Author Topic: Can a M42 motor come out of time? (Read 23623 times)

RED IS 91 · « **Reply #15 on:** January 13, 2009, 10:43:20 AM »

I doubt you have moisture living in an arid climate.If you have a fuel pressure tester then you should have around 42psi at the pump.
Check the basics first.
Fuel
Spark
Compression

good luck

rallyegolf · « **Reply #16 on:** January 13, 2009, 04:04:59 PM »

I am going to pick up a compression tester on the way home from work today and test that.

For the fuel pressure, you say to test 42lbs at the pump. Are you saying 42lbs is what the pump should be pushing before the filter and before it gets to the fuel rail? Also do we have secondary pumps on our M42's?

RED IS 91 · « **Reply #17 on:** January 13, 2009, 05:08:07 PM »

On the supply side of the pump which is under the rear seat .When you connect your fuel pressure tester you should have right around 42 psi .When you connect the tester and turn the car over that is the pressure you should have. Follow the directions that come with the tester.They usually have some adapters .
The M42 only has the in tank pump.
The arrow is to the supply side .

rallyegolf · « **Reply #18 on:** January 13, 2009, 05:24:55 PM »

Thanks RED!!!

highwhitey · « **Reply #19 on:** January 13, 2009, 05:52:25 PM »

make sure fuel filter aint blocked and theres power getting to the fuel pump!!! cause i had same symtoms and the filter was blocked and the fuel pump circuit ended up shorting!!!!

rallyegolf · « **Reply #20 on:** January 13, 2009, 10:13:37 PM »

Quote from: highwhitey;64609

make sure fuel filter aint blocked and theres power getting to the fuel pump!!! cause i had same symtoms and the filter was blocked and the fuel pump circuit ended up shorting!!!!

Thanks, Today I got a fuel pressure tester and this week, I will test at the pump, and test at the fuel rail to make sure they are close to the same. If not, I will start backtracking to the pump and see what's stopping the fuel.

Quick question, how accurate is my cylinder compression test going to be if I cant worm up the motor first?

RED IS 91 · « **Reply #21 on:** January 14, 2009, 06:38:05 AM »

Quote from: rallyegolf;64616

Thanks, Today I got a fuel pressure tester and this week, I will test at the pump, and test at the fuel rail to make sure they are close to the same. If not, I will start backtracking to the pump and see what's stopping the fuel.

Quick question, how accurate is my cylinder compression test going to be if I cant worm up the motor first?

With a cylinder compression test your looking for even numbers across the board.If one is way off then you'll have to look deeper.I doubt that that is why it's not starting but it will tell you the health of the motor to some degree.

rallyegolf · « **Reply #22 on:** January 14, 2009, 01:05:50 PM »

I will report my findings. Of course I have problems 2 weeks after I post the car for sale.....

rallyegolf · « **Reply #23 on:** January 14, 2009, 09:45:35 PM »

Okay update.

I tested the fuel pressure from the fuel line that goes into the fuel rail. The lower silver line into the rail is where I tested. I have great pressure. So onto the compression of the cylinders.

dry test.
1=120
2=150
3=75
4=70

after a little oil in cylinders
1=120
2=180
3=120
4=120

I tried the 2nd cylinder again,and hit 150 after the first 180. "harbor freight compression tester"

So I think the compression was so low because the motor was cold, but it is at least every cylinder sucks the same amount. "kind of"

I think I need to remove the intake manifold next and test the resistance on the injectors and test the fuel pressure regulator. Can I test the regulator, or do I just replace it?
How can I tell if my ECU works correctly? Maybe that is what I need???

What would you guys check?

RED IS 91 · « **Reply #24 on:** January 15, 2009, 04:50:59 PM »

Have you checked for codes

rallyegolf · « **Reply #25 on:** January 15, 2009, 09:13:27 PM »

Yeah, code is 1444= running okay

go figure.

RED IS 91 · « **Reply #26 on:** January 16, 2009, 08:11:57 AM »

When you pulled your plugs for the compression test were they wet from fuel ?

rallyegolf · « **Reply #27 on:** January 16, 2009, 06:58:59 PM »

Quote from: RED IS 91;64793

When you pulled your plugs for the compression test were they wet from fuel ?

no, they were pretty dry. You think I have a bad fuel pressure regulator or bad injectors?

RED IS 91 · « **Reply #28 on:** January 17, 2009, 07:17:42 AM »

What did you have for a fuel pressure reading ?
Are you sure that you cam position sensor and crank position sensor are good and the connections are clean?

rallyegolf · « **Reply #29 on:** January 17, 2009, 09:30:10 AM »

Yeah. Both sensors are working okay and connections are clean. I did the ohms test and they were 1280 and 560. As for the fuel pressure. The guage maxed out. Shitty guage, but there was deffinatly pressure.
I think I'm going to pull the mannifold and test the injectors next. Anyone know how to do that?