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Fri Nov 06, 2009 2:56 pm

When I unplug the MAF at idle, it runs alot better. With it plugged in, it runs very rich! It is a 1975 VW Beetle FI. My mechanic checked all the fuel stuff, and said the fuel pressure is good and replaced the spark plugs.
Thanks,
John

Fri Nov 06, 2009 3:04 pm

Usually only once.

Sorry John. :)

Fri Nov 06, 2009 3:09 pm

Haha, well hopefully this is its once :lol:

Fri Nov 06, 2009 5:46 pm

Did he replace the $20 Temp Sensor II?

Sat Nov 07, 2009 7:34 am

No, but I had that done last year sometime.

Sat Nov 07, 2009 10:12 am

Test it cold and watch the change in impedence it as it warms up.

Sat Nov 07, 2009 10:56 am

Ok, im going to try this for the first time. So I should set the multimeter to 0-2000ohms correct? And then place the positive on the metal part of the sensor, and the negative somewhere along the wire?

Sat Nov 07, 2009 11:11 am

Ok, I think I got it. Without the engine running, it was at around 1250ohms at 68F. When I started the engine, the ohms jumped to -500 and kept fluctuating. After I turned of the engine after I few minutes, the ohms were steadily dropping starting at around 927ohms.

Sat Nov 07, 2009 11:44 am

You are due for a new one. Good connections please.

http://www.ratwell.com/technical/TempSensorII.html

Sat Nov 07, 2009 11:46 am

Uh oh, just found gas in the oil!

Sat Nov 07, 2009 12:08 pm

Is there anyway a bad temp II sensor could cause so much gas that its in the oil? I searched gas in oil, and everything came up for bad fuel pump for non-fuel injected cars, but what about for fuel injected cars?

Sat Nov 07, 2009 1:31 pm

Well a TSII (when not working correctly) will make the engine run wicked rich, not lean as most people think. That is not helping. Change that out for cheap money.

Is your fuel pressure correct? That could do it. Leave the fuel pressure gauge on there until you figure this out.

By pass the cold start valve with a piece of fuel line. A leaking CSV could also do it.

Ever thought about cleaning and calibrating the injectors? That could also do it.

If you service the injectors, be sure to change out the injector seals an the little short fuel hoses. 2 good clamps per short hose please.

Both crusinperformance and witchhunter do a nice job on the injectors for about $100 or less. Send in the cold start valve also.

I didn't read your whole post but make sure the wires are correct at the starter. If the you have swapped out a small #50 terminal for the big #30 terminal at the starter, it will also cause your problem.

Is the idle by pass secrew on the AFM in the middle of its range? It should be.

Has somebody been futzing with the small silver screw in the AFM or the cog wheel in the AFM? If they have, set them back to where they started.

Start thinking about just who you now with a LM-1 gas sniffer.

Sat Nov 07, 2009 2:56 pm

Thanks for the reply, I dont know how or what half that stuff is, but this gives me a good reason to learn. Almost as good of a reason to switch to a carbuerator too though. I will for sure replace the temp II sensor, no reason not to. One question though, how does the starter terminals have to do with A/F ratio? A friend of mine replaced the alternator, and put in new battery cables because the other ones were in poor condition, im fairly sure it was running rich before he did any work hoever.

Sat Nov 07, 2009 3:06 pm

You can certainly figure this out. Whip that Bentely manual out to the FI section. Pretty complete.

Got this?

http://manuals.type4.org/ljet/

http://bama.ua.edu/~darren/boschindex.html

On a bus, the starter connections look like this (from ratwell's site).....

"
Close-up of the starter wiring partially removed. It's hard to mix up the wires because of the ring terminals but on terminal 30 you should have (1) large red wire for the alternator, (1) large black wire for the battery, (1) red wire for the heater booster fan and (1) thick red/white stripped wire for the fuse box. The large cables are usually wrapped in a beige sheath.
The red/white wire triggers the fuel pump via the double relay. In this photo you can see that I've got a hot start relay installed and the blue arrow points to one of the relay's wires. Normally the black/red wire which is connected to the blue wire of the relay connects to terminal 50 where I have the black wire from the relay. An large red wire on terminal 30 powers the double relay. All the red wires can be confusing but again remember all the ring terminals connect to 30."

Your volt ohm meter is about to pay off big time here....