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Tue Nov 22, 2005 4:57 pm

Hi folks;

As the subject title said, The engine of my 1978 Westy (2.0L F.I.) basically has been dieing as soon as it crank, then I try to re-start the engine, but it takes several attempts for the engine to run back again. The bus run great for a few hours, as soon as I parked the vehicle and try to start it , same problem...won't start...

I check my timing, set my idle speed @ 950rpm, change plugs, change gas filter, I also put a fuel injector cleaner (Chevron Thectron), but without any positive results.

Any ideas or clues...maybe my injectors are severely clogged or any other thing that I maybe overlook...

Thanks,

Eladio

Tue Nov 22, 2005 5:22 pm

So it runs fine.. you park shut down engine. Then you turn key and it won't start again? What exactly happens when you turn the key. Do the idiot lights come on? Can you hear the engine trying to start but never does. How do you finally get it started again and then do you have any more problems while driving?

Tue Nov 22, 2005 5:35 pm

IFBwax wrote: So it runs fine.. you park shut down engine. Then you turn key and it won't start again? What exactly happens when you turn the key. Do the idiot lights come on? Can you hear the engine trying to start but never does. How do you finally get it started again and then do you have any more problems while driving?

Basically when I turn the key, the engine try to start, but not immediatly; it takes several attempts in order to finally start. While i'm driving the vehicle is running with no apparent problems.

Tue Nov 22, 2005 5:58 pm

Couple of questions first:

1) Was there a bunch of rusty crud in your fuel filter?
2) Does the fuel pump make noise?
3) Do you have any vacuum leaks? You are allowed none. http://www.ratwell.com/technical/VacuumHoses.html
4) Have you cleaned the connections on the starter? They power up the fuel pump so make sure they are 100%
5) Has this thing sat for a few months in the last couple of years?
6) Make sure the double relay http://www.ratwell.com/technical/DoubleRelay.html is well grounded.

I hope you have a Bentley manual. It is about to pay for itself.

Put your fuel pressure gauge http://www.thesamba.com/vw/forum/album_page.php?pic_id=105556 on the test port (between #3 and #4 fuel rail) and see what you get for a pump pressure. You want to see about 31 psi at idle. Do the thing where you remove the vacuum line from the fuel pressure regulator (FPR) to note the change in pressure in the system with the vacuum line off the FPR. You want to see about 36 psi. Put the vacuum line back on and rev it up to make sure it stay pretty constant at about 31 or so.

Shut the car off and leave the pressure tester on there and see what number it comes to after about 20-30 minutes. Ideally it will drop no lower than about 16 psi.

Then do the volume test per the Bentley.
Then pull the injectors and check out the spray pattern agains as per your Bentley.

Get back to us.

Tue Nov 22, 2005 6:21 pm

Thanks Randy !!

1) Was there a bunch of rusty crud in your fuel filter?
NO

2) Does the fuel pump make noise?
Totally yes, actually when I turn the key you can hear it pumping fuel, plus after several attemps to start the engine a more than normal gas smell on the engine compartment.

3) Do you have any vacuum leaks?
I'll say no, but I will double check.

4) Have you cleaned the connections on the starter?
clean as they can be, no oxidation, grease, dirt, ect....

5) Has this thing sat for a few months in the last couple of years?
Daily Driver. 10-20 per day. It was working properly...All of this situation started this past weekend.

6) Make sure the double relay is well grounded.
I double checked the relay few hours ago...every thing looks ok.

What's left to do is the fuel preasure test and the fuel injector spray pattern check...

Thanks again...good to heard from you...

Eladio.

Tue Nov 22, 2005 6:24 pm

When was the last time you had a tune-up?

Tue Nov 22, 2005 6:26 pm

mightyart wrote: When was the last time you had a tune-up?

I'll say a month ago....

Tue Nov 22, 2005 6:27 pm

Think! What did you do to it this past weekend?

Tue Nov 22, 2005 6:31 pm

IFBwax wrote: Think! What did you do to it this past weekend?

That's what basically is drivinnig me crazy...I didn't did any thing to the Bus this weekend...I'm normally pretty good troubleshooting the engine problems, but this time....I couldn't find any thing...

Tue Nov 22, 2005 6:35 pm

cold start valve?

Tue Nov 22, 2005 6:35 pm

agropic wrote: I check my timing, set my idle speed @ 950rpm, change plugs, change gas filter, I also put a fuel injector cleaner (Chevron Thectron), but without any positive results.

This may be a dumb question, but did you check your points/dwell?

Tue Nov 22, 2005 6:41 pm

If the car is running well when warm, you can forget about the rust and filters and plugs and points and vacuum leaks and double relay and fuel pressure and starter connection cleanliness, and instead focus on the cold starting mixture.
Please try this following experiment the next time the engine is cold:
Because you said you smelled fuel (rich) after cranking, try slowly depressing the accelerator pedal as you crank, this is sanctioned by the owner's manual and is designed to increase your air proportion from rich closed-throttle to leaner open-throttle, it is expected that the engine will find its favorite mixture as you do this while cranking, once it fires it will light up. Get off the gas as soon as it is firing consistently, you do NOT want to rev up a cold engine execessively.
If it does start up, try using this method any time you have starting issues, it is particularly useful when it is very hot or very cold out.
Once it is running, even after your difficult starts, how is the idle after about five minutes, quicker, same, or slower, than warm idle?
Colin

Tue Nov 22, 2005 6:55 pm

Amskeptic wrote: If the car is running well when warm, you can forget about the rust and filters and plugs and points and vacuum leaks and double relay and fuel pressure and starter connection cleanliness, and instead focus on the cold starting mixture.
Please try this following experiment the next time the engine is cold:
Because you said you smelled fuel (rich) after cranking, try slowly depressing the accelerator pedal as you crank, this is sanctioned by the owner's manual and is designed to increase your air proportion from rich closed-throttle to leaner open-throttle, it is expected that the engine will find its favorite mixture as you do this while cranking, once it fires it will light up. Get off the gas as soon as it is firing consistently, you do NOT want to rev up a cold engine execessively.
If it does start up, try using this method any time you have starting issues, it is particularly useful when it is very hot or very cold out.
Once it is running, even after your difficult starts, how is the idle after about five minutes, quicker, same, or slower, than warm idle?
Colin

Thanks Colin,

Basically that's the problem: Engine will probably start in the morning without any problem...five minutes later shut down. Try to re-start, eventually re-start with a lot of dificulty. Idle jumps around for a while, then go back to normal @ 1000-950 rmps. Runs great that morning...stop to get some coffen...again same story. Time to go home...same situation.

It's that crazy or what....doesn't matter if the engine is warm or hot...it go back to the same problem...It seem to be a problem some where in fuel system, but where ???

Tue Nov 22, 2005 6:57 pm

SlowLane wrote: agropic wrote: I check my timing, set my idle speed @ 950rpm, change plugs, change gas filter, I also put a fuel injector cleaner (Chevron Thectron), but without any positive results.

This may be a dumb question, but did you check your points/dwell?

Electronic ingnition (pertronix), I check the gap, it was ok...timing ok....

Tue Nov 22, 2005 7:56 pm

agropic wrote:
Engine will probably start in the morning without any problem...five minutes later shut down.
doesn't matter if the engine is warm or hot...it go back to the same problem...

So it is a warm/cold *restart* issue? where you do get a consistent *first start-of-the-day* but your later starts are difficult after the car has been driven but then has sat a while?
(I take back everything I suggested you could ignore)
Colin

Tue Nov 22, 2005 8:23 pm

Amskeptic wrote: agropic wrote:
Engine will probably start in the morning without any problem...five minutes later shut down.
doesn't matter if the engine is warm or hot...it go back to the same problem...

So it is a warm/cold *restart* issue? where you do get a consistent *first start-of-the-day* but your later starts are difficult after the car has been driven but then has sat a while?
(I take back everything I suggested you could ignore)
Colin

Exactly as you say Colin: "it is a warm/cold *restart* issue. Where I get a consistent *first start-of-the-day* , but later starts are difficult after the car has been driven but then has sat a while. Actually sometimes 5 to 10 minutes after the first-start of the day the engine just die and all the previous symptoms ocurr again...

Rare ???

Tue Nov 22, 2005 8:44 pm

agropic wrote: "it is a warm/cold *restart* issue. Where I get a consistent *first start-of-the-day* , but later starts are difficult after the car has been driven but then has sat a while. Actually sometimes 5 to 10 minutes after the first-start of the day the engine just die and all the previous symptoms ocurr again...

Rare ???

If it starts fine ice cold off the cold start valve, then it has a lukewarm starting problem [cold start valve no longer operating] then you have 1 of 2 things wrong: a vacuum leak or a too lean idle mixture.

After postively and I mean positively checking EVERY vacuum hose and elbow for any cracks..... look again, even look at the folds in the big S hose.

Tue Nov 22, 2005 9:14 pm

check your ignition system, especially the coil. you have some symptoms that could indicate the coil is malfunctioning once it heats up. one thing i like to say - when you think the carb/injection is acting up, check the ignition :-) often ignition issues look like induction issues.

Wed Nov 23, 2005 5:14 am

PM me with you email address and I will send you the AFC manual as a pdf file. This will make you more familiar with your fuel delivery system and will help you to better understand it.

My vote is vacuum leak as well. Don't let it drive you crazy- the system is nearly 30 yrs old and it needs some TLC, so have lots of patience/ beer on hand.

Wed Nov 23, 2005 7:51 am

agropic wrote:
2) Does the fuel pump make noise?
Totally yes, actually when I turn the key you can hear it pumping fuel, plus after several attemps to start the engine a more than normal gas smell on the engine compartment.

I am a little concerned with this answer.

When you say ''when I turn the key you can hear it pumping fuel'' do you mean you turn the key and you hear the pump? Or you hear the pump while the engine is cranking?

If when you turn the key on, you have something wrong. More than likely the little arm is bent in the AFM. The pump should NEVER run with the key in the on position. It SHOULD only run when cranking the engine [circuit 50 signal goes to the double relay and closes it] OR it should run when the engine is running [air flow moves the AFM flap and double relay closes thru switch in AFM].

I am also concerned that you 'hear' the pump. A good pump is very quiet. You have to feel it to know it is running. You need to get a fuel pressure gauge and test the pressure at the #3/4 test port. One that is very accurate and detailed in the 25 to 50 psi range.