 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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| r_towle |
Dec 19 2013, 09:40 PM
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#2
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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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Runs good cold, run worse when hot.
Metal expands when heated. Check our valves. |
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| rick 918-S |
Dec 19 2013, 10:28 PM
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#3
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Hey nice rack! -Celette Group: Members Posts: 20,950 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region 
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QUOTE(r_towle @ Dec 19 2013, 09:40 PM)  Runs good cold, run worse when hot. Metal expands when heated. Check our valves. I would agree it is always good to check valves I would think it would be less likely that it would cause a specific RPM range miss or bucking. Fuel delivery or.... (IMG:style_emoticons/default/idea.gif) MAPS is starting to crack. |
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| Jesco Reient |
Dec 20 2013, 08:41 AM
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#4
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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(rick 918-S @ Dec 19 2013, 08:28 PM) QUOTE(r_towle @ Dec 19 2013, 09:40 PM) Runs good cold, run worse when hot. Metal expands when heated. Check our valves. .... (IMG:style_emoticons/default/idea.gif) MAPS is starting to crack. I'm in denial on checking that also but might as well, otherwise I'm just lying to myself. The somewhat progressive nature of this has had me thinking about that diaphragm in the back of my head. |
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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 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 mepstein I had bucking sometimes and a perfect running engi... Jan 23 2014, 09:09 AM Jesco Reient
I had bucking sometimes and a perfect running eng... Jan 23 2014, 09:37 AM r_towle
I had bucking sometimes and a perfect running en... Jan 23 2014, 01:37 PM Jesco Reient OK, todays test drive revealed a nice smooth pull ... Jan 23 2014, 07:55 PM |
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