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> Choke under load
914itis
post Mar 23 2012, 03:47 PM
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Taking the car out for the first time. couldn't make it to 2nd gear as it lost acceleration under load. the car revs fine, but lost acceleration under load at about 2500-3000 rpm. I can feel the lost even when pulling in and out of the driveway.

I reconfirmed timing,
Dwell is 47.5
fuel pressure is at 29lbs

2.0 djet
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luskesq
post Mar 23 2012, 05:14 PM
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I'd double check your ignition (sparkplug) wires to make sure you haven't got them mixed, as well as timing.

Good luck, that kind of thing can be frustrating.

Keith
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914itis
post Mar 23 2012, 07:50 PM
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QUOTE(luskesq @ Mar 23 2012, 07:14 PM) *

I'd double check your ignition (sparkplug) wires to make sure you haven't got them mixed, as well as timing.

Good luck, that kind of thing can be frustrating.

Keith

timing is right
plug wires sequence is correct


planning on changing point and condenser, test mps and injectors.
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914itis
post Mar 23 2012, 10:10 PM
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Ran a pressure test on mps . I put 15 lbs of pressure and timed it for 5 minutes I lost about 2 pounds. Is that normai?
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Prospectfarms
post Mar 23 2012, 11:53 PM
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As I understand how they work, loosing two pounds of vacuum after five minutes shouldn't affect MPS operation. The one I'm using looses five in two minutes. Engine runs fine.
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TheCabinetmaker
post Mar 24 2012, 05:24 AM
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2 lbs in 5 minutes is acceptable leakage. Have you done a valve adjustment?
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walterolin
post Mar 24 2012, 05:59 AM
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Fuel filter? Crimp in an incoming fuel line?
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wingnut86
post Mar 24 2012, 12:57 PM
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I dumped my 1st girlfriend for the very reason you named your post (IMG:style_emoticons/default/beer.gif)

Stlll sounds like gas, fuel filter, dirty tank...
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underthetire
post Mar 24 2012, 01:04 PM
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You set timing, but did you check it? Is it actually advancing?
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914itis
post Mar 24 2012, 03:24 PM
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 Checked valves and they were a bit off . I adjusted them, checked the injectors they squirt nicely . Changed the points and re- timed, verified dwell, found one linked fuel line ( not that much just a bit) changed fuel filter, no change . I am about to adjust my tps and do a compression tst 
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914itis
post Mar 24 2012, 08:07 PM
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I adjusted my tps to .003 ohms, I checked compression 160 on cyl 4 and 152 on 1, 2 and 3.

It idles nicely even revs nice if not driven. I still have the same issue. It is misfiring under load .

My question is now, what are the common cause of misfiring on duet
What am I missing?

The only thing I can think of is that I am not doing the timing right.
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rgalla9146
post Mar 24 2012, 08:39 PM
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QUOTE(ppetion @ Mar 23 2012, 01:47 PM) *

Taking the car out for the first time. couldn't make it to 2nd gear as it lost acceleration under load. the car revs fine, but lost acceleration under load at about 2500-3000 rpm. I can feel the lost even when pulling in and out of the driveway.

I reconfirmed timing,
Dwell is 47.5
fuel pressure is at 29lbs

2.0 djet

Paul
Ray just had a problem that was similar. He say's it's a CHT.
Stumbles on acceleration.
It's an easy thing to check or change out if you have a spare.
Check it with an Ohm meter. Value changes with temp.
Bowlsby has the range of specs.
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914itis
post Mar 25 2012, 09:00 PM
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After a long day with Scott, we went over everything in the the car, cht, vacuums, and timing, we had no results. As he was about leave we decided to test the vacuum advance on the dizzy, and noticed that it was defective no movement when air is sucked out of the ports. He left and I went on to install a dizzy that he came with. The points were shot, I replaced them, lubed it and that solved the issue.

The car is running great with good power.

ThanKs to all for all your help. It has been a great learning experience. I now know how to test, diagnosed and adjust just about everything on a diet. (IMG:style_emoticons/default/piratenanner.gif)

I can now move on the the next task. (interior)
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Prospectfarms
post Mar 25 2012, 09:14 PM
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(IMG:style_emoticons/default/smilie_pokal.gif)
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TheCabinetmaker
post Mar 26 2012, 12:25 PM
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(IMG:style_emoticons/default/piratenanner.gif) (IMG:style_emoticons/default/beerchug.gif) Now you can (IMG:style_emoticons/default/driving.gif)
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