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Discussion Starter #1
happy new year. been looking at the forums for a while to help me out, but have run across a problem that is driving me nuts.. my car, 95 24v, stopped, started up okay, drove home and stopped again. Lack of fuel. Checked fuel pump, it's okay, as well as pressure. here is the issue. I try to start it and no fuel. Checked relay S12b, motronic with diode, and it works. Checked relay 12A, no work. Have power to pins 30 and 86. When I put my 12v test light onto pin 85, while the relay is still in the socket,the light lights up and the pump now works. previously, the fuses attached to the system, the 15 a and the 7.5 amp, didn't work, but when I put my tester on pin 85, both fuses now work, sending power to the pump. Has anyone run across this problem? I am guessing that I will have to dive into the motronic control unit. Anyone with thoughts? Any help would be appreciated. Thanks, John
 

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what is your 'test lamp' -= a regular tail light bulb with couple wires soldered to it? It seems like your test circuit might be completing the ground on the primary side of the relay? Dont have my schematics here at the moment tho////
 

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Discussion Starter #3
its just my regular 12 v test light. yes, it seems like the ground is being complete. wiring is not my strong suit, i am always learning.

thanks, john
 

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Normally the motronic ECU grounds pin 85 when it receives signal from RPM/Timing sensor next to front crank pulley. So by you grounding pin 85 you are doing the job for the computer.

Now as to why it is not working, it could be something wrong with that crank sensor or the 3-wire Bosch connector going to it. Check that connector which I think on the 24v model is located under relay cover behind right headlight near alternator.

If you have to go to front crank pulley area to check sensor also inspect the front crank pulley for damaged to molded rubber damper in center of pulley (24v engines only).
 

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Thanks Steve, Checked all the connections on the driver's side yesterday and greased, dielectric, them. Now time to do the rest. I will check the damper as well as the timing belt and timing. We will see what happens. I failed to note that after jumping the pump, engine turns over but does not catch. Timing sensor may be the culprit. If need be, I will pull the sensor out of the "Q" and put it in the "LS" and give it a try.

Thanks, john
 

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Thanks Steve, Checked all the connections on the driver's side yesterday and greased, dielectric, them. Now time to do the rest. I will check the damper as well as the timing belt and timing. We will see what happens. I failed to note that after jumping the pump, engine turns over but does not catch. Timing sensor may be the culprit. If need be, I will pull the sensor out of the "Q" and put it in the "LS" and give it a try.

Thanks, john
You mentioned the S47 15A fuse for fuel pump and S45 7.5A fuse for O2 sensor heater but you did not mention the S46 3A fuse for the actual motronic ECU. It is located along with the other two and the relays on the top radiator support. Is that fuse OK? It is the ECU stay alive fuse and hot all the time (red-purple wires in and out to ECU).
 

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Discussion Starter #9
hi guys, just pulled the spark plug boot and stuck my tester in. guess what? no spark. The quest for the answer continues. Time to start the test procedures.

Thanks, john

I'll let you know how it progresses.
 

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Discussion Starter #12
fuel

Well, here is the latest. Took the engine down to the cams and access to the timing belt. Belt was off by 4 teeth, how, I have no idea. Reset the timing, checked the marks and turned it over by hand, no interference. Turned over by key, guess what, now i have fuel. Time to put it back together and see if this puppy will start. The only issue I found was the rt side cam, exhaust, was about 1/16 of an inch off, all others lined up just fine. I will let all of you know how it turns out. Thanks,

John
 

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If you were off 4 teeth you better do a compression check on that head before you put it back together. What timing marks on cams did you use? Did you have timing dies?
 

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Discussion Starter #14
have the dies and did a compression test. a little off on cyl #4. I am sure that I have a bent valve. compression came in at 150 for cyl 4 and 190-195 for the other five. Used the cam marks also. am just about to go into the garage to see if I can fix that last 1/8" off on the exhaust cam for cyls 1,2,3, might be off by a tooth. If in fact i get it started, then it will be time to get into a punch list of stuff, head, water pump, pulleys, belts, and while it is apart, I have to do the clutch and pressure plate. Fun, fun, fun.

When that is all done. I have to get the Q ready for the June meet in Warwick. Looking forward to that. If I really get ambitious, I will have the 92 L ready also.

Thanks Steve,

John
 

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You can loosen slightly exhaust cam pulley bolt, knock pulley loose off the taper and fine tune the timing that way and then hold pulley with pulley wrench and cam with timing die and retorque pulley bolt.
 

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Discussion Starter #16
After due consideration, I ordered the parts today, yea, I am gonna pull the head. Might as well, I am halfway there. Looks like the whole problem started with the timing belt, a little stretched. It only had 20,000 miles on it. Oh well, live and learn. Steve thanks for the timing advice, it may come in handy.

Thanks,

john
 

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Discussion Starter #17
well, hopefully tomorrow is the day. Head back on, cams in, with locks, new water pump, new hoses done. Time to put the rest together. Working on a friends JD 510 this morning and then diving into the alfa. Hope to have it running tomorrow.

john
 
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