 Starts out smooth, then what the buck? |
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| Jesco Reient |
 Dec 18 2013, 06:24 PM
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#1
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Member  Group: Members Posts: 135 Joined: 18-July 12 From: Western Washington Member No.: 14,690 Region Association: Pacific Northwest  |
When I first start the car cold for the day. (2056, D-jet, Raby 9590 cam, timing 27 advance @3500) The car has no cold start valve but has not seemed to care. First start it runs smoothly pulls away from the house shifting @ 3500 it acts nicely. After warming up for awhile as the motor reaches 3200 to 3600 it bucks severely then above 3600 it smooths out a bit. Then as it gets warmer the bucking moves down the RPM range to 2600 to 2800 RPM becoming not very drivable. any ideas out there? (IMG:style_emoticons/default/confused24.gif)
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| mepstein |
Jan 23 2014, 09:09 AM
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#2
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914-6 GT in waiting Group: Members Posts: 20,532 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region 
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I had bucking sometimes and a perfect running engine other times. I changed the coil on mine and the bucking went away. I had tried all the other suggestions. Just a thought.
Once you get it fixed you will be glad you did not switch to carbs. |
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| Jesco Reient |
Jan 23 2014, 09:37 AM
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#3
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Member Group: Members Posts: 135 Joined: 18-July 12 From: Western Washington Member No.: 14,690 Region Association: Pacific Northwest |
QUOTE(mepstein @ Jan 23 2014, 07:09 AM)  I had bucking sometimes and a perfect running engine other times. I changed the coil on mine and the bucking went away. I had tried all the other suggestions. Just a thought. Once you get it fixed you will be glad you did not switch to carbs. The coil has been nagging at my mind since that is the only part NOT replaced during the rebuild, I just have not gone there yet. The TPS is set again by the ohm-meter method, and the resistance readings on the MPS were right on the numbers. |
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| r_towle |
Jan 23 2014, 01:37 PM
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#4
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Custom Member Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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QUOTE(Jesco Reient @ Jan 23 2014, 10:37 AM) QUOTE(mepstein @ Jan 23 2014, 07:09 AM) I had bucking sometimes and a perfect running engine other times. I changed the coil on mine and the bucking went away. I had tried all the other suggestions. Just a thought. Once you get it fixed you will be glad you did not switch to carbs. The coil has been nagging at my mind since that is the only part NOT replaced during the rebuild, I just have not gone there yet. The TPS is set again by the ohm-meter method, and the resistance readings on the MPS were right on the numbers. Have you removed and cleaned the advance plates inside the distributor? |
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Posts in this topic
Jesco Reient Starts out smooth, then what the buck? Dec 18 2013, 06:24 PM
boxsterfan
When I first start the car cold for the day. (205... Dec 18 2013, 06:32 PM Jesco Reient
Could be TPS worn, trigger points on dizzy or fu... Dec 18 2013, 07:57 PM boxsterfan Also, how about your fuel filter? Clogged?
Or a ... Dec 19 2013, 10:57 AM
Jesco Reient
Also, how about your fuel filter? Clogged?
Or a... Dec 19 2013, 11:46 PM r_towle
r_towle
"What is your valve train setup?
Al... Dec 20 2013, 10:48 AM r_towle What is your valve train setup?
Aluminum or chromo... Dec 19 2013, 12:13 PM rick 918-S From the sounds of your last post about going thro... Dec 19 2013, 03:44 PM gothspeed The above is good advice ..... the only thing I... Dec 19 2013, 08:18 PM rmital
The above is good advice ..... the only thing I... Dec 19 2013, 08:36 PM Mike Bellis What everyone is eluding to here is you have a lea... Dec 19 2013, 08:29 PM gunny I had the same type of issue and after about a yea... Dec 19 2013, 08:29 PM 914GT Maybe try retarding the timing a few degrees and s... Dec 19 2013, 09:16 PM r_towle Runs good cold, run worse when hot.
Metal expands ... Dec 19 2013, 09:40 PM rick 918-S
Runs good cold, run worse when hot.
Metal expands... Dec 19 2013, 10:28 PM Jesco Reient
Runs good cold, run worse when hot.
Metal expand... Dec 20 2013, 08:41 AM rick 918-S You may want to re-run a test on your MAPS too jus... Dec 20 2013, 06:42 AM gunny http://www.aemelectronics.com/wideband-air...-fuel... Dec 20 2013, 07:15 AM boxsterfan http://members.rennlist.com/pbanders/DJetP...tm#tr... Dec 20 2013, 10:44 AM rhodyguy have you calibrated the tps using a proper plug, j... Dec 20 2013, 11:22 AM Jesco Reient
have you calibrated the tps using a proper plug, ... Jan 22 2014, 06:59 PM rmital
............As suggested I tried running the head... Jan 23 2014, 11:28 AM Jesco Reient
............As suggested I tried running the hea... Jan 23 2014, 02:44 PM gunny If the issue is RPM sensitive and not throttle pos... Dec 20 2013, 11:40 AM Jesco Reient
If the issue is RPM sensitive and not throttle po... Dec 20 2013, 04:23 PM Jesco Reient Today has been a research and reading day, letting... Dec 20 2013, 04:22 PM Java2570 I've seen a lot of other threads with folks us... Jan 23 2014, 07:54 AM Jesco Reient OK, todays test drive revealed a nice smooth pull ... Jan 23 2014, 07:55 PM |
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