Full Version: WTB - MPS for 1973 2.0
Need an 0 280 100 037 Mine holds a vacum and tests Ok but does not seem to work. Or can anyone test mine???
Does yours hold vacuum ? Is yours still held together by the rivets? Is your adjustment end still sealed with the original opaque yellow looking sealant?
Did you also check the electrical contacts with an ohm meter? The resistance between pins 7 and 15 should be close to 90 ohms. Resistance between pins 8 and 10 should be close to 350 ohms.
Thanx
Yes it holds vacum. I did test with a multimeter and it checked out at close to 90 and 350 as it should. I also checked for conductivity betweem the case and each terminal, and there was none, so no shorts. It does appear that some one tried or may have gotten in the back as the expoxy seal is gone and you can see there has been some attempt to remove the screw. The rivits are all sill in place.
Tonight I fired it up again, with the MPS connected, and CHT sensor unkooked. It started up, ran rough/rich, with smoke. I let ti idel for a minute then reved it a few times, but not very high as I watched the tach to be careful. On the last rev all hell broke loose and gas mixed with oil shot out of what seemed like everywhere. It was at least quart and I had to wipe up the floor and it soaked inot 2 full size towels. Lucky the exhast was not hot yet or I'd be listing FS a slightly chared 914. Best I can tell it came out the hoses that connect to the crackcase. On hose back by the oil filler, and the 2 that are down near the plugs/injectors that are toward the rear of the engine and car. That means there was lots of extra gas getting in from some where. Only 2 places I know where gas can get into the engine, the injectors and the cold start valve. I'll check fuel pressure as soon as I get a guage. Can a bad MPS cause this extra gas to get pushed into the engine?? Why would it shoot out like that???
Thanx
Yes it holds vacum. I did test with a multimeter and it checked out at close to 90 and 350 as it should. I also checked for conductivity betweem the case and each terminal, and there was none, so no shorts. It does appear that some one tried or may have gotten in the back as the expoxy seal is gone and you can see there has been some attempt to remove the screw. The rivits are all sill in place.
Tonight I fired it up again, with the MPS connected, and CHT sensor unkooked. It started up, ran rough/rich, with smoke. I let ti idel for a minute then reved it a few times, but not very high as I watched the tach to be careful. On the last rev all hell broke loose and gas mixed with oil shot out of what seemed like everywhere. It was at least quart and I had to wipe up the floor and it soaked inot 2 full size towels. Lucky the exhast was not hot yet or I'd be listing FS a slightly chared 914. Best I can tell it came out the hoses that connect to the crackcase. On hose back by the oil filler, and the 2 that are down near the plugs/injectors that are toward the rear of the engine and car. That means there was lots of extra gas getting in from some where. Only 2 places I know where gas can get into the engine, the injectors and the cold start valve. I'll check fuel pressure as soon as I get a guage. Can a bad MPS cause this extra gas to get pushed into the engine?? Why would it shoot out like that???
Thanx
You have different problems than with the mps. Could be an injector or the cold start valve is stuck full open. I've seen a csv fill up a 2L plenum with fuel. Yours sounds more like an injector. Good used mps' can run a few more dollars than you want to spend. I would look elsewhere before I condemn a tested good mps.
If you start the engine with the CHT Sensor disconnected, I would expect it to run rich, unless, of course you connect the wire to the ECU to ground.
QUOTE(pilothyer @ May 1 2012, 10:01 AM) 
If you start the engine with the CHT Sensor disconnected, I would expect it to run rich, unless, of course you connect the wire to the ECU to ground.
yep, it will run if at all "pig rich" and flood the engine.
also do a compression test to check that its not "blowby"
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