Engine bog on highway

[psfr311]

Today I was driving down the interstate doing 70 sitting at around 2k rpm's. The engine started to shake suddenly and when I hit the gas it sounded like it was bogged down. If I slow down and gas it again it's fine at and above 2k rpm. No CEL. Any ideas where to start diagnosing?

 

[noJeepshere]

More info first, what are you driving? miles, etc

So, below 2,000 rpm, is it rough? Only above it's smooth? You also make it sound like a one-time deal. Initial impression is the fuel system. Can you test the fuel system pressure? A good pump will run about 50 psi idling. How long has it been since the fuel filter was changed?

 

[SunlitComet]

better put out more pressure then that.

 

[psfr311]

At 2k rpm doing 70 it bogs. If I drop down to let's say 55 and have it at 2k rpm it's fine.

99 Tahoe 4x4 143k miles. 5.7

 

[psfr311]

Fuel filter is about a year old

 

[95TahoePA]

Just a thought... My Jeep did the same thing and i found it to be my catalytic converter. But I would check your Fuel Pressure first before diving into a $250+ part.

 

[elsamurai]

my old caprice would do that at random. thought it was the torque converter till i found out the engine was just starting to miss real bad occassionally. when was your last full tune up?

 

[psfr311]

Year and a half Atleast. I need to do one

 

[SunlitComet]

of you have delco recommended parts on there you do not need to change your plugs for a 100,000 miles. did you get a "flashing" cel when it started to bog hard?

 

[psfr311]

No I have gotten the flashing cel before. I was doing highway speeds also then but the engine did not bog like it this time.

This time I got no cel at all

All parts are Delco. Maybe I'll just replace the cap then


Speaking of the flashing cel the time it happened it flashed for 5 or so seconds then was just steady on. Then went away all together a couple days later so I never investigated it more.