OK, so I am loosing out on power. I have a racing beat header to straight pipe to stock muffler, slightly ported intake manifold with stock nikki (mechanical secondaries), emissions removed, a/c removed, and second gen direct fire.

The exhaust has a few leaks in it from poor welding that I tried to patch with some kind of exhaust leak fix thing. Problem is it is burning it off, so it is smoking and smells like ***.

About a week ago, I started having trouble starting it, (never had trouble before), and it would die if I didn't keep it revving over 1.8-2.0 rpms. After about 4-5 minutes of running it will stay running but it idles rough and will die if I try to take off very quickly. It revs kinda slow, but even in third gear I just got it going 7200 rpms going uphill, just took a little bit longer.

I have messed with the idle mixture screw but it didn't help smooth out the idle at all. I also pulled the spark plugs and they were kinda black (?!?!?). I also tried switching the plug wires from the second gen coil to the dizzy, still no improvement.


I need some ideas. PLEASE PEOPLE!!!!!!!

 

My money's on a vaccume leak somewhere.

 

I can't find a vaccum leak, anyone else?

 

Fuel Filter

 

Well, maybe youve got some problems with the carburator. Its got a million little parts, but if you are very patient, even an amature can easily rebuild ,and or give it a thorough, cleaning.

 

I rebuilt the carb 5 or 6 months ago and it has given me no problems at all till now. Crap I am out of ideas....

 

Have you verified that you have both leading and trailing ignition? This is probably the simplest thing to check/eliminate. Good luck...

 

I have not yet done this but from what I understood, the trailing is mainly for emissions reason, and simply burns off whatever little is left?? But I will do that tonight when I get off work.

 

Yeah, I'm not so concerned with the trailing as I am the leading. Loss of the trailing would hardly be noticeable (if at all). Good luck..

I'm not exactly convinced that this is your issue, but it could very well be. Besides, its so damn easy to eliminate you might as well check it out. You might get lucky.

 

do the plugs smell like gas? are they wet? any oil on them?

since this just 'suddenly' happen, i'd vote vacuum leak. possibly bad shutter valve or the like. spray carb cleaner around the carb area and see if you notice the revs rise or not.

 

My car does the same thing on a cold start, if I start it it's very hesitant to get up to the clear idle spot (2,500 RPM) so I have to gas it when I do it sounds like the clutch fan engages and it idles fine (with a lot of smoke sometimes, only if its cold out side...mmm exhaust leak on mine at the CAT which I think is robbing me of big power, gf over did her cell phone and got me a nice little $200 in my mail! >:|)

- Tech

 

Well, I don't have a shutter valve, but I will try again to see if I can find a exhaust leak (not right now it is raining). But, is that true that with an exhaust leak you will have hard starts and less power?!?!? I do have multiple exhaust leaks, small but still there.

 

could you have a leak with your ACV plate? Ive had this problem...

 

How many miles? Hows it start when its hot?

 

The ACV plate might be leaking... and it has 170000 miles on the stock motor. When it is hot I have to pump the gas 2-3 times before it will start. It is worse when it is cold, (won't idle), but ever when it is hot it idles rough and ?misses? so it will idle around 750-800 but it doesn't run right. It sounds like the ACV mabye just a little...have to find out.

 

Yeah check the acv block off plate and your intake manifold gasket for vaccum leaks. I've had the acv leak before and it was a pain in the *** to get the car started. Good luck.

 

ill almost put money that its a fuel filter getting slightly clogged..

 

I just replaced the fuel filter 2000 miles ago, and it doesn't bog at all even after running it under hard load, it is at all rpms, it actually gets seems to get slightly better the higher rpms I go.

 

Man thats crazy I'm having the EXACT same problem and I can't figure out what it is either, and my engine only has 700miles on it and it was running great i gave it a little gas on a straightaway and bam just started running crappy losing power not starting good. I was wondering if maybe it was the ignition lead as well but I'm gonna have to check the acv block off plate keep me informed if you find anything. Oh and I know its not the fuel or vac leak either well at least on mine because the fuel system and vac lines are all new I feel your pain.

 

Did you ever verify that you have spark on your leading ignition?

 

Yup, it seems to be leaking just slightly from the acv block off plate, it gave it a sort of lumpy idle, but as I revved it, it leaked more and more.... Yea, I'm a dumbass.

Kinda off the topic but I think I fried my starter. The problem is, it was engaged as I drove it about 3 miles to get back home. It made a sort of grinding noise all the way home. So would it be, just repace the starter or could I have damaged anything else? Just replacing the starter is quick and easy as I have axcess to a lift.

One more question, can I push start it with the starter not working, or could that damage it worse? The wife needs her car next week...

 

Running the car like that could damage the flywheel.....

 

Yea, I haven't had time yet to take the starter off (12-14 hour days at work), but when I tried to turn it over the damn thing just made a whirring noise, so I think the teeth are gone. Don't know what else that may have done though.