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Discussion Starter #1
Gentlemen: I have an '88 Chev. Suburban that I have owned for 13 years -- 350 TBI. Its always been well maintained and jumps with power. Recently after driving 20 miles with no problem, I started it to return home but barely make it. When I pressed the accelerator there was almost nothing -- like it was "sucking air" but no fuel. I barely made it home. I'm in the mountains of W.Va. about $100 tow away from a shop, so I'm searching for a home remedy.

I changed the fuel filter on the frame, but it made no difference.

Since then I've discovered something very curious that may identify the source of trouble.

At cold start up, the truck runs fine with normal power. But after 30-90 seconds (depending on the temperature) there seems to be some sort of idle "kick down", and then it is in its no power mode.

Does the computer by-pass some component during cold start-up that comes on-line after a minute? If so, this may be my gremlin.

Thanks very much for any thought you may have. You can e-mail me directly at [email protected]

Bob
 

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Sounds like the cat may be going bad. If the computer was shutting something down, it should light up the Check Engine Light.
 

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I'd say it was the computer going from closed circuit mode to open circuit mode, but as Gary said, it should be kicking the check engine light on if there were a problem with a sensor.
 

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Discussion Starter #4
Guys: Thanks for your thoughts. I double-checked the SES light and it is working when you turn the key "on", but no sign of lighting in connection with the power problem.

If it's the cat converter, would it make sense that this would cause the power problem all of a sudden? Also, why would there be that initial 30-90 seconds of good power at start up? (At the tailpipe, the exhaust sounds like it is flowing normally -- does that mean anything?)

Thanks for your further thoughts.

Bob
 

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run the motor and get her good and warm. then crawl under alittle on the pass side and look at the cat if it is Orange or red it might be the main issue (95% of the time this is true the other 5% is ignition issues) it maybe real hot.....mike
 

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a Ford F-150 I had the displeasure of driving up at camp one summer had a plugged catalytic converter. The truck had absolutley no power. I once had my foot on the floor trying to roll up an almost-unnoticable slope while trying to roll over a stick from a dead stop. I couldn't get the truck to move! I actually had to get a pull to a more flat section of ground before I could start moving under my own power, and then it was only at maybe 5mph on the floor. The catalytic converter was beet red after limping the truck back up to the shop.... So, a catalytic converter can DEFINITLEY cause a loss of power. Good news is that it doesn't sound like the cat's completley plugged, but it's on its way out... I'd get it checked/replaced pronto.
 

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Sounds like the cat may be going bad. If the computer was shutting something down, it should light up the Check Engine Light.
Check this first before you do anything else.
 
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