I need help... 1966 Mustang 6 cylinder won't idle and dies

robert_t_wallace · 12-06-2012, 12:47 PM

I have a 1966 "T" code mustang that has has a 2bbl Webber DG98 and manual choke with the Clifford 2bbl adapter, Pertronix, Classic Inline Dual Headers..

Car sat from 2006 in a garage and had not been started... I replaced radiator, water pump, thermostat, belts, hoses, plugs.. Drained all the fluids and replaced.. had the carb rebuilt...

right now, the car needs exhaust and is just open headers. Muffler shop wants it idling so they can check for leaks..

car is very hard to start. When it does hit, it idles up and dies. Seems to like half choke after it does warm up to attempt to idle. I had a mechanic check timing and vacuum leaks. He said that I need to drive it for awhile, but don't buy that. I'm hoping the motor is good, but it does not smoke. I just can't get it where it is easy to start and/or idle. After the motor gets warm, you can wrap on the accelator and the car revs fine. ultimately, the car will idle ok when it gets warm/hot. When it is like this, the car does not seem to have any power or torque. It dies trying to get in on the trailer and requires 2 people pushing it from behind.

What are you thoughts? Anyone in the DFW area that can help

critter1212 · 12-06-2012, 03:10 PM

I am no expert but replacing the fuel filter helped resolve some but not all my idling issues. Mine sat for five years and I am still working crud out of the fuel system after a couple months.

wareagle · 12-06-2012, 03:17 PM

Have you checked the accelerator pump test to be sure fuel is squirting in the venturis(?) when you accelerate?

cholcomb · 12-06-2012, 03:51 PM

If I walked up and started looking into this I first would look at the accelerator. I recently had my channel blocked in my carb and had to dismantle and drill out, could easily be missed on a rebuild. One of the symptoms was when I stomped on it would try to die. Now has plenty of power. Also I didn't catch the type Transmission. Auto/manual? fuel filter is a must, a clear one lets you see if fuel is getting into carb. Also but not likely the bowl might be out of adj. and starve you of fuel. These are just some quick thoughts. Double check ignition wiring for correct firing order?

cholcomb · 12-06-2012, 03:58 PM

Did you verify closed choke plate when you pull choke? I placed a paper clip over the side of the throat to keep plate open a very small a mount to test if the choke was set right, because the choke has to be just barely cracked, also you may and should adjust carb as the manual states to insure proper adjustment are made. Again just some rambling thoughts.

bartl · 12-06-2012, 03:58 PM

I can't tell you the number of times I've seen a car that won't idle on open headers. Slap an exhaust on and they straighten right out. Sometimes advancing the timing also helps. My guess, though, is that there is still some junk in the carb.

robert_t_wallace · 12-06-2012, 08:10 PM

Quote:

Originally Posted by critter1212

I am no expert but replacing the fuel filter helped resolve some but not all my idling issues. Mine sat for five years and I am still working crud out of the fuel system after a couple months.

I have replaced the fuel filter (added an inline clear one)and the fuel sending unit in the tank as it has a filter on it. I had the carb rebuilt, but did not replace the redline/webber fuel pressure regulator...

I can see the filter now and it does not look bad..

robert_t_wallace · 12-06-2012, 08:14 PM

Quote:

Originally Posted by cholcomb

If I walked up and started looking into this I first would look at the accelerator. I recently had my channel blocked in my carb and had to dismantle and drill out, could easily be missed on a rebuild. One of the symptoms was when I stomped on it would try to die. Now has plenty of power. Also I didn't catch the type Transmission. Auto/manual? fuel filter is a must, a clear one lets you see if fuel is getting into carb. Also but not likely the bowl might be out of adj. and starve you of fuel. These are just some quick thoughts. Double check ignition wiring for correct firing order?

I had that same problem of die'ing prior to the carb rebuild. It now rev's fine, but is VERY hard to start (to the point it runs down the battery) and does not idle till the car is very warm.

It is a 3 speed...

put a new fuel filter.. a glass one.. it is full of gass

the firing order is as it was when I got it from the PO. It has a pertronix instead of points and I did replace the plug wires..one by one keeping the same order.. Do you know off the hand what the order is?

robert_t_wallace · 12-06-2012, 08:59 PM

Quote:

Originally Posted by bartl

I can't tell you the number of times I've seen a car that won't idle on open headers. Slap an exhaust on and they straighten right out. Sometimes advancing the timing also helps. My guess, though, is that there is still some junk in the carb.

I have taken it to "2" muffler shops and neither will touch it until it idles and drives.. They claim they need it to idle to check for exhaust leaks and to drive it on and off the ramps.

As a side not, the first shop wants $550 for dual exhaust, "X" pipe and magnaflows. The other wanted $750 for the same exhaust. Is this any good?

kevlarguy · 12-07-2012, 08:42 AM

Mine would not idle with the correct original carb.

My brothers a mechanic and has found cars that sit with the new gas have much more problems. The fuel is more likely to leave behind residue. So the idle ports, which tend to be very small orifices, will quickly get reduced in diameter. The idle jet that normally would only be about 3 turns off needed to be turned way out to effect any change. After a very aggressive cleaning with 2+2 the idle screw settled at about 3 turns out and it idled nice.
Also keep in mind that timing chain issue can also cause these symptoms. I would think you have carb issues given the car had been sitting. See if your adjusting screws are in the right area as that is a clue.

cholcomb · 12-07-2012, 08:48 AM

My next thought would be to mark your distributor and advance timing a little. Worse case scenario you just put it back where the marks are. I Adjusted mine just by sound, not very scientific but runs great. I will look for firing order. I take it you do not have a manual on this car, even a Haynes has some benefit. +1 on Kevlarguy

cholcomb · 12-07-2012, 08:55 AM

Firing order on inline 6 is 1-5-3-6-2-4. cylinder 6 is at the fire wall. hope this helps also did you go in with champion plugs or some special Platinum plug. Reason I'm asking some believe the newer style plugs do not work well with the older tech.

frontshadow · 12-07-2012, 09:02 AM

Possible Varnish in cab from setting (just had that problem on my 67....been sitting for about 1.5yrs...would not idle) AND it's true that many cars will not idle with open headers/manifolds. I'd attack the carb first, making sure that (with engine not running) you can see gas squirting into the venturi when you depress the gas pedal...just look over into the carb and watch for gas...if not, begin there first!

Explorer · 12-07-2012, 09:37 AM

Two things to add. If still using the stock LOM distributor with the Pertronix module, you have a mismatch in the vacuum signal provided by the carb to the vacuum advance on the distributor. You need the 68 or later style distributor with mechanical and vacuum advance. Second, try partially closing choke. If improvement, start looking for a vacuum leak.

robert_t_wallace · 12-07-2012, 01:02 PM

The carb does have a round redline fuel pressure regultor that is sold with the weber carbs and I did not do anything to that.. Do you think that needs looking at?