Problem With My 67 MUSTANG
 

ok, first off here is my mustang,
<img src="http://www.users.qwest.net/~mendezralph/Mustangsmall.jpg">
it's a 67 coupe with a L6 200 and a c4 tranny. The problem I am having is that it runs fine when it neutral or park, but as soon as I put it in gear, the engine performance suffers and it sounds like it wants to die. put it back in neutral, runs like a champ. also it has died when it has been in drive, especially when coming up to a stop sign. Anyone have any suggestions on what to do? I just rebuilt the carb, it's a Ford 1100 1bbl with automatic choke. Any help is greatly appreciated.

Maybe your tranny or differental is causing unneeded friction and causing your car under load....jack up your car and spin your rear wheels and see if they turn freely. Worse comes to worse your tranny might need a rebuilt. Possibly could be a messed up torque convertor?

thanks, will look into that, any other suggestions for anything? Want a list of all possible things. I was thinking of the torque converter myself.

It sounds like your idle is set too low. Does this happen more when the engine is cold?

Otherwise, I'd guess the torque converter. Even if that's bad though, I think a temporary fix would be to just raise the idle anyway.

A transmission or differential problem couldn't affect anything while the car is stopped.

Sweet car...


:)

It's nothing with the idle, I know that. I raised it up to about 1500 rpms at idle, and it does the same thing. But ya, I'm really leaning towards the torque converter now.

Could be ignition problems. When was the last tune up? Checked the timing lately? Have you done the darkness test to check for arcing? Have you done a compression test? How many miles on the timing belt?

Just a couple of thoughts. I hate these kinds of elusive problems. Could any number of things.

Check the output of your alternator as well.

Ignition problems, we were having ignition problems, it was with the distributor coil, we got that fixed though. The timing I don't think is a problem, but I am also going to check it. And there is no arcing. Compression test shows up fine. 120 - 140 on each cylinder, for the brand new motor in 1967 it was supposed to be 150 each, so for the original motor and no rebuild on it, that is pretty damn good. The timing belt was replaced right before we got it, so under 100. Alternator output is fine we ran the charging system test and it shows up good, same with the battery.

Is power ok once you get moving?

I have a '71 fastback with a 302, and I have some of the same problems. It doesnt die but it feels like it might when I come to an idle, but if I shift into nuetral or park it runs great. I need to get my C4 rebuilt anyways and the guy at the tranny shop told me that the new Torque Converter hes gonna put on should fix the problem. We'll see how that goes. Nice car!

oh nice. sounds like i really should get a new torque converter, and the power is good electrically if thats what you mean, horsepower on the other hand. no. sounds like new TC is in my near future

Sounds to me like you have vacuum leak somewhere, also check the vacuum modulator on the transmission. Pull the vacuum hose off the modulator, It should be dry, If you have trans fluid In the hose, change the modulator.


Quote: BigBlue66

Have you done the darkness test.

BigBlue Is correct ... Bad Plug Wires can cause this.

on the engine, I don't have a vacuum leak, the vacuum modluator I havn't checked yet, thanks for the idea. I think that would be a hell of a lot less time and money than a torque converter. Will check that as well.

Are you sure

It's possible you have a small hairline crack on your intake manifold, you will not hear the leak, and It's very hard to see. You may need to use a mirror to look underneath the Intake manifold.

Hook up a vacuum gauge to the Intake manifold, start the car, the gauge should read about 12 to 20 pounds. It should not fluxuate much, If it does, you have a leak somewhere. I've also seen that a broken or weak valve spring can cause this problem.

I mean I ran a compression and leak down test on it, there isn't a leak, I've done all the tests for it.

Try this forum :)

http://forum.doityourself.com/forumd....php?forumid=2

thank you

Thats why a Standard trans kicks ass:)






Man if you have done all them tests on it and can't find the problem I think its time to take it to a professional(unless your a mechanic yourself).

Actually me and my father run an automotive shop and are mechanics ourselves. And yes, I would have prefered this as a manual, but I didn't know how to drive a stick that well when I bought the car, but after having a stick to drive as my only car while we were working on this, it got to the point where I prefer manuals better. We messed around with the carb a little bit more today to smooth it out more, it helped a little, but we know the problem still isn't in the carb. I really don't want to spend the 4 hours to take the torque converter out yet, I want to see if it's anything else first, but it's looking like it's going that way.

I agree with Nomad, this seems as though there may be a vacuum leak somewhere. In some cases, older rubber vacuum lines are known to collapse in on themselves, which could also cause issues. Have you checked your fuel pressure?

ya, i had the problem before i rebuilt it.