1.7L running rough in the mid RPMs, Potential Causes of rough running (MIDS) |
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1.7L running rough in the mid RPMs, Potential Causes of rough running (MIDS) |
scwade |
Oct 12 2003, 08:43 PM
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#1
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Newbie Group: Members Posts: 10 Joined: 31-August 03 From: santa clara, ca Member No.: 1,091 |
I have a 1971 1.7L (with big bore kit) running FI. I'm having some odd behavior between 4,000-4,300 RPM. It runs rough at that RPM regardless of gears/speed.
I've checked timing at 3,500 (fine). I've swapped spark plugs (bosh) // got rid of some pre-detination ping, but still have the roughness (cutting out) I've put in 91 octane (best I can get here in CA) Still happens. PS - it idles rough as well. When I remove the "retardation" line it idles fine. I've not tried to run it full boar with no retardation though. Any ideas? Scott |
scwade |
Oct 25 2003, 10:08 PM
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#2
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Newbie Group: Members Posts: 10 Joined: 31-August 03 From: santa clara, ca Member No.: 1,091 |
Ok gents...The rebuilt Dizzy advice was great. Part came very quick, Easily removed and installed the new one. I ended up getting a cap and rotor and cables as well (those were local from Kragen, so wasn't able to get all the good German stuff). The new rotor was no good (couldn't get stable dwell readings) so I used the old rotor and set the dwell to 45 (best I could get to).
I set the timing by the book (27deg at 3500 rpm no retard, or advance air). It runs like its not timed now (alot of work with no HP). Fuel pressure is at 29.5 (I tried it at 30.5 as well). The car runs sluggish now (although seems not to sputter much). I'm sure I've misadjusted something (Dwell at 45. timing at 27 (red), fuel pump at 29.5). I must have some other bad component or I'm just daft. I guess I'll sleep on it. Any other ideas? Cheers, Scott |
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