 Starts out smooth, then what the buck? |
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| Jesco Reient |
 Dec 18 2013, 06:24 PM
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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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| gunny |
Dec 19 2013, 08:29 PM
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Member Group: Members Posts: 205 Joined: 17-October 12 From: Madison Al Member No.: 15,051 Region Association: South East States |
I had the same type of issue and after about a year of working on it i installed a wideband A/F meter. Found out I was running very lean and it leaned out so much at about 3700 rpms that it would loose power and buck. I had to adjust my MPS to get it running great with no issues now.
Try unplugging the temp sensor #2 on top of the intake plenum. It will richen it up some. If that helps then you may need some MPS tuning. |
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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 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 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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