Sean79 5spd

I have worked on this problem for about a year with no satisfaction. Important items to note are :
This is a 79 5 speed with CIS

- EGR disconnected
- ALL new vacuum lines & gaskets
- New fuel pumps & filter
- Warm & cold control pressures within allowable range and mixture correct
- New green wire, ignition wires, resistors, plugs & rotor. Swapped ignition box with no improvement.
- New electrical wiring & connectors in engine bay

Does anyone have any suggestions as to where I might look next.

Thanks
Sean

Curt

Sean, check to make sure your Auxilary air regulator isnt leaking when hot. After the car warms up that valve in there should be shut and no air circulating through it. In fact you can pull the "S" shaped hose off it and cap the exit of the Auxilary air regulator and also cap the cold start air inlet. See how it runs when you do that. You dont need them hooked up to run anyway.

The way I found a lot of my problems was to disconnect and plug all vacuum stuff that I didnt need to make the car run. That was pretty much everything. Then I started reasymbling things one at a time with new rubber hose. Sounds like you may have done that already though.

Maybe before you try anything, try and disconnect the vacuum advance off of the distributor. See how it runs. If no difference disconnect both advance and retard lines from dist. Plug both lines and then hook up a vacuum pump on the retard side and pull abou 5-10psi vacuum. Run the car then and see what happens. I have had a major problem with my advance and retard lines or the dist. acting up. Several others came to me with the same problem but no one has been able to figure it out. I am now just running the car with the advance and retard lines tied together with one way valves attached to the retard side of the dist. This gives me vacuum on the retard side all the time, at idle and under acceleration. The car runs good like this but it isnt supposed to. Who knows you might have the same problem starting with yours. Mine started out as a "rough idle" problem and then evolved to not running at all.

I know you have checked fuel pressure warm and cold, I presume you have checked "control pressure" again I did everything you have listed above to my 79 as well. Everything checked out except I had several vacuum leaks but those did not fix the dist. or vacuum problems that still exist.

Another thing I had to do was remove the rubber boot portion of the spark-plug wire that slips into the hole in the head. For some reason mine were too tight or something and they would back themselves out of the hole and disconnecting themselves from the spark plug. I got tired of pushing them back in everyday so i pulled the black rubber end off and am running them just with the hard plastic showing. No problems so far and its been months.

Also, my green wire was bad as well. That was causing the major missing and rough running and sometimes no start situations. but thats not the problem your encountering right now.

I would really try the disconnecting of the advance and retard lines to the dist. and connect the vacuum pump. thats a quick check.

Sean79 5spd

Thanks Curt. I will have have a close look at the Aux Air Reg to see if it may be passing air during warm operation.

My distributor has only one vacuum line to it, I assumed it was for advance at high load. I will try disconnecting. This isone area I have not yet looked at.

I have hooked up a fuel gauge permanently to the line from the fule dist to the WUR to monitor control pressure so I am pretty sure it is OK.

Curt

Okay, you are correct about the advance on your dist. My dist. is a euro so they had one advance port and one retard port. but I would still try and disconnect and plug it and see what happens at idle.

Also, you should check to make sure your WUR is not leaking fuel back thru the vacuum line into the thottle body. If you pull the vacuum line you should be able to see and smell fuel if it is indeed leaking some. If it is you will have to replace the diaphram inside the WUR or get a new or used one. If your WUR has two rubber vacuum lines connected to it, it will be the lower one. The upper one is for like a breather for air.

V-Fib

Sean, have you checked for:

Air Flow Sensor Plate Stop incorrectly set

Leaking Cold Start Valve

Injection Valve(s) leaking (opening pressure too low)

Unequal Fuel Delivery between Cylinders ( comparative test)

It looks like you have already covered the other items that could cause your problem.

Anthony Tate
79/928 Silver Metallic

Sean79 5spd

Thanks Anthony. I have checked the cold start valve but not the air flow sensor plate stop or fuel delivery / pressure. The fuel pressure from the pump is 5.5 bar but I assume that through the fuel distributor the pressure is reduced.

Thanks to both of you, I needed some new areas to check to solve this problem.

Sean