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Mark the canuck
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Post by Mark the canuck » Mon Mar 24, 2003 3:26 pm

We need your year, engine size, D-jet, L-jet or carbs?
I don't know if I can help you but this is need to know stuff.
Also if FI first check all of your vacuum hoses.

pose
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Post by pose » Mon Mar 24, 2003 3:30 pm

Thanks, its a 75, like i said im a complete newbie so ill have to get back on which FI system it has.

I wills start by checking the hoses.

Thank you.

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Mark the canuck
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Post by Mark the canuck » Mon Mar 24, 2003 10:09 pm

No big deal, we all had to start somewhere.

Do you know the engine size? Is the air cleaner made of metal or plastic? Engine serial # ?

All these ? can help us tell what system it is.

pose
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Post by pose » Tue Mar 25, 2003 2:04 am

So it seems that when the motor has been sitting for a while, more than a couple hours or so, that it takes a little coaxing to start, meaning depressing the throttle, and even then it sometimes likes to die at low RPMs?

Im still a complete newbie, any suggestions?

Thanks again.

pose
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Post by pose » Tue Mar 25, 2003 12:59 pm

Checking the Hayne's manual, it says all 74/75 models have L-Jetronic airflow controlled fuel in jection systems.

Since mine is a 1975, I presume this to be true.

jarad
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Post by jarad » Tue Mar 25, 2003 3:05 pm

This is a stock 1.8, I believe, with L-Jetronic injection. Pose is my bro Image

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Mark the canuck
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Post by Mark the canuck » Tue Mar 25, 2003 3:31 pm

L-jet 1.8 will have a plastic air cleaner and the 2.0 D-jet will have an metal air cleaner, you could get a 75 with either engine, its important as they're totally different FI systems.

If it is an L-jet first check for vacuum leaks. The oil filler cap should have a seal on it, anouther common vacuum leak. Look for your fuel pump is it still under the car on the battery side? If it is it could be vapor lock.

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Dave_Darling
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Post by Dave_Darling » Tue Mar 25, 2003 5:42 pm

Haynes is wrong on this. 74 and 75 914s could come with 2.0 motors with D-jet FI, or 1.8 motors with L-jet FI.

Vapor lock is something often blamed, but rarely at fault. Checking the fuel pressure in the high-pressure loop on top of the engine should give you a decent indication if the car is vapor-locked or not.

Thoroughly check the ignition system--very thoroughly. Then make sure you don't have any vacuum leaks. Check for mis-routed wires or hoses, and look for broken wires as well.

Then start checking through the FI components. http://www.type2.com has some L-jet FI articles, as the later Buses also used L-jet FI.

--DD

------------------
1974 VW-Porsche 914 2.0 (Type IV powered!)

Pelican Parts' 914 Tech Geek http://www.pelicanparts.com

pose
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Post by pose » Tue Mar 25, 2003 6:10 pm

Thank you. Unfortunatly I am such a newbie, I dont know how to do the things are you describing, I have a manual and lots of ambition.

Is there some site or other reference that I could look at that might help me better understand what to do?

Thanks

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Dave_Darling
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Post by Dave_Darling » Wed Mar 26, 2003 12:03 pm

For a true newbie, John Muir's "VW Idiot Book" (don't let the name throw you) is a great source of information. Some of what John has to say is, I feel, off-base (he dislikes distributors with vacuum ports and fuel injection, for example). And some of it is not exactly appropriate for a 914 motor, which is more highly-stressed than a Bug motor. But he breaks things down into simple-to-understand pieces and describes them very well.

Most of what he writes is for the Bugs, but most of the "Type 4" motor stuff applies to the 914 as well.

--DD

------------------
1974 VW-Porsche 914 2.0 (Type IV powered!)

Pelican Parts' 914 Tech Geek http://www.pelicanparts.com

pose
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Post by pose » Thu Mar 27, 2003 4:06 pm

I was told by a mechanic that the issue is probabaly a cold start valve that has gone bad. As I've done some reseach this seems possible.

Have opinions?

thanks

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Dave_Darling
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Post by Dave_Darling » Thu Mar 27, 2003 6:15 pm

It does sound possible... Very definitely not a certainty, though.

If you have a volt/ohmmeter, you can check the plug that goes to the injector to see if one of the two pins gets +12V when the starter cranks. The other should be grounded when the temperature is "cold enough". How cold that is varies depending on who you ask...

--DD

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raygreenwood
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Post by raygreenwood » Fri Mar 28, 2003 4:15 pm

Dave is correct on the vapor lock. In fact...unless the car is raging hot on fire...inside the engine compartment, its also impossble on an L or D jet engine. If there is fuel in the tank, the pump cannot vapor lock. Since the fuel system is a loop...it pushes vapor through the system, to include the fuel pressure regulator. apor in the injectors will be gone in about 5 revolutions of the starter. It vents to the cylinders under about 30 pounds of back presure when the fuel pump is running. Lots of likely causes for this problem. Identify the system better and we can help. As far as the cold start valve....that could be a problem...but rarely is. It does sound like its acting rich...lots of issues specific to each injection system. Vacume leaks top the list of the first things to look for. Ray

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