Bosch part numbers for MFI parts

[Greyn57]

Hi can some one help me with the part numbers for the cold start bits for a 2.4MFI motor please.

- 12 volt soleniod valve that screws on to the filter.

- & the heat temp sensor switch that screws into the motor and controls the cold start soleniod valve.

Thanks for any help,

[Early_S_Man]

MFI Cold Start Solenoid ... 901.110.911.00

MFI Thermo-Time Switch ... 911.617.117.00

[Greyn57]

Thanks for the part no's Early S Man.
I just checked the prices of these bits. Whoa!!! $460 notes for the Cold Start soleniod!! Ouch!!

Any one have a work around using non genuine parts? Was thinking maybe a 12v Industrial solenoid. ??

[Greyn57]

I checked on the Bosch Australia web site and found a list of the Bosch part no for the Cold start valve. Plus a bunch of others.

Injector Valve 0 437 004 003
Fuel Pump 0 580 970 001
Cold Start Valve 0 437 900 007

[Zeke]

More than one person has eliminated one or more of these parts. Unless you have a pure street car that deserves all the correct parts in place, it's a consideration. BTW, how do you know the solenoid is defective? I'm sure you tested it independently with an external power source, right? .)

[Greyn57]

The solenoid is missing from my car. Has been removed from the filter and plugged off. The temp sensor is definitly defective. Have checked it cold and it has no current flow at all.

My 2.4 engine has had all the cold start gear taken off. And has no hand throttle fitted. Custom install in a T3 Karmann.
It will start after about 10 cranks with the foot throttle floored. But I have to hold the revs up for a minute or two until it settles down to a realy slow idle.

Plan on setting up a hand throttle or electronic throttle positioner to increase the idle speed when cold.

And was thinking that putting the cold start gear back on might make the initial start a little easier on everything.

[Early_S_Man]

The cold-start system on a 2.4 isn't quite the same fire hazard as the earlier 2.0 and 2.2 engines if not properly maintained and pm-ed, though the OEM hoses to (and between) all of the nozzles should be changed after three decades!

I suggest checking with a specialist Porsche shop to see if a used solenoid could be found and tested. They appear on eBay from time to time ... that is where I found a spare.

[POKDUB]

I had similar problems starting, having to crank a lot before she would take. The solenoid which injects extra fuel (at the top of the air intakes) when the engine is being cranked, was not working. I sorted a bad grounding, solenoid now worked, but then found it drowned the engine, too much fuel. I rigged up a manual push-buttion switch to the solenoid, which I apply for about one second before crank, and she now kicks up first time. My car has no cold start solenoid, only a balnking plate.

You should rig up a hand trottle.

[Greyn57]

Just an update, I emailed Bosch Australia on the availability of the part no's in my post above. They advised

Injector Valve 0 437 004 003 - still avaialble ex Germany
Fuel Pump 0 580 970 001 - still available ex Germany
Cold Start Valve 0 437 900 007 - no longer made, no longer available.