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Old 02-14-2012, 11:14 AM
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Hey Chet,
Originally Posted by T-bucket23
Try this, when the truck is cold like in the am after sitting all night.
Open the hood and take off the air cleaner top.

Push the gas pedal to the floor and release then check the choke plate, it should be shut tight.
I tried that this morning and below is a quick 14 second video of it. The choke plate closed the first time I floored the accelerator pedal. I did it a total of three times.

Originally Posted by T-bucket23
Start the truck with the air filter top off and look at the choke plate, it should pop open 1/4" or so, If not the pull off is not working.

Let it run for about 5 minutes and look at the choke again once the temp gauge gets up to about 1/4 this may take longer if you have no thermostat. The choke should be fully open. If not then it is binding or junked up.

If you tap the gas at this point the fast idle cam should drop out.
I was able to run it for about five minutes this morning, but not long enough the to get the temperature up there. Outside temperature was approximately 45 degrees F this morning when the video below was shot.

In Case You Can't See the Video:

- Truck is started with no issues. Choke pull off operates immediately.

- Truck is allowed to idle/warm up until 2:25 mark, at which point the engine is revved to about 2,000 rpm, and can be heard bogging (a hissing sound can be heard). The fast idle cam is seen dropping. Fuel flow can be seen in the glass-cased fuel filter right before the carb as remaining steady.

- The engine is revved again about three more time up until 3:00 minute mark. The engine revs slightly higher, but the hissing and bogging can still be heard.

- Engine is revved again at the 3:35 mark, slightly past the 3,000 rpm mark. Hesitation and hissing still evident, but less so than before.

- Engine revved at the 4:25 mark to about 4,000 rpm. No hesitation or hissing heard.

- Transmission is slowly shift through every gear starting at 4:55 mark. Shifted back into Park at 5:05 mark.

- Engine revved again at 5:10 and 5:17 marks to 4,000 rpm. No hesitation or hissing is heard.

I did take the truck for a spin twice and it was running crappy again, despite me pulling over and revving it. I would have liked to have gone for a longer spin but, it was morning rush hour and I really didn't wana deal with all the middle fingers while barely pushing 30 mph.

I'll try to get another test run in before going to work, hopefully long enough to get the temperature up.


@ Augusto: Thank you for the heads up on testing the modulator. I will do that when I also end up replacing the rubber hose ends on the vacuum line.

Last edited by lt1silverhawk; 02-14-2012 at 11:28 AM.
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