graba

Hi,

After 30k of trouble free driving, my 2.3L NF with CIS-EIII in my westy is giving me a few problems:

1) long (5+ seconds) hot starts that require gas pedal to the floor [car starts immediately if I shut it down for just a short period (<1 min)] and [cycling ignition on and off a few times - to presumably build fuel system pressure -does not seem to help]

2) car stumbles when given gas when cold for a few minutes (idle is smooth and correct)

new (<1000 mi) plugs, cap, and rotor, and air filter

air metering plate is free and centered

no major vac leaks that I can find

pulled plugs about 30 min after a good drive and they appeared dry and in good condition (not leaking injectors is my assumption)

Fuel pump is stock vanagon (no check valve as far as I know) feeding fuel accumulator to filter to fuel distributor.

Fuel filter is a PIA on the syncro vans...totally blind and phillips screw is siezed so I haven't changed this...but fuel flow seems ok based on general driveability

Any idea if these two problems are related? Runs great and mileage is normal. Hot start problem seemed to start after I changed the air filter and cleaned ISV. Cold start thing seems new and could have been induced with my futzing around!

Considering purchase of JC Whitney fuel pressure guage...but am always up for haphazard replacement of cheap (say less than $50) parts!

thanks,

graba

Sergei

I had exactly the same symptoms on my MC1 engine. Even plugs looked ok, what you need to look at is inside of the cylliinder when pull the plugs out. Use a flashlight of some sort and you will see small drops of fuel, that will tell you that the injectors are leaky. May be it's a little different on NF motor, since the injectors are in the IM, but at least that's how it works on MC1 - btdt

HTH

Sergei Pokrovsky
'87 5KCSTQW, 187k miles
Anchorage, Alaska

graba

Thanks, Sergei.

I took a good sniff of each plug and they all smelled the same...FWIW.

Starting to wonder now if my fuel pump is NOT stock vanagon (thought the Audi's were in-tank but see some on ebay that are not in-tank) and check valve could be an issue.

Also 1/2-way through a tank with Techron.

Anything I can rule out at this point? Differential pressure regulator?
accumulator?
fuel pressure regulator?

thanks, graba

Sergei

long cranking usually indicates a problem either with a check valve or injectors, vapor lock might be an issue too, check sjm about it. Can't tell anything about pressure regulators - you'll need to run some tests with a pressure gauge (I think there are procedures described in Bentley). AFAIK all type 44 Audis have in-tank fuel pumps with a check valve on top.

Sergei Pokrovsky
'87 5KCSTQW, 187k miles
Anchorage, Alaska

rooster 2

consider replacing black rubber seals at base of injectors too