 My 914 still runs rough until warmed up HELP? |
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| Kalva |
 Sep 24 2010, 01:05 PM
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#1
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Newbie  Group: Members Posts: 38 Joined: 25-June 10 From: Long Island NY Member No.: 11,882 Region Association: North East States  |
I've had my 71' teener since July and have done a complete tune up, points, dwell timing, valve addjusted etc. When the car is first started up she runs rough for 5-10 mins then runs fine. If I try to drive before the 5-10 min warm up she stutters and as I depress the gas chokes and goes nowhere slow... Idle is set around 1000 and will search up and down between 900-1300. Ive checked for leaks in all the vac lines, checked fuel injector seals. Read threw 700 tech tips & Haynes books.
If any one has any idea please let me know as I should be able to start the car a go for a drive or is this normal. Thanks... |
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| rwilner |
Sep 24 2010, 08:27 PM
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#2
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No Ghosts in the Machine Group: Members Posts: 953 Joined: 30-March 10 From: Boston, MA Member No.: 11,530 Region Association: North East States |
QUOTE(Kalva @ Sep 24 2010, 03:05 PM)  I've had my 71' teener since July and have done a complete tune up, points, dwell timing, valve addjusted etc. When the car is first started up she runs rough for 5-10 mins then runs fine. If I try to drive before the 5-10 min warm up she stutters and as I depress the gas chokes and goes nowhere slow... Idle is set around 1000 and will search up and down between 900-1300. Ive checked for leaks in all the vac lines, checked fuel injector seals. Read threw 700 tech tips & Haynes books. If any one has any idea please let me know as I should be able to start the car a go for a drive or is this normal. Thanks... I'm pretty sure you have L-Jet on a 71, but here's PBander's amazing D-jet site. Might at least give you some ideas. |
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| hot_shoe914 |
Sep 24 2010, 10:16 PM
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#3
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on ramp passer Group: Members Posts: 3,802 Joined: 20-November 07 From: Earle, Ar. Member No.: 8,354 Region Association: None |
QUOTE(Kalva @ Sep 24 2010, 02:05 PM) I've had my 71' teener since July and have done a complete tune up, points, dwell timing, valve addjusted etc. When the car is first started up she runs rough for 5-10 mins then runs fine. If I try to drive before the 5-10 min warm up she stutters and as I depress the gas chokes and goes nowhere slow... Idle is set around 1000 and will search up and down between 900-1300. Ive checked for leaks in all the vac lines, checked fuel injector seals. Read threw 700 tech tips & Haynes books. If any one has any idea please let me know as I should be able to start the car a go for a drive or is this normal. Thanks... Bring it down to the MUSR11 in October and I am sure one of the many teener techs will solve it for you. (IMG:style_emoticons/default/poke.gif) |
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| swl |
Sep 25 2010, 07:25 AM
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#4
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Senior Member Group: Members Posts: 1,409 Joined: 7-August 05 From: Kingston,On,Canada Member No.: 4,550 Region Association: Canada |
71= 1.7L =DJet
LJet was used on the 1.8L in 74 and later The hunting up and down is the interesting symptom. I have no idea what would cause that. Rough operation during warm up including off idle makes me think CHT. Have you measured the resitance cold and hot? The link Rich gave you will tell you what the expected value are. |
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| Bleyseng |
Sep 25 2010, 07:30 AM
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#5
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Aircooled Baby! Group: Members Posts: 13,034 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest |
What MPS are you running along with what ECU?
The later 037 ECU have a knob to adjust the idle mix. Makes it easier to clean up the rough idle. |
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| Kalva |
Sep 25 2010, 04:51 PM
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#6
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Newbie Group: Members Posts: 38 Joined: 25-June 10 From: Long Island NY Member No.: 11,882 Region Association: North East States |
Yes I have a non-adjustable D-Jet. Rwilner thanks for the link I'm working my way thru it now. Swl how would I check the CHT resistance?
Thanks guy for the info... |
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| swl |
Sep 26 2010, 06:18 AM
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#7
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Senior Member Group: Members Posts: 1,409 Joined: 7-August 05 From: Kingston,On,Canada Member No.: 4,550 Region Association: Canada |
The CHT is on the head, passenger side, rear cylinder. You can't actually see the sensor itself but the single lead comes out of the tin back there. Easy to spot. There should be a connector to the wiring harness about an inch and half down the lead. Just break it there and measure to ground. Measure cold, reconnect, warm up, measure again.
That's the quick and dirty. In my opinion the best way is to remove the harness at the ecu and take all your measurements there. That way you take into account any problems with the harness or connectors. Brad Anders site has the entire checklist of what you should read at the different terminals. If you go through the checklist you can pretty much eliminate any electrical/sensor fault. |
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