924Board.org

[ditch68]

Please Help! My foolishness has gotten me very stuck.

Here is my situation: I have tried everything I can (so far that I have found) to get my car through AZ Emissions.

Background: I got the car barely running, and it has the typical hot start issue, and in fact has NO accumulator. I have a new one, but the PO removed the fittings to it, so I have to source those. Not sure if this can affect running fuel pressure and therefore idle mixture somehow?

I got the car running very well (I thought) but has failed emissions repeatedly.

So far I have in the last month:
-Replaced cap and rotor
-Changed and gapped plugs
-Cleaned and tested injectors (good, cone shaped strong pattern from each)
-Checked WUR, repaired cut wire to it
fiddled (hopelessly) with the idle speed and mixture settings on the throttle body and fuel distributor.
-Checked the timing
-Brand new Catalytic converter
-CHECKED FOR VACUUM LEAKS over and over.


It is running very rich, and stumbles like a miss at idle. I tried to start at "the beginning" with both settings, and have both horribly and hopelessly whacked out.


SO. How does one start from some "known point" with the idle mixture screw moving the air paddle in the fuel distributor, and the idle setting on the front of the throttle body?

When I have made adjustments previously to where the car ran it's best, it is far too rich according to the emissions station.

I'm so frustrated. I need to get this K-Jetronic thing under control.

I can barely get it to start now.

*sigh*
_________________
Current:
1979 924, all stock.
1988 951 all track modded out and angry.

Past: 1986 951, 1988 924S, 1965 912 with '69 911T engine.

[Grenadiers]

W/O an AFR gauge, you're going to be making several trips to the emissions facility. Many things to check, from fuel pressure (control and system), stuck/open injectors, injector spray pattern/volume, CSV function, fuel pressure thingy on the side of the fuel distributor. All stuff to check besides turning the AFR screw.
_________________
'83 944 Track car.
'88 924S Track car.
'89 944 Turbo
2004 Winnebago Vectra monster RV
2012 Jeep Wrangler
2014 Kia Soul
2001 Ford F350 powerstroke

[larchie]

[ditch68]

Thanks for the replies, but...

Yes, I know the accumulator is the cause of the hot start problem, that's it's whole purpose in life. I've been driving the car without it for a while and have a jumper switch for the fuel pump relay to overcome that issue.

That wasn't what I was asking. I was wondering what, if any, effect the accumulator may have on fuel pressure at idle.

I have the Haynes manual and yes, do have all the correct equipment for a US model. I do NOT have access to a CO or other tester, hence my many trips to emissions!

But I messed with it since my post and by going slowly about an 1/8 turn at a time got it running better than ever after testing fuel pressure and the fittings on the fuel distributor and wouldn't you know, I broke one of the metric M8 1.0 x M10 1.25 ferrule fittings - the one that goes to the top line on the fuel distributor.

Anyone have a spare used one? I doubt I will find one locally.

Jeff
_________________
Current:
1979 924, all stock.
1988 951 all track modded out and angry.

Past: 1986 951, 1988 924S, 1965 912 with '69 911T engine.

[larchie]

[ditch68]

No problem, larchie! I hope I didn't seem unappreciative for the info, far from it. This car appears to me to be one which WAS well maintained by a previous owner, then sold to one before me who let it sit and didn't do squat to it, so, like you said, lots of "crud" to get through, and some "hammer mechanic" work to undo.

The links you posted will be a great help. Once I get that fitting I broke, I think I may be close.

Thanks again, both of you!



Jeff
_________________
Current:
1979 924, all stock.
1988 951 all track modded out and angry.

Past: 1986 951, 1988 924S, 1965 912 with '69 911T engine.

[Ian89C4]

Have you replaced the fuel filter?

Did you unhook the fuel return line from the fuel Dizzy to the hard return line and do the volume of fuel per 30 seconds check?

+1 on if you start fiddling with it without a wide band sensor you will be chasing it forever and will not be able to get it. Unfortunately you need a CO2 tester or spend the bones on a wide band and always be able to dial it in wherever you are.

Accumulator will not have any effect on idle pressure, the pressure is constant throughout the duration of the fuel cycle...idle to WOT. The dropping of the plunger by the air plenum is what controls the fuel air mixture.

I know the pain you are having, I could not get my '81 system to work...stupid lambda stuff, so I had to back date to a '79 fuel dizzy and set up...car works great now, but took me 3 months to figure it all out.

Hope everything works out for you...sent you a reply about your fitting.

Cheers,
Ian
_________________
Ian Edgerly
North Carolina

Current:
1981 924 SCCA/ChampCar Weissach Race Car ("Serenity")
1987 924S ChampCar Endurance Car ("Der Weg")
1980 924 Euro ("Wahala")

[emoore924]

Without tools, the only way I know to get the dizzy started in the right direction is to remove one of the fuel lines that goes to an injector, crank the mixture screw all the way lean, run the fuel pump, and s-l-o-w-l-y adjust the mix screw in the dizzy to rich until fuel **just* starts to come out of the open hole in the dizzy. Replace the fuel line and try to start. This should get you in the ball park.

Shouldn't have to tell you to do this outside and have a fire extinguisher handy, pin out. You will spill a little bit of fuel.

[ditch68]

Well, back to the drawing board. Failed again. Way too rich, still. I thought I really was closer. I put in a brand new catalytic converter, and that helped, but clearly I am missing something, or am just inept at setting this mixture (without a sniffer or something).

I have the head off my 951 and am doing a timing belt change and a bunch of other work, so car #2 is down. I may have to cave in and take it to a shop. I need to have it on the road ASAP. I get the feeling I can fiddle with this mixture forever and not get anywhere soon (like many of you have stated).

What sucks is it really seems to be running well, and is of course driveable, but I can't register it without passing the stupid emissions test. Now, if I lived in the suburb of Tucson (where I work, incidentally) I would not have to even be tested.

GRRRR. Sorry, rant over. I am just so frustrated. I love driving the car, but it is driving me...nuts.

Jeff


PS - thanks again Ian for the fuel fitting!!
_________________
Current:
1979 924, all stock.
1988 951 all track modded out and angry.

Past: 1986 951, 1988 924S, 1965 912 with '69 911T engine.

[larchie]

[Grenadiers]

Are you going to have the 951 back together in time (Nov 16/17) for the PCA DE day at Inde Motorsports Track? I'm thinking about going. The Southern AZ PCA is at Arroyo Seco at the end of October. Want to go to that too, attended that event twice. Dave.
_________________
'83 944 Track car.
'88 924S Track car.
'89 944 Turbo
2004 Winnebago Vectra monster RV
2012 Jeep Wrangler
2014 Kia Soul
2001 Ford F350 powerstroke

[Brockoli]

I have a wide band 02 sensor installed with the stock CIS. I set mine to 14.7:1 at idle. However I messed with the timing and the idle screw. I found that all three were variables in trying to get the car to idle at 950rpm with a 14.7:1 AFR. I removed my catalytic converter, EGR valve and I unplugged the lambda sensor.

I could let you know how many turns I have the mixture screw set at, timing and idle screw if that would help. I have found that barely adjusting the mixture screw (about 1/16-1/8 of a turn) would change the AFR by about 0.3.

My idle lately has been all over the place. 950 at start up then it can get stuck at anywhere from 1500-2200! which is really annoying when waiting for a light to change. I have replaced the WUR, AAV and CSV on the original engine that is currently in the car (my euro rebuild is still waiting)
_________________
'80 924 M471,Wideband O2, Full coilover susp,23/19 sways,Bilstiens,KLA Strut Brace,Roll Bar,Test Pipe,BBS RS, Willwood BBK

25% of a '87 944 Chumpcar http://straightpipe.ca/forums/showthread.php?t=2454

'79 924 Sebring Edition(Sitting)

[ditch68]

Thanks for all the great help.

I dropped it off this morning at a good shop. The Porsche mechanic chuckled when I popped the hood. "It's an old CIS system!" he says.

We talked for a while. He is going to see what he can do, check my fuel pressures and adjust what he can with the CO sensor hooked up.

If he isn't able to get it, I am going to just take it home and consider my options.

I'll let you know what happens later today. Good news is he has been a Porsche mechanic for years, worked at a dealer, and was even the "924 guy" back in the day. So he knows the cars, just has to dust off his knowledge of it because he hasn't had hands on one in a long time.

Jeff

Jeff
_________________
Current:
1979 924, all stock.
1988 951 all track modded out and angry.

Past: 1986 951, 1988 924S, 1965 912 with '69 911T engine.

[ditch68]

Well, got the car back, and went for yet another test. But the line was long, the car was starting to overheat, so I was forced to shut it off a couple times. This of course cooled the cat and I failed. But just barely! I passed the HC (final reading 97ppm, standard is 220) Failed CO (final reading 3.18, standard is 2.20) Very close.

I had vacuum leaks I did not catch, bad timing setting, the EGR valve is bad, and apparently the vacuum advance is not functioning.

He got the mixture set pretty well. I am sure a hot cat will give me a passing test. Well, I hope so. Then I can start addressing the other stuff. Runs very well now, that much I know.

I was very happy with the shop and the mechanic in particular.

Jeff
_________________
Current:
1979 924, all stock.
1988 951 all track modded out and angry.

Past: 1986 951, 1988 924S, 1965 912 with '69 911T engine.

[ditch68]