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Old 10-22-2003, 07:09 PM   #1
Tom
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I give up, know of any good mechaincs in phoenix?

I've tried everything. The problem is the truck runs like crap at idle and bogs when hitting the gas from idle. When its doing this crap the air/fuel ratio gauge is pegged so far lean its off the guage. I've checked voltage at the fuel pump and distributor, put a new fuel pressure regulator on, re-set carb to winter time settings, cheked all jets to make sure they werent clogged, new cap, rotor, wires and plugs, new intake, carb to intake, and carb top plate to carb body gaskets, plugged off all vaccum ports one at a time, replaced all vaccum hoses, set and checked timing 3 times, traced all wires to make sure none were pinched, cleaned out the air filter, and replaced the PCV valves. The worst part is at one point I decided F this and set the idle speed way high [well way high if it ran correctly, it was only normal 550rpm] and went for a drive. When I stoped the truck deisel'd after turning it off. I turned it back on and presto 1200rpm rock steady idle. Set the idle back down to normal 550rpm, again rock steady. Went for another drive, ran perfect. 15min later its crap again, and has stayed that way for days and over 100miles. I've tried everything, Im completley frustrated and I give up. Im actually throwing in the towel. I can't belive Im going to let someone else work on my truck, much less pay them to do it.

If anyone has anything else to check, or know of any good shops in pheonix please let me know. 70miles round trip to work without a car is brutal.
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Old 10-22-2003, 07:52 PM   #2
Lester
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I would not spend alot of time looking at the so called air fuel gauge it is just telling you how much vaccumm your engine is creating at idle, cruz or under power. Generally this gauge is mostly for entertainment.

Can't help you with Phoenix.

But I didn't see where you checked your distributor. GM or not does your distributor have a vacuum advance unit? If so, detach the hose that goes from the carb to the can and gently suck on it either with your mouth or a hand held vacuum pump. If there's resistance then the can should be okay. Now remove the cap and see where the can is attached to the advance plate. Suck on the hose gain you should see the rod move and the advance plate move and when you stop it should immediately go back. Now check the weight plate, gently twist it one way then the other it should move and move the weights. These things can corrode and stick or the plastic slides under the weights can wear out and cause the same type of problem you described, no advance at idle or the advance won't retard.

Good luck.

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Old 10-22-2003, 08:08 PM   #3
Tom
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Thanks lester. I checked everything in the distributor when I changed the cap+rotor. I just installed a crane vaccum can about 3 months ago. I have it hooked to ported vaccum, so I can pull the hose off the carb when its running perfectly and it wont affect the idle one bit. The thing is it still runs fine once Im moving and using a little bit of throttle. Its just at idle or coming off idlethat it has problems. As for the a/f guage, I've been using it for months now it while its far from perfect it still does the job pretty well. When I hit the accelerator pump [whih I made rich on purpose] the gauge will jump up to the rich section for a second before coming back down to below lean [if Im only using a little bit of thorttle] other wise it stays at a fairly constistant ratio. And it is very entertaining at night
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Old 10-22-2003, 10:03 PM   #4
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Quote:
Originally posted by Tom
The thing is it still runs fine once Im moving and using a little bit of throttle. Its just at idle or coming off idlethat it has problems. As for the a/f guage, I've been using it for months now it while its far from perfect it still does the job pretty well. When I hit the accelerator pump [whih I made rich on purpose] the gauge will jump up to the rich section for a second before coming back down to below lean [if Im only using a little bit of thorttle] other wise it stays at a fairly constistant ratio. And it is very entertaining at night
I could be way off base hear as I don’t know all the details but you’re A/F gauge may be telling you your problem if it jumps up when you first hit the throttle it’s telling you your getting the initial hit from the accelerator pump but the fact it drops to sever lean it’s saying your not getting enough duration from the accelerator pump to adequately feed the engine till your main circuits come in to play.
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Old 10-23-2003, 12:53 AM   #5
1976K5CHALET
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Band R automotive....27th ave and mcdowell...right next to az street rods...best of the best...
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Old 10-23-2003, 02:16 AM   #6
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Don't give up on it yet... I spent the last 4 weeks trying to figure mine out The feeling you get from accomplishing it is awesome
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Old 10-23-2003, 11:58 AM   #7
Tom
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Yeah but the feeling of not having enough money left for gas cause I have to buy parts sucks.

It works finally. I didn't do anything else to it. It just started working. Its going in the autotrader this weekend. Im getting a honda.
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-78 c10 short/step: 388cid, M20, 5/5 drop, lots more. Playtoy and first vehicle.
-98 c1500 x-cab: 5.7L, 17" rims, 5/6 drop, flowmaster, helper bags,NBS rear disk brakes.
-02 Suburban 4x4: leveled front
-CBR600F4i, CBR600RR, CBR1000RR, and standup skis
DISCLAIMER: I cant spell for the life of me.
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Old 10-23-2003, 06:17 PM   #8
Low87
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Re: I give up, know of any good mechaincs in phoenix?

Quote:
Originally posted by Tom
If anyone has anything else to check,
Sounds similar to the problems I've been having with water in the gas....
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Old 10-26-2003, 12:23 AM   #9
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lean

I am not that great diagnosing carbs but it sounds like your float was set too low. My friends was driving us nuts like this and it ended up that the float was getting hung up so even when the fuel bowl emptied the float would go down just a little. You probably already check that but I thought i would throw that in
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