no power at 5th gear

[rogelioifmradio]

Hi, despite the grinding on my tranny i found out yesterday that when i reach 5th gear the car looses power.. i mean.. the accelerator pedal is full throttle but there is no traction.. no power..no revs..no more than 55 miles per hour and the speed starts to drop. is like there is no gasoline injection at all...it only happens on 5th gear.. what should i be checking for? what can be wrong?

[Mikestang]

No other gear? Strange, plugged exhaust?

[rogelioifmradio]

No other gear? Strange, plugged exhaust?

No other gear... Its Like the car had a SPEED limitor.... No revs, no speed And no traction... Like if IT wa sin neutral.. But without reving

[Hissing Cobra]

Do you have any teeth on 5th gear?

[rogelioifmradio]

Do you have any teeth on 5th gear?

How could i know? Do i have to open the tranny for that?

[Hissing Cobra]

I would think so. If you've got grinding gears then I would imagine there's a possibility of some missing teeth. Either that or it's not even engaging 5th gear. The only way to know for sure is to pull it out and take it apart. It's not hard to pull them out. I've had mine out in 45 minutes flat.

[83gtstang]

What is your timing set at? Have you checked your distributor, maybe the vacuum advanced springs or something.

[gr79]

Had a 85 2.3 FI Ranger with a similar symptom.
Noticeable lack of power in 5th while cruising up a medium freeway grade.
Flooring the pedal did nothing but lose more speed.
Had to drop down to 4th to keep up.

Found the air duct flap in the air cleaner intake duct was inop.
Would not let cool air into filter box.
Only hot air from exhaust manifold via round flex duct.
Disconnected and plugged vac line to the air intake duct flap mechanism.
This defaulted the flap to fresh cold air only; no heat from the exhaust manifold via flex tube.
Problem solved.
Cost= 0.00
Plus much better fuel mileage.

[rogelioifmradio]

Had a 85 2.3 FI Ranger with a similar symptom.
Noticeable lack of power in 5th while cruising up a medium freeway grade.
Flooring the pedal did nothing but lose more speed.
Had to drop down to 4th to keep up.

Found the air duct flap in the air cleaner intake duct was inop.
Would not let cool air into filter box.
Only hot air from exhaust manifold via round flex duct.
Disconnected and plugged vac line to the air intake duct flap mechanism.
This defaulted the flap to fresh cold air only; no heat from the exhaust manifold via flex tube.
Problem solved.
Cost= 0.00
Plus much better fuel mileage.

Please.. where in the car is that?.. i beg my pardon for my ignorance..it sounds like is something i can do by my self.
are you talking about the air intake?, i had installed one of those conic low restriction air filters instead of the stock one..
would be very helpful if you send a pic or a diagram..
thanks in advance..

[83gtstang]

Is your car carberator or fuel injector?

[rogelioifmradio]

it is an 1986 mustang svo, its fuel injected turbo..

[PaceFever79]

Can you get a friend to record a cell video while you drive?

That might help us understand the problem.

[cb650]

Plugged converter?

[svono50]

It sounds like you have issues when the engine is under 'full' load, which is tough on the ignition system to get things fired off. First, make sure your ignition system is up to snuff (i.e.- good cap, rotor, wires and plugs). Plugs should be copper units (NO platinum plugs please) and gapped to ~0.030".

Next, are you seeing any boost at all and if so, how much at what rpm in 5th gear. If none, what are you seeing in the lower gears?

Check to make sure your support wire is in the hose between the VAF and turbo inlet. If it is missing, the hose could be collapsing choking off the intake.

Check your VAF flapper door to make sure it isn't stuck or getting stuck with some debris sitting on the floor of the VAF.

You could also remove the air filter cover and air filter and take it out for a test drive to see if there is something in front of the VAF causing airflow issues. Running without these for a test drive won't hurt anything.

What kind of gas are you running?? Better be premium (i.e.- 91 octane or better). If so, how old is the gas? When was the last time the fuel filter was changed? Have you checked the fuel pressure while running it around? You can get one of the loaner guages at most auto stores and tape it to your windshield for checking it while driving...DO NOT run it inside the car please!