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  #1  
Old 09-14-2006, 10:14 AM
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Join Date: Sep 2006
Posts: 4
Angry Help Will not start

1990 300e 200000 miles
bought used 2 years ago.
Drove home last friday night got up to go to work on sat will not start.
cranks but no spark. can hear the fuel pump run after cranking short time.
removed the dis cap and found the center botton came loose replaced the cap and rotor botton. also found small amount of oil in the dis cap. cleaned and installed the cap. still will not start. on the way home one night i did smell something that smell hot.

i have found no fuses or relays damaged.
What do the two reference sensor OHM at . How would you check the coil to see if it is bad.

Were should I start looking for the issue that is keeping it from starting.

The Fuses at the ovp test ok with DMM. I hear the fuel pump running after the switch is off for just a few seconds. I have tested all plug wires and griunded the plug with the tester (lookes like a plug with a clip on the side. Still no spark at the plug ends.
There is a small amount of oil in the disp cap. Is there a set of pick up under the plate should I try to clean this with spray parts wash.


thanks


Last edited by Klone; 09-18-2006 at 02:32 PM. Reason: Need more info
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  #2  
Old 09-14-2006, 11:27 AM
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Wait if it will not start How were you driving it home
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  #3  
Old 09-14-2006, 11:45 AM
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Location: Southeastern PA
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Install a new distributor cap, rotor and O-ring. Also check the condition of the ignition wires and spark plugs.
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  #4  
Old 09-16-2006, 07:47 PM
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Quote:
Originally Posted by amartin2 View Post
Wait if it will not start How were you driving it home
Started at work drove home about 30 miles. Has not started again.
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  #5  
Old 09-16-2006, 07:52 PM
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Quote:
Originally Posted by Ferdman View Post
Install a new distributor cap, rotor and O-ring. Also check the condition of the ignition wires and spark plugs.
Installed new cap and botton. Do you thank it coulc be the coil.
I have had no issues with this car.
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  #6  
Old 09-16-2006, 07:57 PM
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Can the OVP cause this problem?

Klone: do a search for OVP - I think you will find useful info, even if this gadget is not the source of your problems.
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  #7  
Old 09-17-2006, 09:51 AM
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Join Date: Jul 2003
Location: Richmond Hill
Posts: 149
Advice re: no start

Please do your self a favour and don't start replaceng parts without knowing they are bad. Check for spark ONLY at spark plug leads NOT at coil lead otherwise system damage could occur. make sure plug is properly grounded when checking for spark.

You must hear the fuel pumps (under car just forward of right rear wheel) operating for about 3 seconds when ignition turned on. Fuel pumps should also run while cranking, otherwise will not run unless engine is running.

Fuel pumps are controlled/powered by the MAS control unit which is behind the black plastic panel at rear of the battery.

The easiest way to check for power to the pumps on your car is to find the single pole (wire) connector in the front passenger footwell, on the right side at the top. Pull on the top front corner of the side panel to expose this wire and connector. Use a flash light...you may have to feel for it. You must have minimum 11.5 volts at this wire coming from the MAS unit WHILE CRANKING engine. If you don't find this connector remove the rear seat, there is a two pole (two wire) connector near the vacuum pump. One wire from this connector goes directly to the fuel pumps, you may test for 11.5 volts here ( while cranking).

If the fuel pumps do not operate and you have 0 volts in test above, you may remove the MAS control unit (carefull it's expensive) and disconnect the battery then bridge pins 1 and 2, reconnect battery and listen for the pumps working as you try starting. If the engine starts with the pins bridged, this indicates that the circuit in the MAS that controls the pumps EDIT: COULD BE bad. They are repairable. This problem may be noticeable after the car has not been used for several days and often will run well until about 10 minutes (temp related) of driving. Problem could be caused by related circuit feeds to the MAS control unit.

Hope this helps.
Acky

Last edited by Uncle Acky; 10-24-2007 at 10:22 AM.
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Old 10-24-2007, 10:18 AM
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Critical update to post

Hello, here is an important update to my post on mas control unit operation.
When checking for power from mas to fuel pumps (from terminal 2 at mas);

You MUST have the following at mas connector plug;

Terminal 1 - battery voltage, not fused
4 - ground
10 - battery voltage, in start/run, from ignition with ignition ON
12 - 10 volts, start signal, while cranking engine only
16 - 4.5 volts, td voltage signal from EZL ICU while cranking engine only
21 - 11.5 volts, fused, from OVP Relay, with ignition ON

If any of the above is not present a good mas unit will not supply power to the fuel pumps. The engine will either not start or will start but will not run. Do not replace mas unit just because it fails to power fuel pumps. (using a proper guage jumper wire from pins 1 and 2 should only be connected while the battery is disconnected otherwise it will arch and pose a danger being close to the battery) once jumpered, connect the battery to test the pumps only, pumps should run with jumper in place. NEVER DRIVE THE VEHICLE WITH JUMPER IN PLACE!.

I think that of the above, lack of battery voltage at terminal 21 of mas unit from the OVP relay would be the most common fault. Repairing or replacing OVP relay should solve the problem.

I apologize for any confusion or misinformation from my previous post
aCKY


Last edited by Uncle Acky; 10-24-2007 at 08:00 PM.
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