Some ideas welcome. Cranks and stalls.
03-24-2008 | 01:05 AM
#18
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From: Quartz Hill,CA.
Cleaned up the MAF sensor with some cleaner. Cleaned up all of the plugs. Caps/rotors still look new.
Car seems to run a tad better after the MAF cleaning. Still will not idle but it will run around 1000rpm with the pedal; something it would not do prior to the MAF cleaning. Still running very rich.
Car seems to run a tad better after the MAF cleaning. Still will not idle but it will run around 1000rpm with the pedal; something it would not do prior to the MAF cleaning. Still running very rich.
Last edited by pearlpower; 03-24-2008 at 04:51 AM.
03-24-2008 | 03:40 AM
#19
Under the Lift
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I just checked yes, I get a series of click when the key is turned to on.
03-24-2008 | 04:27 AM
#20
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From: Quartz Hill,CA.
When I turn the key to the ON position (not crank) I get a series of clicks from the hood and then it stops, sounds normal.
Last edited by pearlpower; 03-24-2008 at 04:50 AM.
03-24-2008 | 06:41 AM
#21
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From: Buckeye, AZ
I would take a close listen to those clicks. There are some relays that energize, but I don't recall hearing anything under the hood unless you have the AC switch on.
The easiest test is an LH swap with another 87-95 928 buddy.
The easiest test is an LH swap with another 87-95 928 buddy.
Last edited by Bill Ball; 03-24-2008 at 03:14 PM.
03-24-2008 | 10:30 AM
#22
Three Wheelin'
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From: North East UK
For what it,s worth I had very similar symptoms recently , to cut a long story short, the fuel filter inards had collapsed, after fitting a new one and cleaning injectors/fuel lines all is now ok.
Ken
80 928 s manual
UK
Ken
80 928 s manual
UK
03-25-2008 | 01:52 PM
#23
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From: Quartz Hill,CA.
Had a few minutes to spend with her early this morning.
This is what I have so far:
1) Checked TEMPII sensor, both terminals checked out at 3.8k while cold.
2) Checked the MAF according to the text below:
Resistance between terminals 3 and 5 on the sensor read 4.5 vs. the 3.6-4.1 range it calls for.
3) I jumped 30/87 on the LH relay. I then checked the voltage across terminals 6/7 on the LH connector. I says a voltage change of 1/6-5.0 should occur if air is blown over the hot wire on the MAF. I do not even get any voltage across the terminals yet alone any change so I am suspecting the MAF is defective.
Terminals on LH connectors checked.
This is what I have so far:
1) Checked TEMPII sensor, both terminals checked out at 3.8k while cold.
2) Checked the MAF according to the text below:
Resistance between terminals 3 and 5 on the sensor read 4.5 vs. the 3.6-4.1 range it calls for.
3) I jumped 30/87 on the LH relay. I then checked the voltage across terminals 6/7 on the LH connector. I says a voltage change of 1/6-5.0 should occur if air is blown over the hot wire on the MAF. I do not even get any voltage across the terminals yet alone any change so I am suspecting the MAF is defective.
Checking the Mass Airflow Sensor (MAF) [applicable to all LH systems, beginning with Euro/ROW 1984 and US spec 1985].
Test the Hot Wire Resistance. Unplug the connector to the MAF. Connect the test leads of an ohm meter to terminals 3 and 5 of the MAF. The resistance specs are 3.6 to 4.1 ohms.
Test the hot wire signal. Connect the plug to the MAF. Remove the LH relay and bridge terminals 30 and 87.
Connect the volt meter test leads to terminals 6 and 7 of the LH connector. Blow air into the hot wire of the MAF, the voltage reading must change (~ 1.6 - 5 V).
Checking the hot wire burn-off circuit. Run the engine with the MAF installed and connected. When the engine is > 60C, rev the engine to above 2000 RPM. Stop the engine, turn off the ignition. After a delay of approx. 4 seconds, the hot wire must glow for approx. 1 second.
Test the Hot Wire Resistance. Unplug the connector to the MAF. Connect the test leads of an ohm meter to terminals 3 and 5 of the MAF. The resistance specs are 3.6 to 4.1 ohms.
Test the hot wire signal. Connect the plug to the MAF. Remove the LH relay and bridge terminals 30 and 87.
Connect the volt meter test leads to terminals 6 and 7 of the LH connector. Blow air into the hot wire of the MAF, the voltage reading must change (~ 1.6 - 5 V).
Checking the hot wire burn-off circuit. Run the engine with the MAF installed and connected. When the engine is > 60C, rev the engine to above 2000 RPM. Stop the engine, turn off the ignition. After a delay of approx. 4 seconds, the hot wire must glow for approx. 1 second.
03-25-2008 | 03:18 PM
#24
Supercharged
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I can't help but look at the obvious... do you have gas? Your gauge reads empty.
A funny story. I happened across a guy with a Viper in a parking lot. He was obviously having trouble. I approached him and asked him what's wrong. He said, "This POS won't run!
" We poked around a bit, he tried cranking it a few time and it wanted to run, just not for long. So I gave it a turn, then I asked, "Hey what's this light at the bottom of the gas gauge?" He said it was the low-fuel light and that his next stop was going to be the gas station. I told him that I suspected he was out of fuel. A few minutes later after walking over to the gas station and getting a gas can... it ran. 
A funny story. I happened across a guy with a Viper in a parking lot. He was obviously having trouble. I approached him and asked him what's wrong. He said, "This POS won't run!
" We poked around a bit, he tried cranking it a few time and it wanted to run, just not for long. So I gave it a turn, then I asked, "Hey what's this light at the bottom of the gas gauge?" He said it was the low-fuel light and that his next stop was going to be the gas station. I told him that I suspected he was out of fuel. A few minutes later after walking over to the gas station and getting a gas can... it ran.
03-25-2008 | 05:56 PM
#25
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From: Cambridge England
You measure MAF voltage on the cableform plug, not the disconnected LH ECU as your picture show us.
The resistance you measure of the MAF is fine. Tolerances are taken out in calibration.
Those manual checks are only for gross MAF failure. Quite small output deviations from spec will affect the car. We are talking about 3%
The resistance you measure of the MAF is fine. Tolerances are taken out in calibration.
Those manual checks are only for gross MAF failure. Quite small output deviations from spec will affect the car. We are talking about 3%
03-25-2008 | 09:22 PM
#26
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From: Quartz Hill,CA.
Yep, it has gas. Too much which is the problem but thanks
John and everyone else, this is exactly why one does not diagnose a car before work. Cannot believe I did that. Thanks.
Well, this is what the MAF reads, 1.6-1.82 with no airflow. Jumps to over 4volts with some can air blown over the hot wire. So the MAF seems to check out.
Well, time to break out the Bosch troubleshooting manual.
John and everyone else, this is exactly why one does not diagnose a car before work. Cannot believe I did that. Thanks.
Well, this is what the MAF reads, 1.6-1.82 with no airflow. Jumps to over 4volts with some can air blown over the hot wire. So the MAF seems to check out.
Well, time to break out the Bosch troubleshooting manual.
03-25-2008 | 09:29 PM
#27
Supercharged
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What do you mean too much gas? It's flooding? Did I miss that from an earlier post?
Go back to basics:
Fuel - Appears so.
Spark - Have you checked for good strong spark?
Air - We assume so
Compression - Again, we assume so.
Go back to basics:
Fuel - Appears so.
Spark - Have you checked for good strong spark?
Air - We assume so
Compression - Again, we assume so.
03-25-2008 | 09:41 PM
#28
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From: Quartz Hill,CA.
Running very rich. Black smoke, black plugs, black driveway , the works.
Air, have that.
Spark, yes, on all wires, cap rotor inspected again, new.
Coils check out.
Compression, have not done this though it certainly seems fine. No obvious leaks. Oil looks good.
Again, car will idle with a little pedal but it takes a bit to get there. It will run great if the pedal is stationary. Once I give it some abrupt gas, it cuts out.
I am still thinking the MAF.
Air, have that.
Spark, yes, on all wires, cap rotor inspected again, new.
Coils check out.
Compression, have not done this though it certainly seems fine. No obvious leaks. Oil looks good.
Again, car will idle with a little pedal but it takes a bit to get there. It will run great if the pedal is stationary. Once I give it some abrupt gas, it cuts out.
I am still thinking the MAF.