tlsmith1999

I am trying to get my US 78 5PSD running properly.

Problems:
Running rough, idles at about 200-300rpm, then dies.
Seems like it is not running on all cylinders.
The exhaust fumes are very rich, you can smell a lot of gas just starting it up.
It is dumping a lot of it unburnt into exhaust system. Throws some pretty impressive fire ***** out the tailpipe if you let it.
Will burn thru a tank of gas in about 80 miles. Pretty poor mileage, but you get a solid buzz by the time you get there.

Recent work I preformed prior to problems:
Replace clutch master/slave cylinders and blue hose.
Replaced a lot of bulk hose (mostly heater related).

Car ran fine for about 10 miles. During which I ran it out of gas.
Still ran fine for another 20 miles.

Then above problems started.

Since the poor running started I have:
Replaced spark plug/wires.
Tested each sp wire for spark.
Replaced a vacuum hose that runs from the distributor back.

Current issues that I know are bad:
External fuel pump is on it's last leg.
Recently ran out of gas(could possibly have clogged injectors/filter/etc..)
Exhaust system is in poor shape with many holes(possibly poor back pressure??)

Most of the above problems seem to me to lead to a lack of fuel, not a surplus.

Only other things I can think to check tonight:
Fuel quantity in engine bay per WSM.
O2 sensor.

Basically I am out of ideas, and need any help I can get,

Thanks,

SharkSkin

'78 US -- no MAF, no O2 sensor. Hmmm... Does the air plate move freely, returning to the up position when you push it down then release it? Disconnect the cold start injector and see if it improves. You may have connected the WUR line(+12v constant) to the cold start injector. How is the vac line to the WUR?

jpitman2

Get a copy of Watson's book on Bosch FI, covers k-jet/cis very well, and should give you the path to chase. Check plug colour for mixture - sooty is obviously rich. get a guage set from JCWhitney. Run some fuel system cleaner through it - some load a tank with it , and jump the pump relay for sometime to try to pick up the crud and dump it in the filter. Search here for others who have had CIS problems.
jp 83 Euro S AT 52k BTDT

soontobered84

Tim,
I feel your pain. I am currently sorting through some problems on the Jalapeno with the CIS. Basically, the PO put the wrong fuel pump on the car and then adjusted the CIS to run on that pressure. It would run great up to about 2000 RPM then run out of fuel. I replaced the fuel pump with the right one and it hasn't run since. I borrowed Roger's fuel pressure gauge and Watson book and am attempting to sort through the issues. If I come across any info that I think involves what you have going on, I will advise.

jpitman2

I would be surprised if the pump caused low pressure, unless it was very worn, or completely wrong type. My CIS car had an S4 pump on it when I got it (produces ~45psi for LH), and it happily gave me 75psi in 120F conditions. I would more suspect a blocked filter or piping. DO a fuel delivery rate test, looking for ~1350ml/30 secs out the fuel return line in the engine bay. Note also that the fuel filter specs are different between the L and LH cars, and CIS, due to the higher pressure of CIS.
jp 83 Euro S AT 52k

CAShark

devilinblack

I second the suggestion to do a flow test. You might also want to invest the $80 or so in a CIS test gauge kit so you can check the pressure at the WUR.

SeanR

I've been on the phone with Tim quite a few times about this and the flow rate from the return line was the next thing he is going to do. When we were at the Austin gathering a couple of weeks ago, the car was way rich. To the point it appeared fuel vapor was coming out the exhaust pipe.

We started with the ignition system and the vac systems and I asked him to post up here on it. It acts like it's dumping too much fuel and is drowning out the spark. My question to him last night was about the air plate being closed at idle, and checking its movement. Don't know if that has been checked yet.

tlsmith1999

The plate seems to close properly. I did not get enough time this evening to check fuel rates, but should tomorrow.

soontobered84

JPittman,
It was the wrong model pump. Used and out of an L-Jet '83.

CAShark

Bosch 69464
Fuel Pump, Electric; Secondary Pump, Front
For models with chassis serial number through 9200013, approximately 9/1978. 1 per car.



Bosch 69513
Fuel Pump, Electric



SWF/Porsche (OE) 92860801300
Fuel Pump, Electric; In-Tank
For models with production date from 11/1978. 1 per car.



The one in Blue Type is what you need for CIS, it also has a long neck on it. I did have an in-tank, but I just deleted the part on the inside of the tank since it was non-op. I may eventually put a new one in. Works fine.

LeoDioxide

Does MY 80 Euro have an in-tank pump?

jpitman2

AFAIK there is no significant difference in delivery pressure between L and LH systems - all peak around 3-3.5bar, and as I said my CIS ca rran fine with a pump meant for LH, delivering spec flow rate at 5bar. This would lead me to suspect the 'wrong' pump, or something on its outlet side, was faulty.
jp 83 EuroS AT 52k

CAShark

If you look at where your fuel filter/fuel pump are near the fuel tank. Follow the fuel hose towards the tank, if you see 2 wires connected to where that fuel hose ends at the tank, then you HAVE an in-tank pump too.

michael j wright

my 82 euro did the same thing-turned out to be a bad fuel Dizzy- got a rebuilt from one of the big three and ended my problems.