Like the subject says, when I'm on the highway and really givin' er, 1st and 2nd gear are fine, the engine runs all the way up the revs with no complaints. However, in 3rd when I'm climbing up the revs, around 5 or 5.5k RPM, the engine basically falls flat on its face and starts to run crappy, misfiring and what not. If I let off, it sorts itself out and I'm fine. If I'm not pushing hard at the top of 3rd, it doesn't give me any trouble. Also sometimes the gear shifter is kinda hard to get out of 3rd into 4th, I really have to give it a tug to get it moving. I don't know if the two are related, but having all the info is a good thing.

As far as my car goes, it's a '79 car with a 12A, RB header, no air pump/ACV or emissions solenoids. I've got a insulated CAI much like the one in Carl and Pratch's tutorial. Other than that, the car is stock, engine/carb wise.

Thanks for the help.

 

search for my thread....SAME problem...

1) change plugs-(this was my problem)

2) check fuel pressure-replace fuel pump and regulator (i also did this but wasnt the problem)


Brad

 

Cross posting eh?

 

If you are just cruising in 3rd or 4th, and then floor it, does it run fine?

If your filter is getting plugged up, it may only be obvious after pulling hard through 1st and 2nd. Basically, you're draining the reserve from the filter, and then the filter can't keep up with the demand by the time you hit 3rd. Anyway, sounds like you match my symptoms which were relieved with a new filter. Good luck!

 

Yep. I figured I'd get all the help I could muster. Anyhoo as it turns out, I somehow managed to FUBAR the vaccum advance on the dizzy when I took out the rats nest. With the vaccum pots open to the air and the nipples on the manifold capped, the car runs great.

 

S'what I was gonna say. That magic "5X00 rpm" number had "dirty filter" written all over it.
(Guess it's a magic number for a few things.)

Hiya, Moses.

 

Well, the problem returned last night when I was driving home from work. This time though, it was during cruise, the car just lost power and would die if I tried to give it any gas.

My bet is I have the evaporative controls hooked up wrong, since that's the only other thing that isn't plugged off.

Updates will follow.

 

Well it turns out that the fuel pump was kaput. I slapped a new one on and the stumble went away. It makes sense when you think about it, 'cause the car would run great in a straightaway through 1st and 2nd, and sometimes past 3rd, but usually by 4th, it would cab out and bog. If I lifted and gave it 10 seconds, the car would resume accelerating, albeit for a short time before the bogs came back. When I was autoXing, the sloshing that usually only starves the car on hard left turns was aggravated by the low float levels, causing bogs even after a short time of acceleration. Anyhoo, I did a couple of straightaway drags all the way into 4th and nary a bog was to be found, so I'll cross my fingers and hope that I've got it this time.

Funny how the fuel pump would start to cab out when I remove my emissions controls, but there you go... I just wish that I had figured this out before my flagging car pooched my first day of the regional two-day championship event.

On an unrelated note the pump I put in is a 4-6 PSI pump, that isn't too much PSI is it?

Hiya Sterling