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Posted by: HeloMech Jul 24 2006, 05:44 PM

Ok, what's the joke? There's some type of thing that let's my car know that it's about 50-100 feet from it's destination and that's when it loads up, misfires and dies.... RIGHT?

Again, we push started the car. Started right up. Anything above 2800'ish rpms and it would sound like it was misfiring. I was able to drive it home, running 4th gear.. 2000-2600 rpms. About the last block or two, a couple of sputters. Last 100-200 feet and it stumbles quite a bit. Then, it's almost like it runs out of gas. Just for giggles, I hit the starter (since the starter was dead at work) and the starter kicked on twice.. then it was dead again. Either way, car didn't start.

The guy in the other 914 behind me said that just where I said it was acting up, he said it sorta puffed some smoke and then he smelled gas.

I've tried to put as much info out as possible. Hm, also, after it seemed like it was loading up, I'd put it in neutral and rev it a bit, trying to clear it out. That didn't really seem to have any effect... at the higher rpm's it would just sound like it was misfiring again.

so... anyone have suggestions with this info? Joe?

Thanks,
Robert

Posted by: r_towle Jul 24 2006, 05:52 PM

loose ground wire to battery..

Rich

Posted by: HeloMech Jul 24 2006, 05:55 PM

Tight at the post and on the car. (from battery to car) new battery and cleaned connections.

Posted by: lapuwali Jul 24 2006, 05:57 PM

I'm guessing you have more than one problem here. The sputtering and dying may be a plugged fuel tank vent. Carbs or FI?

Posted by: HeloMech Jul 24 2006, 06:00 PM

It's the stock DJet FI system. I know the starter is seperate from the other fuel type issue...

where are the return lines and vents located? I should be able to blow them out with low PSI air, right?
Also, if it's venting... that was a question I posted elsewhere earlier... just wondering how long that it
would typically take to suffer from a vapor lock type situation? The fuel pump is still mounted in the right rear.

Posted by: Brando Jul 24 2006, 07:56 PM

Start with the basics...

1. Good grounds/clean connections
2. Fuel
3. Spark
4. ...

Posted by: mihai914 Jul 24 2006, 08:44 PM

Carry a multimeter with you and next time the car acts up test the resistance of the CHT (head temp sensor), if it's infinity then that may be your culprit.

Posted by: Kersey Jul 24 2006, 09:17 PM

I have seen a similar problem occur on boats. In those cases a screen on the pick up tube in the fuel tank would slowly get shut off by pieces of stuff that had gotten in the tank over the years, it would take a given period of time before the engine would run bad and shut down. After sitting for a while the vacuum would let off the particles would fall away and the engines would run again. You could run these boats at the dock all day, the problem only happened when they were moving. If none of the other things straighten it out you might look at the tank.

Paul

Posted by: KaptKaos Jul 24 2006, 09:21 PM

Wait a sec.... you have a working odometer?

I had similar issues with my trigger points, but it wasn't this bad.

Posted by: HeloMech Jul 24 2006, 10:15 PM

Nope! I have another car and a bike and have worked at the same place for 3 years so I know how far it is... lol

Posted by: JOHNMAN Jul 24 2006, 10:20 PM

Just for grins, you should swap out your ignition coil. I had one that would break up badly above a certain RPM and went nuts trying to diagnose it. I temporarily tried a 911 coil and all problems went away. I then bought one the right size.

It could be crap in your gas tank as others have suggested, but I like to try the easy stuff first.

Posted by: GWN7 Jul 24 2006, 11:23 PM

Check all the stuff mentioned and only drive it 8 miles till you figure it out....

Posted by: 914 dror Jul 25 2006, 02:03 AM

I had the same thing with my `72 vw bus I ended up with pulling the tank out and (it had about 250 cc of rust! in it) had to do a sealling job on it - used por-15 tank sealler, had no problems sins (2.5 years).

Posted by: Rockaria Jul 25 2006, 07:53 AM

If the guy behind him stated he smelled gas, would that mean the tank line is clogged? or a too rich situation? Could a clogged line make it run rich?

The starter problem I have had on every 914 I have owned, Lucky me! I now have two backup systems; an added starter relay, and a remote start button. I realize its a hack fix, but it has worked great for years.

My car also did exactly what yours is doing once it got warm. My CHT sensor at the #3 plug wire was not solid and when the car got hot it would easily give and send a "Need more gas and lots of it" signal to the brain. totaly making the car bog down and smell of gas. But mine is an L-Jet, a different beast than the D-Jet. I would get black smoke before it died.

On the D-jet there is a Manifold pressure sensor. I have never dealt with one so maybe someone can chime in to problem that would associate with that part once the car is warm. if it does ever have trouble in warm cold situations.

Just my random thoughts on this,

Posted by: flesburg Jul 25 2006, 08:04 PM

Have you removed and reinstalled your engine recently?

If so, and this problem just started after the reinstall,
take the cap off of the gas tank and drive it.

I had a dying problem once, and the cause was two "reversed" hoses from the engine to the gas tank, and I was sucking a vacuum at the tank, and the fuel pump cannot overcome it, and the engine would stall. It would take 5 or 10 miles of driving to stall the engine.

Fix is to reinstall the two hoses that come to the engine from the tank's charcol filter, one blows air into the tank and the other uses vacuum to draw fumes into the intake (proper fix) or just leave them disconnected at the fuel tank end (improper fix but will work forever.