914 idle issue, i've search but found nothing |
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914 idle issue, i've search but found nothing |
justdrive914 |
Aug 25 2008, 04:23 PM
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#1
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Member Group: Members Posts: 88 Joined: 31-July 08 From: Asheville, NC Member No.: 9,374 Region Association: South East States |
my 914 1.7L is all oe and I've done a lot of work to it. i replaced a lot of parts and now i cant get my idle to 975 or so it seems to stay at 1800 whats the deal anyone know? i have adjusted and adjusted, i cant get it!???
Thanks andrew |
warrenoliver |
Aug 25 2008, 04:32 PM
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#2
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Member Group: Members Posts: 363 Joined: 11-November 06 From: McFarland, Wisconsin Member No.: 7,199 Region Association: Upper MidWest |
Andrew,
I'm not too much help, but I think you can get a lot of info if you search "vacuum leak". Good luck. Warrenoliver |
SirAndy |
Aug 25 2008, 05:11 PM
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#3
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Resident German Group: Admin Posts: 41,679 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
"vacuum leak" (IMG:style_emoticons/default/agree.gif) Sounds like you got a air leak somewhere on the intake side ... (IMG:style_emoticons/default/bye1.gif) Andy |
r_towle |
Aug 25 2008, 05:37 PM
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#4
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Custom Member Group: Members Posts: 24,588 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
also
Rich Attached image(s) |
justdrive914 |
Aug 25 2008, 05:56 PM
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#5
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Member Group: Members Posts: 88 Joined: 31-July 08 From: Asheville, NC Member No.: 9,374 Region Association: South East States |
also Rich thanks man, i do think its a vacuum (IMG:style_emoticons/default/wacko.gif) leak! is there an easier way to find the bad boy or is it check till i find it? |
r_towle |
Aug 25 2008, 06:07 PM
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#6
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Custom Member Group: Members Posts: 24,588 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
one Djet.
Unplug every vacuum line and plug it. Only leave the MPS plugged into the plenum. You dont need any other lines to run. Common leaks are at the AAR valve, and the rubber "Y" fitting for both that and the decel valve. Add them back one at a time till you find the issue. Sometimes the AAR valve gets stuck open and that creates a pretty large leak. Rich |
Joe Ricard |
Aug 25 2008, 10:16 PM
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#7
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
At your own risk you can use something like ether SPARINGLY around all the suspect places metioned above.
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tracks914 |
Aug 26 2008, 06:28 PM
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#8
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Canadian Member Group: Benefactors Posts: 2,083 Joined: 15-January 03 From: Timmins, Ontario, Canada Member No.: 153 Region Association: None |
I've had the same issue for 4 years. It idles about 1500 (cold) until it warms up,(HOT) then it drops to about 700. BTW it seems to lose about 25% of it's power/torque when it gets that hot. I think the cold start valve helps with the power.
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Rand |
Aug 26 2008, 06:46 PM
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#9
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Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
Cold start valve just injects extra fuel IF the temps are VERY cold (like near freezing).
Things that can cause high idle on DJet: 1. Vacuum leak below throttle's butterfly. 2. Throttle butterfly not closing squarely. 3. Overly advanced timing. Sometimes tracing the vacuum leak can be a pain, but it most certainly can be a simple and methodical process because there are only so many potential sources between the butterfly and the heads, so follow the path.... -Injector seals (2 per injector) -Phenolic block between heads and intake runners -Rubber boots between intake runners and plenum -Crack in plenum (usually around vertical reinforcement tubes) -Gasket between plenum and throttle body -Excess wear around butterfly pivots -Air bypass / idle adjust screw in throttle body -Any vacuum tap on plenum or throttle body below butterfly. (Some of those taps have to be traced upstream to parts that can cause the problem, like the AAR. But on Djet, you can just pull the hose and plug the hole like Rich said to help troubleshoot most of those.) |
r_towle |
Aug 26 2008, 07:30 PM
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#10
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Custom Member Group: Members Posts: 24,588 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
I've had the same issue for 4 years. It idles about 1500 (cold) until it warms up,(HOT) then it drops to about 700. BTW it seems to lose about 25% of it's power/torque when it gets that hot. I think the cold start valve helps with the power. Your AAR is what makes it idle higher when cold and then settle to 700 when hot. 700 is to low btw. It supposed to do that..its like a choke. The AAR adds more air when cold and this makes the motor run faster... Your AAR may be leaking and not sealing up when closed.. Rich |
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