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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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| rick 918-S |
Dec 19 2013, 03:44 PM
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#2
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Hey nice rack! -Celette ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 21,220 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region
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From the sounds of your last post about going through the entire F.I. and refurbishing the vacuum hoses and electrical connections I would start to suspect fuel delivery. I wonder if the fuel pump is weak. Describe the bucking. is it a miss or a stall?
Miss could be from the spark plug wire interfering with the MAPS. Someplace around here there is some info about keeping the plug wire away from the MAPS as it will cause issues. Stall could be from weak pump. |
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
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
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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