lrpman

Is there a logic diagram in the factory manuals (I have looked and not found) that is for the Vacuum and Fuel System? What I an looking for is a sequence like at "TEMP X valve Y opens and BYPASS "Z" closes" I hope this is clear. All the help I have gotten so far has at least got me all the manuals and now the tool buying begins.
I have tried all the things that I have found searching the posts and would like to find a diagram so I can understand why a perfect running car that sits for 1 year goes to hell!

Chris_924s

Bad Fuel?

jurg

this?

michaelathome

lrpman,

You need to be a bit more specific as to the problems that you are having if you need help diagnosing them.

The above is a cool diagram though jurg. Could you send me a bigger image of that?

Michael

jurg

Sorry wrong diagram

lrpman

That is what I was looking for, but you say it is wrong? The bad fuel is a good point, but, will that cause a VERY RICH condition? I seen to be getting flamed, sorry for the DUM DUM questions but this is new to me. All my other cars took being ignored very well just the 951 got a little ticked I guess.
From the Turning of the key:
1. Car starts perfect
2. Runs 5 seconds CLEAN then BLACK SMOKE.
3. Drive car up to 2,000 rpm runs like crap, boost gauge working
4. Hit about 4500 and smooths out and runs till you back down
5. When you hit the gas BLACK SMOKE big time to where you can not see the car behind you.
6. Then clears and runs
My next attack will be fuel filter and checking the fuel system as much as possible. The tank is almost empty. I have replaced the ignition all except the coil, thinking MSD but do not kknow enough about the car to go that way at this point.
Since my signature was also removed
George Pavlisko
Car nut

lrpman

P.S. Thanks for the link "jurg" looks like great prices!

ibkevin

I'm thinking bad O2 sensor, its telling the DME to add gas--or a vacuum leak.

jurg

Sorry but after reading the post again,I was confused , I was thinking you were looking for a logic wavelength(vacuum /fuel) diagram,but glad that this is it going to help.

I'm very good working and fixing Porsches, , but no so good explaining ,
have you check all the electrical connection, look like you have some humidity or corrode connection in CU wiring system

poor starting behavior, erratic engine running,

misfiring or backfiring, or engine stalling, check for dirt or

moisture in any of the plug connections of the engine electrical

system. clean plug connections with compressed air

or a hot air blower.and use a electrical cleanings spray sold at any generic auto parts

also the Temperature Sensor

This sensor is located in cylinder head ) in the coolant stream of the under the intake manifold( the one wiht the blue cap) this sensor supplies coolant temperature information to the CU. This information

affects the air/fuel ratio (as engine temperature varies with time

during a cold start) and spark timing.so I guess that the temperature sensor got corrode during the long time the car was out of service (that happen a lot ) and now is sending the wrong signal to the CU.

Get a ohmmeter and test the T sensor

here t how to test it


Remove CU connector plug. Connect a ohmmeter between

terminal No. 13 and ground. Compare ohmmeter readings to

specifications.

TEMPERATURE SENSOR II SPECIFICATIONS
Temperature (1) Ohms
50**F (10**C) .............................................. 3300-4100
68**F (20**C) .............................................. 2200-2800
104*F (40**C) ............................................. 1000-1300
176*F (80*C) ............................................... 290-350
212*F (100*C) .............................................. 160-210
if you need any diagram or tech spec, just let me know,

jurg

later today im going to send you the bigger version.