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alanf_uk2002 · Joined: 31 Oct 2005 Posts: 31 Location: England, UK

Hi Lizard

Yeah been there already. Except without the bottles - that's for girls. But I did put my cigarette out so I guess I'm a bit of a wimp.

The injectors are atomizing but it's not brilliant. And they're not dribbling either. It'll be something simple...

I'll work on it over the weekend and report back on my disappointment on Monday.

Cheers

Alan

Smoothie · Posted: Sat Oct 14, 2006 2:33 am Post subject:

alanf_uk2002 · Joined: 31 Oct 2005 Posts: 31 Location: England, UK

Hi Smoothie

Interesting comment. When the system pressurised, you can move the plunger easily - just how much resistance would you expect?

There's no guarantee the WUR is good as they were both old.

The hot start solenoid can be removed so I could always have a look at this.

As for someone driving behind me....this car can't move it's own weight let alone be propelled along something as daring as a road.

Checked the TDC last night manually with no reference to the flywheel markings. When I got it to where I thought it was, I checked the flywheel and it was spot on - which was a bit of a fluke because you've only got to move the crank pulley a touch and the markings have disappeared!

The cam timing mark seems to be right too. With the mark lined up, the first lobe is on the left (10 o clock) which would give the piston time to travel down on the power stroke before opening the exhaust valve.

The hunt goes on.

Alan

TonyBray · Joined: 02 Oct 2006 Posts: 47 Location: So Cal

Alan,

You said: "The injectors are atomizing but it's not brilliant". I just went through this same situation myself. The car would flood the plugs when I tried to run it with the fuel pump relay in place. It would fire and run for a few seconds without the relay installed. On mine, I could hear the fuel injectors scream when the pressure hit them. Not a click but a high pitched scream. I replaced the 4 injectors and the air meter and it fires up and runs now. Do the test mentioned in the Haynes manual on measuring flow at the injectors. Watch the pattern as well. They should make a barely audible clicking when it runs.

BTW, I had very little resistance on the air meter. The secondhand unit I installed has some resistance. Have someone crank the car over with the throttle closed and watch and see how much movement you get on the air meter. Mine would nearly bottom out during cranking. It should only open about 2-4mm if the control pressure is right. From what I understand, it can't be the WUR as it only bleeds off pressure. When it's warmed up, it closes the return fuel which will raise the control pressure. When cold, it allows some fuel to return, lowering control pressure. If the port in the air meter is clogged, or the pressure adjuster is set wrong, then no pressure gets out to the WUR or even into the control pressure circuit.

--Tony
_________________
67 912 2.0 Type 4
94 968 Cabriolet
82 924 Turbo

Smoothie · Posted: Wed Oct 18, 2006 12:07 am Post subject:

alanf_uk2002 · Joined: 31 Oct 2005 Posts: 31 Location: England, UK

Hi Guys

I've not made much progress due to the fact the damn thing wouldn't start! Turns out that I had a repeat of the same problem that plagued the car about a year ago - the plugs are knackered. That's the second brand spanking new set - and neither have done any mileage!! Basically when they get wet they short out or something and never work again. These certainly didn't.

So a new set of plugs and it strikes up first time, sounding super sweet (for my car anyway). Set the timing to +10. Adjust mixture (by ear - no fancy gimmicks in my garage), adjust idle, and then go for revs.........and same problem.

I've got a lovely set of R1 bike carbs all ready to fit..... it is getting very close to ripping the whole lot out. Fibreglass bonnet and brand new adjustable and lowered front suspension also wait in the wings.

Back to the garage to stare in wonderment at this.....thing

Cheers

Alan

Ozzie · Posted: Wed Oct 18, 2006 8:11 am Post subject:

+10 is after TDC. UK cars should be -10 BTDC.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

John Brown · Joined: 07 Nov 2002 Posts: 903 Location: Leesburg VA

alanf_uk2002 · Joined: 31 Oct 2005 Posts: 31 Location: England, UK

Ozzie

The amount of time I've spent on this thing and I can assure you that +10 comes before 0 on the flywheel, therefore +10 is BTDC. If you add 10 on to the 0 on the flywheel it will reach that point first i.e. before top dead.

Alan

Ozzie · Posted: Wed Oct 18, 2006 4:59 pm Post subject:

As long as the 10 reaches the window before 0 TDC.

This is a turbo flywheel. if you take Z1 as zero and the -10 is similar to the mark where I tune mine.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

seanski44 · Joined: 13 Mar 2006 Posts: 532 Location: Nottingham UK

other poss is that its running on WarmUp due to bad earths - though did you check these when you replaced the WUR etc? - my car had the bogging down thing, but only once warmed up and it was that it was running on choke and massively overfuelling.

otherwise, silly question on the timing but couldn't be 180deg out could it?

where in the UK are you?
_________________
1998 BMW Z3 2.8 arctic silver & red

1981 168HP 931 S2 blue/tan leather - SOLD

1985 121HP 924 2.0l na modded - SOLD!
1992 968 lux SOLD
1989 944 2.7 lux SOLD

Nobbi · Joined: 24 Aug 2006 Posts: 1398 Location: Germany

You may have the same problem that i had a while ago. Check the marking on the flywheel, there are actually two of them,one on each side!!
If somebody fooled around with it your timing will never be allright.

See ya on the Autobahn.

alanf_uk2002 · Joined: 31 Oct 2005 Posts: 31 Location: England, UK

Hi Ozzie

The turbo thing looks like a different beast altogether. But thanks for the offer of advice - I'll consider anything at the moment.

Seanski

I've got earths running all over the place - just in case. I'm thinking it's something to do with control pressures and possibly the WUR or dirt in the system?

I'm all the way over in sunny Burton on Trent. Or rather overcast as it is today. I have had the timing running off number 4 cylinder and it still does the same thing (as you would expect). I've had the timing all over the place just in case it ran better but I've put it back to standard at the moment. Strikes up first time and sounds fine on idle albeit a bit lumpy.

The one thing I haven't mentioned is the fuel pump relay clicks continuously. Not sure if this is related to the problem as I have had a jumper wire in there and it still did the same thing.

Alan

seanski44 · Joined: 13 Mar 2006 Posts: 532 Location: Nottingham UK

Ozzie · Posted: Wed Oct 18, 2006 9:46 pm Post subject:

I dont have a pic of the NA flywheel but the 10 degree mark is on the same side from zero as the one on the turbo from Z1.
The NA flywheel has a 10 degree mark on the other side as well and is ATDC as Nobbi said.
I have also heard of flywheels being put on wrong but the valve timing would also be way out if that was the case.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance