black83camaro

Hey everyone, I have a 1983 2.8. When I accelerate at a fairly light throttle the car pulls just fine, Idles high but no skipping or misfireing at idle. When I give it any sort of throttle over an 1/8 it falls on its face and will lose all power. The RPM's will slowly climb and be smooth, but its almost as if there is no power past this point. I got the car and the vacuum hoses are a mess, Manifold line is completely rotted off and is non existent, couple vacuum hoses that are not going to anything, its just a mess. This being said I have checked for leaks all over the motor except these lines that I have no idea where they go. I feel as though the motor is running to lean? I will be checking the timing this weekend, although I was hoping someone would shed some light on the subject? Things I could look at specifically?

Would places even carry lines like this anymore? does anyone know the diameter and threads per inch going into the manifold? I would like to just keep it stock for now and fix the problems I have. Pulled the plugs and they all look clean and gapped correctly, changed them. Spark plug wires look okay, no cracks or anything.

Any help is appreciated!

TomP

Originally there was a sticker on the underside of your hood with the vacuum connections, is it still there? Nobody makes the lines anymore, but they sell 1/8 and 3/16 vacuum hose, and t-fittings, and adapters, etc- you'll just be making your own.

They sell the hard plastic tubing in rolls, again, you'd cut it to length and use adapters (or bits of hose) to connect the tubing to the car. http://www.summitracing.com/parts/rn...FSdn7AodzHcAEQ

TomP

One more thing- how does it drive? Is it driveable or does it hit that wall and won't accelerate any faster? If it hits a wall it could be a clogged catalytic convertor. Had a friend with an '83 Camaro that happened to. I did the test drive- it was so strange to push on the gas and zero happened.

black83camaro

Ill have to check under the hood for the diagram, still trying to make sense of all the emission devices on it before I start reconnecting things. It doesnt hit a wall per-say, it will accelerate when I apply under 1/8 throttle. I can go on the highway with it but I have to prepare and accelerate long ahead of time for hills or ill find myself going 45 up it.. I could drive it regularly, with the high idle, but I would get poor MPG's, not to sure on how much but I know its below 22. Never took the MPG, I have a daily driver and I only cruised with my Camaro. Once I get home this weekend Ill take a gander and take inventory of everything that seems out of place.

Im not to sure if the high idle is just due to some vacuum hoses not being connected properly or maybe the carburetor is gummed up and needing rebuild? surprisingly enough I seafoamed it once I bought it and it didnt blow one puff of smoke.. oil looked brand new when I changed it and coolant looked good, How lucky is that? I feel as though the high idle is due to a vacuum but I need to know what Im looking at more.

TomP

Well you can't have vacuum hoses just unconnected, fix that first... might be able to search on here for a vacuum diagram too.

And that acceleration sounds like hitting a wall- if you floor it, nothing happens right, car keeps moving along as if you didn't floor it?

TomP

Did the search for you because I was curious, check this out, Chevy86 IROC-Z put up all the diagrams, your '83 is in message 26 on page 1, that was cool of him!! https://www.thirdgen.org/forums/tech...iagrams-i.html

black83camaro

Thanks for your time and research! When I get the chance im going to search for the Vacuum diagram on the hood also, and print out the diagram you found and make sense of the situation. This may be a dumb question but if I can not find exactly where a vacuum hose goes to, could I simply plug up the remaining open hoses and see what it changes? I am unsure if this would cause any sort of damage to the engine. Would this affect the timing at all? due to the system sending certain information to the computer changing the timing? I know I do not have a vacuum advance carb I have an electronic one, I am just curious if this would cause the computer to lean or make the mixture richer.

I feel as though I may have mislead you by saying it falls on its face when above 1/8- full throttle. Once I apply more throttle, that is over 1/8 the car will still accelerate just slower. Im new enough to not know exactly what a car is doing just by listening to it but it seems as though it is not firing correctly . I do not believe my Catalytic Converter is the culprit but im not going to simply rule it out.

Sometimes my 2.8 has a "good day" and it will pull at full throttle as well as 1/8 throttle and less. This situation is rare though and only happened a couple times, not sure if this can help locate the problem. It is not a constant situation so I feel as though it is of no help but just food for thought.

How exactly does the manifold line to the EGR connect to the EGR valve? Mine was broken off and just the nut is there, is there any sort of replacement I can get for this one hard line or can I get away with just some sort of flared tubing?

Again Ill be checking everything this weekend and ill keep you updated. I appreciate the help!

TomP

No problem, we should all be able to help you get running again! Yeah the catalytic convertor check isn't fun to do- it's technically easy but a lot of fighting to get the rusted cat off the rusted exhaust pipe, then you go for a drive to see if the problem is gone. Could also look inside the cat with a flashlight, it shouldnt' be empty. If it's empty then either someone gutted it, or, the pieces blew out into the rest of your exhaust and could be blocking the pipe or muffler.

Another option is to just cut the pipe in half. You can rejoin it with welding, or, with one of these tough clamps: http://www.summitracing.com/search/p...amp-butt-joint They're much stronger than using a soda can and some regular exhaust clamps I used one to replace my rotted out intermediate pipe (cat-to-muffler) without dropping the rear axle, cut the new pipe in half, put the two pieces in place, and clamped them together with the band clamp midway under the car.

For the EGR I'm not sure, someone else may know? Would need to see a picture. If it gets hot then yes metal tube is probably your best bet...

black83camaro

Just thought I would give you an update. I was looking over my vacuum lines when I found one of the main lines to the fuel vapor canister was off... must have no vacuum in the system what so ever. It runs a lot nicer now but the hesitation is still slightly there. Although it runs 50% better I think there might be another leak somewhere. I tried spraying brake cleaner on all the lines but could not find a leak anywhere. Maybe it was a combination of a few things? I took my mileage and i was about to get 28 on the highway which I was pretty impressed with. I thought my carb was running a little to rich because of the high idle, with the RPM's around 1300ish. Ill keep searching. I really appreciate the help TomP, Ill keep at it. What to look at next?