 Carbs, Sick of dealing with the D-Jet |
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| BMXerror |
 Jun 25 2006, 05:19 PM
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#1
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Senior Member  Group: Members Posts: 1,705 Joined: 8-April 06 From: Hesperia Ca Member No.: 5,842  |
Well, my car has been almost ready to run for about a month and a half now. It just runs WAY too fat and I can't figure out why. I've replaced the fuel pump, cleaned the injectors and tested them, adjusted the fuel pressure, Blah blah blah. It's still runs way too rich (when it's not too flooded to run at all, that is), and in the process of my diagnostic, all my wires are breaking right at those stupid little plastic connectors, and they're not really solderable. The only thing really left is to replace the whole loom and computer, but I don't really want to get into that.
My question: What is a good carb setup for a 1.7? The simpler the better. As an alterative, since I want to go to a bigger motor and weber 44s later anyways, would it work to put the 44s on with smaller venturis? Any help just to get this thing on the road would be appreciated, because I'm rather frustrated at this point. 107 posts, four months, $4000, and I haven't even driven a 914 yet. (IMG:style_emoticons/default/ar15.gif) Mark D. |
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| So.Cal.914 |
Jun 25 2006, 05:26 PM
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#2
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"...And it has a front trunk too." Group: Members Posts: 6,588 Joined: 15-February 04 From: Low Desert, CA./ Hills of N.J. Member No.: 1,658 Region Association: None |
I don't see any reason why you could not jet the 44's down, changing the venturies
should not be nesessary. |
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| Mark Henry |
Jun 25 2006, 05:26 PM
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#3
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Keep the FI.....put a mega-squirt on it for about the same price as carbs or an SDS for a bit more.
Check out http://sdsefi.com/ and http://www.megasquirt.info SDS is a commercial system with lots of tech support and is pretty simple to program and the mega-squirt is a DIY kit, a lot more work but cheap. Both systems will need a wide band a/f (air/fuel) meter. Most of it will hook up to your existing FI and you can build a big engine someday. |
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| Thack |
Jun 25 2006, 05:36 PM
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#4
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Member Group: Members Posts: 283 Joined: 1-June 05 From: Houston, Tx Member No.: 4,182 |
For a stock motor 36s seem like a better choice. You could probably slim down a pair of 40s.
http://www.cbperformance.com/catalog.asp?ProductID=493 |
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| BMartin914 |
Jun 25 2006, 05:37 PM
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#5
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||| Group: Members Posts: 1,408 Joined: 30-May 04 From: Oregon Member No.: 2,128 Region Association: Pacific Northwest |
Why do you think you need a new ECU? They rarely fail.
Chances are, all of the small breaks in the wiring harness are contributing to / causing your problem. A new harness from Bowlsby would be cheaper and easier than a changeover to carbs. |
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| SirAndy |
Jun 25 2006, 05:38 PM
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#6
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Resident German Group: Admin Posts: 42,257 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
QUOTE(So.Cal.914 @ Jun 25 2006, 04:26 PM)  I don't see any reason why you could not jet the 44's down, changing the venturies should not be nesessary. without changing the venturis to a smaller size, you'll have a HUGE flatspot off idle ... just get a single progressive carb for now, people are throwing them away, you should be able to pick one up for just the shipping costs ... (IMG:style_emoticons/default/popcorn[1].gif) Andy |
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| Dr Evil |
Jun 25 2006, 05:39 PM
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#7
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Send me your transmission! Group: Members Posts: 23,041 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region 
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CHT? MAP?
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| Mark Henry |
Jun 25 2006, 05:50 PM
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#8
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
QUOTE(SirAndy @ Jun 25 2006, 07:38 PM) just get a single progressive carb for now, people are throwing them away, you should be able to pick one up for just the shipping costs ... (IMG:style_emoticons/default/popcorn[1].gif) Andy I hope (I know) Andy's kidding (IMG:style_emoticons/default/alfred.gif) (IMG:style_emoticons/default/chair.gif) I'd rather just take a nice big (IMG:style_emoticons/default/stromberg.gif) on top of my engine....It would probably run better. |
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| Dr Evil |
Jun 25 2006, 05:53 PM
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#9
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Send me your transmission! Group: Members Posts: 23,041 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region
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DD once recommended a monkey with a squirt bottle as an alternative to a single barrel that Red-beard was selling (IMG:style_emoticons/default/dry.gif)
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| lapuwali |
Jun 25 2006, 06:12 PM
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#10
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743  |
I agree with Mark H. MS or SDS will be tunable, so you can run with the engine you have now, and tune it up later for the bigger engine. You'll need to do more wiring, though, and if you'd rather not do that, then carbs would be a better choice.
Of course, then you'll start complaining about all the things like go wrong with carbs, like dirt in the idle jets, stuck floats, noise, etc. As for your D-Jet problems, wiring doesn't generally cause rich mixtures. I'd suspect your intake temp sensor, your MPS, and your CHT more or less in that order. Do Brad Ander's resistance tests on the temp sensors, using the ECU end of the wires, not the sensor end (this eliminates the wiring if it's good). Look up the ECU and MPS part numbers and makesure you have the right ones for your engine (and each other). |
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| BMXerror |
Jun 25 2006, 06:17 PM
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#11
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Senior Member Group: Members Posts: 1,705 Joined: 8-April 06 From: Hesperia Ca Member No.: 5,842 |
QUOTE(Dr Evil @ Jun 25 2006, 04:53 PM) DD once recommended a monkey with a squirt bottle as an alternative to a single barrel that Red-beard was selling (IMG:style_emoticons/default/dry.gif) HAHAHAHAHAH..... That's about how I'm feeling with the D-jet at this point. The reason I suspected that it could be the ECU is that's about the only thing left that I haven't tested. However, when I wrote that I forgot about the Manifold Vacuum sensor, which is probably more likely to fail. And YES, the small wire breaks are definately contributing to my problem. Since I origionally posted about an hour ago, the thing has also decided to run on only two cylinders, which I attribute to a broken wire that I can't fix RIGHT that keeps coming off. If I am to keep the stock injection, I need to replace those stupid plastic connectors. They break and there's really no way to resolder them well. As for my mixture problem, I'm guessing I should check the vacuum line to the airflow meter, and the airflow meter itself(just thinking outloud). In the meantime, I'll think of your alternative solutions. Anyone else have an idea of what my problem might be? thanks Mark D. |
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| Air_Cooled_Nut |
Jun 25 2006, 06:33 PM
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#12
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914 Ronin - 914 owner who lost his 914club.com Group: Members Posts: 1,748 Joined: 19-April 03 From: Beaverton, Oregon Member No.: 584 Region Association: None |
Replacing parts that don't need to be replaced is wasting money. You need to trouble-shoot your issues and make fixes from there.
Can you get a hold of a D-Jet FI tester? That can quickly help find most problems. VOM will, also, but not as quickly nor easily. Your FI computer needs to be the correct unit, you just can't throw in another unit and expect it to work, they have to be the same model/generation and match the other FI parts on your engine. And the brains rarely fail. Make sure you have taken care of all vacuum leaks. Replace ALL of the vacuum hoses. If you don't want to replace the intake runner hoses that connect the intake runners to the intake plenum then you can put a hose clamp at each end as a bandaid until you get proper replacements. But the rest of the hoses should be replaced with new units. I did my engine with the stock looking braided hoses from my FLAPS and it wasn't expensive at all. See Dave Darling's hose FAQ for estimating sizes and lengths. See my web site for more help: http://www.icbm.org/erkson/personal/Porsch...nuals/index.htm |
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| BMXerror |
Jun 25 2006, 07:05 PM
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#13
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Senior Member Group: Members Posts: 1,705 Joined: 8-April 06 From: Hesperia Ca Member No.: 5,842 |
Well, that's part of the problem. I AM trouble shooting and trying to track the problem, but I've been chasing three different problems for some time. I had an intermitent power connection to the fuel pump, and a malfunctioning fuel pump that were confusing my diagnosis. I've since fixed those two problems. Now I think I'm only chasing one problem, but I'm still in kinda in over my head. I picked a hell of a first project car. Anyways, I'm not just arbitrarily replacing parts. The only thing I was talking about replacing was the ENTIRE system for simplicity's sake, but as Lapuwali correctly pointed out, I'll then be having carb problems, which I also don't want. I think I'm gonna try to fix all the electrical connections first, and then check and make sure all the parts are compatable. Then I'll start chasing again. Thanks guys.
Mark D. |
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| Allan |
Jun 25 2006, 07:10 PM
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#14
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Teenerless Weenie Group: Members Posts: 8,373 Joined: 5-July 04 From: Western Mesopotamia Member No.: 2,304 Region Association: Southern California |
FI is way cool if it's set-up properly.
Carbs are WAY cool if set up properly. Like reostats? = FI. Like light switches? = Carbs. From what I've seen (and that's limited use of both) FI is great if you want the instant start and go to work kind of thing. Carbs are great if you like the instant on, instant off and roar in your ears kind of thing. Your choice..... |
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| Chris Pincetich |
Jun 25 2006, 07:13 PM
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#15
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B-) Group: Members Posts: 2,082 Joined: 3-October 05 From: Point Reyes Station, CA Member No.: 4,907 Region Association: Northern California |
(IMG:style_emoticons/default/happy11.gif) I know wrenching is fun, BUT another option for 1-2K is to keep an eye out in the classifieds for "complete running engine for sale - come listen before I pull it out for my swap". (IMG:style_emoticons/default/happy11.gif) (IMG:style_emoticons/default/happy11.gif) (IMG:style_emoticons/default/happy11.gif)
(IMG:style_emoticons/default/beerchug.gif) |
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| So.Cal.914 |
Jun 25 2006, 07:15 PM
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#16
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"...And it has a front trunk too." Group: Members Posts: 6,588 Joined: 15-February 04 From: Low Desert, CA./ Hills of N.J. Member No.: 1,658 Region Association: None |
Iam running duel webers, I have had to clean a few jets in my time. Never had a
float goof up or a needle and seat. I throw a rebuild kit into them every three years or so, other than that no problems. As far as carb noise, I like to hear the monster breathe. The carbs have been on there sense 1982. |
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| BMXerror |
Jun 25 2006, 07:46 PM
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#17
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Senior Member Group: Members Posts: 1,705 Joined: 8-April 06 From: Hesperia Ca Member No.: 5,842 |
Yeah, for now I'm gonna try to fix the FI because that's what's in there. Like I say, right now I just want to get it running so I can drive it. I'm kinda short on money right now just from getting the rest of the car ready anyway. For later I may consider some sort of aftermarket computer controlled injection system(and ignition for that matter). BTW, who on this forum cares about noise? (IMG:style_emoticons/default/biggrin.gif)
Mark D. |
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| Trekkor |
Jun 25 2006, 07:53 PM
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#18
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
My Webers make me happy.
KT |
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| Aaron Cox |
Jun 25 2006, 07:57 PM
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#19
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Professional Lawn Dart Group: Retired Admin Posts: 24,542 Joined: 1-February 03 From: Corona, CA Member No.: 219 Region Association: Southern California |
QUOTE(trekkor @ Jun 25 2006, 06:53 PM) My Webers make me happy. KT clogged idles make me sad (IMG:style_emoticons/default/sad.gif) but WOT weber roar makes me happy (IMG:style_emoticons/default/smile.gif) flat spot on transition makes me sad (IMG:style_emoticons/default/sad.gif) Buying jets and tinkering with webers makes me happy (IMG:style_emoticons/default/smile.gif) get it right and it is maintenance free LOL |
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| Trekkor |
Jun 25 2006, 08:06 PM
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#20
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
Yep, i clean my idles every now and then...that's it.
KT |
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