worse than it did before you "fixed" it?
Melting Slicks
Joined: Feb 2008
Posts: 2,384
Likes: 56
From: West Chester PA
St. Jude Donor '09 thru '25
Hi guys, just hoping for some more help. I have a 84 corvette. Just got it on the road. I changed the spark plug wires and I thought I put them on correctly, as I changed one by one hoping that it wouldn't be possible to mix them up. Well I drove it on the highway today and it is totally lacking power. Like no acceleration, it hesitates pretty badly, and it just doesn't move like I know it should be able to. Any ideas? It feels like it isn't running on all the cylinders... does this seem to be the issue? Thanks all in advance!
Instructor
Joined: Mar 2013
Posts: 126
Likes: 0
From: Gay WV
You say you just got it on the road,.How long has it been since it was in use before you got it? Your problem might not be the spark,or firing order..If it has dead gas,or had been setting around nearly empty,and drawing moisture in the tank is possible...If you've got good thick rubber gloves you can pull one wire at a time while motor is idling you should hear a little difference in your idle..you should also hear the spark jumping like a ticking noise if you hold the wires close to the plug or distributator
Thread Starter
Instructor
Joined: Oct 2012
Posts: 120
Likes: 0
Start with the basics you should be able to google the ignition wiring online to see where all the wires go.
If you just got your 84 go through everything !!!! to ensure that you will have a reliable running car.
For example i started here when i got mine
Go through ALL the ignition components,
http://forums.corvetteforum.com/c4-t...er-wobble.html
If you don't already have one get the Factory Service Manual or sometimes called Shop Manual.
Then go through all the fuel related components testing to ensure they are all working, it's harder on our 84's because there is no shcrader valve to test fuel pressure so you will have to fabricate something.
http://forums.corvetteforum.com/c4-t...-us-noobs.html
And of course your timing needs to be checked as well
http://forums.corvetteforum.com/c4-t...-now-what.html
This should get you started, report back with your results so we can help you more!
If you just got your 84 go through everything !!!! to ensure that you will have a reliable running car.
For example i started here when i got mine
Go through ALL the ignition components,
http://forums.corvetteforum.com/c4-t...er-wobble.html
If you don't already have one get the Factory Service Manual or sometimes called Shop Manual.
Then go through all the fuel related components testing to ensure they are all working, it's harder on our 84's because there is no shcrader valve to test fuel pressure so you will have to fabricate something.
http://forums.corvetteforum.com/c4-t...-us-noobs.html
And of course your timing needs to be checked as well
http://forums.corvetteforum.com/c4-t...-now-what.html
This should get you started, report back with your results so we can help you more!
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Thread Starter
Instructor
Joined: Oct 2012
Posts: 120
Likes: 0
It seems to run worse since i changed the wires... I must have them on wrong, but I dont understand how if i did em one by one... does it matter if I maybe mixed up the wires (like the length)? thanks!
Thread Starter
Instructor
Joined: Oct 2012
Posts: 120
Likes: 0
You say you just got it on the road,.How long has it been since it was in use before you got it? Your problem might not be the spark,or firing order..If it has dead gas,or had been setting around nearly empty,and drawing moisture in the tank is possible...If you've got good thick rubber gloves you can pull one wire at a time while motor is idling you should hear a little difference in your idle..you should also hear the spark jumping like a ticking noise if you hold the wires close to the plug or distributator
Pro
Joined: Oct 2012
Posts: 613
Likes: 3
It's possible if you did put the wires on correctly make sure they are all pushed in on the spark plug sometimes they are not on tight, you should hear a slight click when they are on.
Also it's possible you may have accidently disconnected a vacuum line while installing the wires, check the map sensor vacuum hose to make sure it's on tight, it's the hose that runs from the back of the intake manifold to the firewall on the drivers side to a small black box.
When i installed my wires i disconnected it accidently car ran like crud, plugged it back in only to get a CEL on the map sensor it was bad so i replaced it made a big difference.
Also it's possible you may have accidently disconnected a vacuum line while installing the wires, check the map sensor vacuum hose to make sure it's on tight, it's the hose that runs from the back of the intake manifold to the firewall on the drivers side to a small black box.
When i installed my wires i disconnected it accidently car ran like crud, plugged it back in only to get a CEL on the map sensor it was bad so i replaced it made a big difference.
Instructor
Joined: Mar 2013
Posts: 126
Likes: 0
From: Gay WV
When we were kids we used to test lawn mowers for fire by grabbing the terminal,and cranking it .The term we used for it may be offensive to some..LOL.....Sometimes people leave the distributator a little loose..you don't reckon it turned on you ?....If it's them wires that you put together, I don't care for them..If all else fails put some of your better looking wires back on and see if it makes a difference ..I have had wires crossed in the past,and always knew it right off the bat..backfires real bad while cranking...I don't know if you changed plugs,I assuming that if you did you gapped them,but I have cracked them putting them in too,and if you dropped one,or banged it into something while putting it in, you may have the ground touching the electrode,and it wont fire,did you have much of that old white scaley corrosion on you cap?..When you say it hesitates,does it sound like it's drawing air,or does it stumble,and sputter?
Thread Starter
Instructor
Joined: Oct 2012
Posts: 120
Likes: 0
It's possible if you did put the wires on correctly make sure they are all pushed in on the spark plug sometimes they are not on tight, you should hear a slight click when they are on.
Also it's possible you may have accidently disconnected a vacuum line while installing the wires, check the map sensor vacuum hose to make sure it's on tight, it's the hose that runs from the back of the intake manifold to the firewall on the drivers side to a small black box.
When i installed my wires i disconnected it accidently car ran like crud, plugged it back in only to get a CEL on the map sensor it was bad so i replaced it made a big difference.
Also it's possible you may have accidently disconnected a vacuum line while installing the wires, check the map sensor vacuum hose to make sure it's on tight, it's the hose that runs from the back of the intake manifold to the firewall on the drivers side to a small black box.
When i installed my wires i disconnected it accidently car ran like crud, plugged it back in only to get a CEL on the map sensor it was bad so i replaced it made a big difference.
Thread Starter
Instructor
Joined: Oct 2012
Posts: 120
Likes: 0
When we were kids we used to test lawn mowers for fire by grabbing the terminal,and cranking it .The term we used for it may be offensive to some..LOL.....Sometimes people leave the distributator a little loose..you don't reckon it turned on you ?....If it's them wires that you put together, I don't care for them..If all else fails put some of your better looking wires back on and see if it makes a difference ..I have had wires crossed in the past,and always knew it right off the bat..backfires real bad while cranking...I don't know if you changed plugs,I assuming that if you did you gapped them,but I have cracked them putting them in too,and if you dropped one,or banged it into something while putting it in, you may have the ground touching the electrode,and it wont fire,did you have much of that old white scaley corrosion on you cap?..When you say it hesitates,does it sound like it's drawing air,or does it stumble,and sputter?
Melting Slicks
Joined: May 2007
Posts: 2,075
Likes: 109
From: Longmont Co
You wouldn't notice a difference in the length. Again, check that each wire is firing. If you have an induction timing gun this is real easy. If not remove the wire at the plug (one wire at a time, as someone else has already said) and check for spark jump. Make sure all wires are on firmly on both ends.