engine and drivetrain Car dies at 5 thousand rpms in 4th gear on the highway

[Guest Anonymous]

It poses a problem when I have to pass on the highway, considering how fast people drive around here. The car runs close to perfect in all the other gears as well as 4th up until that point. The car starts popping alot, I believe its coming from the engine itself. Also, the car just loses power and bogs down until the revs drop back down to about 4 thousand where it runs normally again. My car has dual weber 40 dcoes a 292 cam crane ignition, and a red coil. I kinda of wonder if it is some sort of a vaccum leak.

[c.d.iesel]

if the power is interupted in all gears above 4500 rpm -

it's your wizz-bang ignition box

Not Vacuum.

possibly the carbs............

[Guest Anonymous]

Its not interrupted in the other gears, just 4th.

[Guest Anonymous]

Actually, Im now running some really old stock plug wires, becasue the ones I bought from Bavauto were have a tendency to not sit right and fall off. Could that be a problem?

[c.d.iesel]

low battery voltage ? = YES

low alternator charging voltage ? = YES

poor engine to body grounding ? = YES

[ferrwrench]

Is it bogging and popping in all gears @ 5k & above, or just in 4th and cruising? When it starts acting up does it run hot? could be ignition box, grounds, loose connections, or just the box itself, or the fuel pump, cant keep up with flow demand at high rpm's..good sing is if it runs hot, bowl runs low and leans out carb...what kind of fuel pump. Is this a new problem (did it happen after you change something) or is it ongoing(just been chasing your tail...what has been changed). Get new plugs wires, you could just be arching cross cylinders..(probably just the case..).[/u]

[Pierre]

and not in 3rd, I suspect fuel supply. It could be as simple as a fuel filter.

I would try to rev it in 3rd, see how high it would go and STAY there for 15-30 seconds. If it's fuel, it will cut out there too. It's better if you can try it on a hill going up. The motor is drinking fuel faster than it's being supplied.

Good luck and let us know what happens.

[Guest Anonymous]

Thanks for the help guys. Currently, it only happens in 4th gear.

[schwarz75]

Check the condition of the lead from the fuse box to the + side of the coil, as the insulation and internals may be crusty with age and heat. Also, it could be that your coil is failing.

Lastly, check the wire from the coil (-) that attaches to the distributor. Not only is your engine under load in fourth gear, but there's more wind within the eng. compartment at those speeds, so if there's a crack in that wire from coil to distributor, it's more likely to flop around when your flying down the highway.

If all the above (wiring and coil) is good, then it's likely to be fuel starvation.

[Tiger75]

I changed my buddies plug wire and spark plugs. Did not helped. It turned out to be a plugged fuel filter.

[Durango_Dave]

Check too to see that the screen on the bottom of the fuel sending unit in the gas tank has not fallen off. If it has, it can slide around in the bottom of the gas tank and cause intermitten problems with fuel delivery.

[Guest Anonymous]

It poses a problem when I have to pass on the highway, considering how fast people drive around here. The car runs close to perfect in all the other gears as well as 4th up until that point. The car starts popping alot, I believe its coming from the engine itself. Also, the car just loses power and bogs down until the revs drop back down to about 4 thousand where it runs normally again. My car has dual weber 40 dcoes a 292 cam crane ignition, and a red coil. I kinda of wonder if it is some sort of a vaccum leak.

You are probably draining the float bowls under load at freeway speed, and maybe have a low volume pump or the pressure regulator isnt allowing enough fuel in. (you do have a regulator dont you?)

It would run fine in other situations and starve under the conditions you stated.