Is it too Rich?

[deoxford]

Today I took the car for a drive to the gas station, this was the first time it been out for a ride in a long time(10 years)
Any way I have two Proubems

1. I think the M/C is bad because it stops and the pedel is firm , then It gett soft and you have to pump it back.


2. THe car bucks really bad in first , If you let the clutch out till the RPM's get high. All the rest of the gears seem to be fine.
I was thinking that the MFI is too Rich , I noticed that I smell gas in the exhust..

What do ya'll think , to rich? How do you adjust it?

THe car is a 72 , with a 73 2.4T MFI

[LeafGreen]

Based on your description of the M/C, I would suspect it needs attention, as well as the rest of the brake system.

The bucking problem could be a bunch of different things, but it may go away after the engine is tuned.

I have found that adjusting the MFI is not done by just turning a screw, it is a series of adjustments including: throttle blade angles, pump lever angle, ignition timing, the two mixture screws on the pump...........It is unlike anything I have ever adjusted. If you really want to go after it, you need the Porsche "Check Measure Adjust" manual, a couple of special tools and a lot of patience. Here are a few things you can do without any special tools that will save you a lot of headaches.

1) Make sure the hot air hose (~1" dia.) is connected from the driver side heat exchanger to the thermostat.

2) Make sure the cold start valve on top of the fuel filter is not leaking and dumping extra fuel into the stacks.

Also, see my thread on this site "are there any good MFI people out there?" lots of good info. posted by very knowledgeable people.

Good luck.

[deoxford]

Alex,
You are right on the M/C a new one is order and on it's way. The M/C was the only thing I did not do when I restored the car, new Carrera brakes in the front , new SS lines and new Hard lines with new "M"s in the rear. But I was a bit lazy and did not do the M/C.
As for the MFI, I did read the CMA and looks like a lot of things for me to screw up. How do you check the cold start valve , I put a new hose on the Thermostat, Still the same. I will look in to the Cold start valve.

Thanks
Derek

[LeafGreen]

Derek,

A simple way to check if the cold start valve is dumping fuel is to pinch off the hose with vise grips and see if the engine leans out (mine did), you may want to slit a piece of 5/16 fuel hose and wrap it around the smaller fuel line to avoid damage. Cutting off the cold start fuel supply to the stacks is the best way to take this circuit out of the system.

You should also check if the solenoid is electrically on by disconnecting the wire at the top and listening for the click. If you have 12V at this wire when the engine is warm, then you have more problems, and I can probably help with those too. Again, see my other MFI posts showing the speed switch and factory wiring diagrams.

[deoxford]

Alex,
Ok Here is were I am at, the new hoses came in today and I went out and put them on and there is no change.

So here is the question, why would it be to rich if it does don't do this in reverse? It should do the same in Reverse. but it does not.

In first the car will slowly roll,and when the clutch comes all the way out it bucks and stalls, the same in second. Now put the car in reverse and you can spin the tires, this makes no sense of the fuel being to rich.

One friend said that I am not getting the car in gear, can that be is the trans bad? He think that the linkage needs to be adjusted. what are your thoughts?

Grady, do you have any thoughts on this, I was hopeing it was the trans mounts but no luck.
I did go back and read the MFI threads, I don't think the apply because the reverse issue
Thanks
Derek

[LeafGreen]

Derek,

Sure, what you said about the reverse situation makes sense. I have some other thoughts regarding the bucking problem. You mentioned the car was restored, which I assume the engine and trans were removed and reinstalled at some point. If so, then what I am about to describe can be the source of your problem.

There is a flexible tube between the floor pan and the tranny that the clutch cable runs through; it is my impression that this tube MUST have a bend in it. If the engine was R&R'd, is it possible this tube is not routed correctly after installation? I just looked at my car (72T) and the tube comes out of the floor pan, making a nice arc as it runs over the throttle bell crank, then drops down and pilots into the tranny. I had a 65 Bug with a bad bucking problem, and the solution was to shim the flex tube until an arc was established. Bada-Boom--Bada-Bing! Problem solved - just like that!

I hope this is it - I'm running out of ideas.

[deoxford]

Alex,
That does make sense , And I did have to route the cable to the side of the thottle linkage. I put it there because I was having a thottle sticking problem . Hence it may be a bit staight. I will get under there when I get home from work , I want to run out there tonight, but the wife is asleep already. Don't what to wake her up.

Thanks for the help

Derek

[deoxford]

Alex,
I worked on it a little tonight, I found the cable was in fact not arced. I moved it to the correct location and maybe we have something.THe car is really stalling now not really bucking. I wonder if I have the clutch adjustment correct.
How far does you clutch pedel go do before it is engaged ?
Can you take a pic of the clutch fork on the trans ?
I wonder is the angle is correct. Maybe this is just a adjustment issue.
Also how much do you rev the car up in first? I read out the clutchs on these car as be weak so I hate to blow it.
Thanks
Derek

[LeafGreen]

Derek,

Good! We're getting somewhere.

Funny you should mention the stalling during starting out.... My car has the same problem, which at times requires fairly high revs to get past the flat spot. I have been working on this problem over several months, and leaning out the mixture seems to make the symptoms less evident, but that may be putting a Band-Aid over the real problem, such as ignition problems.

I went to take a picture tonight but the batteries were dead, I'll try to put something up tomorrow. I will also drive my car to work tomorrow so everything is fresh when I make my next report.

[deoxford]

Update time,
I looking at the Thermostat to see if it is working correctly, and cleaning it.
As I looked on the MFI pump I noticed this , I thought that this was covered with a hex bolt then you put a screwdrive inside to adjust to rich of lean. Does this look correct.
Also the micro switch does not look correct, should it be off when the engine off?