problem with truck...back pressure?

[69ford99]

My truck has a super 40 flow on it and there is no pipe after the muffler and the muffler stops about at the back door on the truck. Ive been having a couple problems with the truck without any codes. When I turn the wheel all the way one way the truck dies, unless I give it gas. Also if im stuck in traffic and give it a little gas the tach jumps fom 1K-3K until I let off or give it more gas. Could it be not enough backpressure?

[jam92102]

I doubt it's back pressure. I ran for months with no piping or muffler after the y from the cats and never had a problem. No clue what it could be but I think you could rule out back pressure.

[TreySpooner65]

Its caused by a lack of fuel being delivered to the engine, could be a fuel filter, fuel pump, etc..

This happened to my mom on her car. I opened up her throttle body a little and presto. All done.

[Bigjht]

I'm not exactly very familiar with the trucks so someone please chime in and let me know if I'm wrong. Does this only happen when you are at a stop or very close to a stop? I had a similar issue with my Mustang and it was the IAC, idle air control, valve. It would do exactly like you said when it was starting to go bad and eventually it wouldn't idle at all when sitting unless you would give it some gas.

[nascar88ford]

These trucks don't have an IAC. They use the motor for the electronic throttle control to control idle. I would try cleaning the TB first.
-Matt

[Bigjht]

That's good to know, thanks for the correction.