 weird high idle with nearly empty tank |
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| dax1969 |
 Mar 3 2023, 07:42 AM
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#1
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Member  Group: Members Posts: 387 Joined: 10-March 14 From: belgium Member No.: 17,103 Region Association: None 
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Hi,
I have a 74 2.0 FI and car idles, after warming up, at a normal 850/900 rpm Yesterday however I had something weird ... In the morning (really cold outside) everything was normal (higher idle on start up, normal idle when warmed up) but on the way back the idle remained at 1200 rpm. I immediately thought vacuumleak. I needed gas as I was running very very low on fuel (warning light came on, never saw it before (IMG:style_emoticons/default/biggrin.gif) ) ... fyi, my tank is shiny and clean as I cleaned and coated the tank last year. After filling up the idle went back to normal... Drove the car again next day, same...all normal. Can low on fuel cause a higher idle ? weird cheers Dax |
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Replies
| Superhawk996 |
Mar 3 2023, 09:23 AM
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#2
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914 Guru Group: Members Posts: 7,025 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch
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A theory:
An empty tank contains much more fuel vapor than a full tank. That is a fact. Wondering if you are somehow pulling vapor directly through a worn out charcoal canister that is saturated and it’s going directly into the intake and causing a higher idle - maybe in conjunction with an AAR that isn’t 100% closed. Mostly wondering out loud - no proof this is it. Alternately you have a minor vacuum leak or AAR didn’t close 100% and the next drive cycle heat loosened thing up and vacuum leak sealed or AAR then closed 100%? Just throwing ideas out there. Would need to troubleshoot deeper to know for sure. |
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Posts in this topic
dax1969 weird high idle with nearly empty tank Mar 3 2023, 07:42 AM
Lockwodo I wouldn't think so, more likely a coincidence... Mar 3 2023, 09:08 AM ChrisFoley There's a little partially crimped vent tube i... Mar 3 2023, 09:49 AM emerygt350 I agree with Chris, it could be a lean condition f... Mar 3 2023, 10:40 AM 76-914 AFAIK that is normal. While I've had my '7... Mar 3 2023, 10:44 AM emerygt350 That is really interesting! Now I have an exc... Mar 3 2023, 02:41 PM Lockwodo ..and a reason to keep a few gallons of gas in the... Mar 3 2023, 03:42 PM wonkipop just shows that a 914 can actually empty its tank ... Mar 3 2023, 05:02 PM ejm Most likely you had icing in the throttle body whi... Mar 3 2023, 05:05 PM
dax1969 Thank you all for the feedback... I'll keep an... Mar 7 2023, 04:54 AM |
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