Weird ignition problems, I think... |
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Weird ignition problems, I think... |
TonyAKAVW |
Jul 13 2005, 03:19 PM
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#1
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That's my ride. Group: Members Posts: 2,151 Joined: 17-January 03 From: Redondo Beach, CA Member No.: 166 Region Association: None |
I converted to a point-less ignition module some months ago, and up until recently had no problems with the engine. A month ago or so I was driving and had the car heated up pretty well, when it started to have problems at low RPMs. The tack started going nuts, and unless I had the engine at high rpms it would stall out. This only happened when the engine got hot. My daily commute is nor more than 10 minutes each way so it wasn't really much of an issue.
So I took off the cap and things looked funny inside. The part that the rotor rubs against at the middle of te cap was worn pretty good for being only a few months old. It also looked like the rotor was striking the contacts at their tops. My thought was that the little disk with magnets for electronic ignition module was causing the rotor to stick up too high and when the car got hot, the shaft of the distributor got a little longer and passed the threshold of working. so I sanded down some of the base of the rotor and put it back in. It seemed to help a bit. The next problem I fixed was a leaking fuel line which I caught very quickly. Ignition was still not working great however until I pulled out the rotor and wiggled it back in a little better. Today on the way to the dentist (a bit farther than the car usually goes) another weird thing started happening. If I didn't hold the throttle open a bit the engine would idle on 1 or 2 cylinders for a few beats and then die. Occacional backfires too. So I'm still thinking its an ignition problem... The tach would drop very quickly to 0, unless I had my foot on the pedal. Does this sound like a TPS problem maybe???? The engine runs very well except when it is allowed to die. Its not missing, etc. Just struck me as odd that it would behave the way it is. My current plan is to get a new ignition module, maybe a pertronix, and install it to see if that helps it. Any other suggestions? -Tony |
bondo |
Jul 13 2005, 03:30 PM
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#2
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
Replace the cap and rotor, once they get messed up they stay that way.
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mightyohm |
Jul 13 2005, 03:34 PM
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#3
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Advanced Member Group: Benefactors Posts: 2,277 Joined: 16-January 03 From: Seattle, WA Member No.: 162 Region Association: Pacific Northwest |
Tony, did you fix the exposed wire on the points module?
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phantom914 |
Jul 13 2005, 03:34 PM
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#4
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non-914-owner non-club member Group: Benefactors Posts: 1,013 Joined: 24-February 04 From: Covina,CA(North ofWest Covina) Member No.: 1,708 |
Darn! I was hoping that by continuing to use them, they would fix themselves. Andrew |
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Aaron Cox |
Jul 13 2005, 03:38 PM
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#5
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
You guys are all Electrical Engineers..... (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif)
looks like you need an ME to solve this one (IMG:http://www.914world.com/bbs2/html/emoticons/ph34r.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/lol2.gif) |
bondo |
Jul 13 2005, 03:40 PM
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#6
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
What did you just call me??!?! I'm a.. um.. a... hmm. |
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phantom914 |
Jul 13 2005, 03:42 PM
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#7
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non-914-owner non-club member Group: Benefactors Posts: 1,013 Joined: 24-February 04 From: Covina,CA(North ofWest Covina) Member No.: 1,708 |
Please don't insult Bondo! (IMG:http://www.914world.com/bbs2/html/emoticons/mad.gif) Andrew |
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Aaron Cox |
Jul 13 2005, 03:43 PM
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#8
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
his post snuck in when i was typing......
royce is an architect right? he can make it work on paper then... (IMG:http://www.914world.com/bbs2/html/emoticons/w00t.gif) |
phantom914 |
Jul 13 2005, 03:46 PM
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#9
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non-914-owner non-club member Group: Benefactors Posts: 1,013 Joined: 24-February 04 From: Covina,CA(North ofWest Covina) Member No.: 1,708 |
He never got a round tuit. He was too busy trying to get Euro lenses for me and bondo. Andrew |
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bondo |
Jul 13 2005, 03:48 PM
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#10
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
I have a degree in architecture, but I don't think I'd like being one that much. Besides, I can't find an architecture job here. For the time being I am working half time at Cal Poly as a technician, and fill in working at Go Westy (a vanagon place). I don't know what I want to be when I grow up. (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif) |
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TonyAKAVW |
Jul 13 2005, 03:53 PM
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#11
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That's my ride. Group: Members Posts: 2,151 Joined: 17-January 03 From: Redondo Beach, CA Member No.: 166 Region Association: None |
yeah! I was trying to get euro lenses for you guys from that dude. That dude is a weird guy. He has all this stuff he wanted to sell, took FOREVER to get me a list of stuff, and then when I told him what we wanted by email and by voice mail he never got back to me. Very weird. But at least I managed to get a good roller out of him for a good price.
ya ya ya. It is funny though that Mr. Architect has the only useful advice. (IMG:http://www.914world.com/bbs2/html/emoticons/idea.gif) I guess us Lectrucul Engunears are just good for nuthins. Or "sparkys" as the MEs call us here. -Tony |
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fadler15222 |
Jul 13 2005, 04:01 PM
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#12
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Newbie Group: Members Posts: 7 Joined: 13-May 05 From: San Diego Member No.: 4,071 |
Back to answers...........whether related or not, I have exactly the same thing and it drove me crazy. I broke down and took it to a local guru. First, the replacement of cap etc., then the replacement of the MPS. I got an old one from a type 4 VW and had it calibrated by Jeff Bowlsby in San Jose. The problem was that I forgot I had a big bore kit and hydraulic valves in the car. It took some fooling around at the gurus and riching up the mix but runs really strong now. I understand that the MPS thing is fairly common at the advanced age.
fadler15222 San Diego Attached image(s) |
TonyAKAVW |
Jul 13 2005, 04:28 PM
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#13
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That's my ride. Group: Members Posts: 2,151 Joined: 17-January 03 From: Redondo Beach, CA Member No.: 166 Region Association: None |
Damn. I hope its not an MPS. I really need to get this Subaru conversion on my other car done so I don't have to fool around with this crap anymore. Of course having to fool around with this crap is whats keeping me from finishing.
I think I'll first try the cap and rotor, and then see about a new ignitition module. After that I'll try another MPS. -Tony |
mightyohm |
Jul 13 2005, 04:32 PM
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#14
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Advanced Member Group: Benefactors Posts: 2,277 Joined: 16-January 03 From: Seattle, WA Member No.: 162 Region Association: Pacific Northwest |
Ever thought about cleaning up your vacuum lines and those bad electrical connections?
It always helps to start with the basics. When's the last time you checked your spark plugs? Also don't rule out the fuel injection trigger points after you have checked everything else. Did you know that Pelican has a d-jet tester they will let you use if you ask nicely enough? |
TonyAKAVW |
Jul 14 2005, 12:53 AM
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#15
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That's my ride. Group: Members Posts: 2,151 Joined: 17-January 03 From: Redondo Beach, CA Member No.: 166 Region Association: None |
So on the way home from work today I stopped by Pep Boys and grabbed a new cap and rotor. The old one was worn and had carbon deposits all over the inside, probably because the rotor sat too high on the distributor shaft. I sanded the base of the new one down 50 mils and it made plenty of clearance on the bottom for the magnet disk.
Tonight I took the car out for a spin and 15 minutes into it, the problem came back. came to a stop light, the engine felt like it was running on 1 or 2 cylinders, the generator light flashed in unison, and the engine died and the oil light came on. Started it back up and stumbled home with a single good and loud backfire. When I replaced some fuel lines recently I checked the vacuum lines to make sure everything was fine, so I think they are okay and all in place. Something that struck me odd is how the problem is almost digitally heat related. Beyond some temperature the problems are there, below it they are completely non-existent and the car runs perfectly. I'm wondering now if maybe my CHT is acting funny. I suppose tomorrow I'll measure the resistance and drive a bit and measure it again. To rule out the ignition I could drive around with my oscilliscope hooked up to the coil input to verify I'm not dropping fire pulses. How's that for EE jargon Aaron? (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) -Tony |
phantom914 |
Jul 14 2005, 09:44 AM
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#16
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non-914-owner non-club member Group: Benefactors Posts: 1,013 Joined: 24-February 04 From: Covina,CA(North ofWest Covina) Member No.: 1,708 |
Tony,
Why don't you just buy another 914? I know of one that will be for sale soon. You are very familiar with it. (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif) You can make payments. Andrew |
TonyAKAVW |
Jul 14 2005, 11:45 AM
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#17
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That's my ride. Group: Members Posts: 2,151 Joined: 17-January 03 From: Redondo Beach, CA Member No.: 166 Region Association: None |
(IMG:http://www.914world.com/bbs2/html/emoticons/unsure.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/huh.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/ohmy.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif) I am thinking that I'm getting tired of type IV engines... hmmm. I think what I should do is sell my daily driver and use the time I will ahve to finish my conversion. But that would put me 914less for a few months!!!! Oh the horror! -Tony |
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phantom914 |
Jul 14 2005, 11:53 AM
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#18
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non-914-owner non-club member Group: Benefactors Posts: 1,013 Joined: 24-February 04 From: Covina,CA(North ofWest Covina) Member No.: 1,708 |
Oh well, I guess if you don't buy it, I will have to cut it up. I tried. This will be your fault. I hope you can live with yourself. Andrew |
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bondo |
Jul 14 2005, 12:25 PM
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#19
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
(IMG:http://www.914world.com/bbs2/html/emoticons/chairfall.gif) Dibs on the bumpers! (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) |
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bondo |
Jul 14 2005, 12:27 PM
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#20
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
I'm going to be 914-less for alot longer than that! Better get a radiator for your truck first though! I'll buy your yellow one for what you paid, even though it's broken now... What a deal! (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif) |
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