Slow crank no start

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Thatguy2017

Member

:

2003 MP5

• Nov 21, 2017

• #1

Ok so i have a 2003 MP5 and i have an issue with it cranking super slow, almost as if the engine is too hard to turn, with no start. Ive turned the engine by hand with no issues. Changed the battery and the starter.... Nothing has helped. I did have it started once and it ran fine until i pressed the clutch in then it died immediately. And when i tried to start it again it went back to the super slow cranking ordeal. Ive never had this issue and its driving me nuts lol. Thanks in advanced for the help.

 

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pcb

The Diagram Dude

:

2002 MP5

• Nov 22, 2017

• #2

Try replacing your battery lugs.
Check the wires for corrosion.
Clean the terminals.

 

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Thatguy2017

Member

:

2003 MP5

• Nov 22, 2017

• #3

Yea i replaced them. I know these cars for some reason have had issues like that however nothing changed.

 

M

MrGiggles

:

Protege5

• Nov 22, 2017

• #4

Check the grounds on the passenger side near the motor mount.

 

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Thatguy2017

Member

:

2003 MP5

• Nov 22, 2017

• #5

Will do but i dont believe its a ground issue. Im wondering if it has to do with one of the two swirches at the clutch pedal.

 

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pcb

The Diagram Dude

:

2002 MP5

• Nov 22, 2017

• #6

Thatguy2017 said:

...Im wondering if it has to do with one of the two switches at the clutch pedal.

Click to expand...

No... If the switch was bad, you'd get no crank at all.

A bad connection or bad ground could cause your symptoms.

 

P

pcb

The Diagram Dude

:

2002 MP5

• Nov 22, 2017

• #7

Thatguy2017 said:

... I did have it started once and it ran fine until i pressed the clutch in then it died immediately...

Click to expand...

That's a separate issue... You can address it once your car cranks and starts.

Your ECU was reset so it could be your IAC learning to idle the car.

 

Last edited: Nov 22, 2017

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pcb

The Diagram Dude

:

2002 MP5

• Nov 22, 2017

• #8

One of those switches goes to the cruise control unit to turn it off when you hit the clutch.
The other goes to the ECU to make sure your clutch is pushed to allow it to start and to also send the engine to idle when the clutch is pushed.

A bad connection can have resistance across it and a big voltage drop across it.
You may only be getting 6-10V going to your starter motor.

 

T

Thatguy2017

Member

:

2003 MP5

• Nov 22, 2017

• #9

So the signal wire at the starter would only show 6-10v you mean?

 

rsvinylgraphics

2008.5 MGM MS3

Contributor

:

2008.5 MS3

• Nov 22, 2017

• #10

Thatguy2017 said:

So the signal wire at the starter would only show 6-10v you mean?

Click to expand...

No, he is saying that is what you are likely getting if the cables are corroded, you SHOULD be getting at least 12 volts.

 

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pcb

The Diagram Dude

:

2002 MP5

• Nov 22, 2017

• #11

I'm talking about the fat power and ground wires.

The signal wire is working because the solenoid on the starter is kicking in the starter motor... But the fat power wires can't deliver the full 12 volts.

You could test the voltage right at the starter motor from ground to the fat positive wire, while you are cranking it.

Check all your power feed and ground wires for corrosion and bad connections... From the battery to the starter motor.

 

P

pcb

The Diagram Dude

:

2002 MP5

• Nov 22, 2017

• #12

It looks like the starter motor grounds though it's metal housing to the chassis.(I've never had mine off)

Check for a good clean connection on the fat positive wire.. #1

And check the fat wire leading away from battery... The positive going to the starter motor (black with a red stripe) and the negative going to the chassis where MrGiggles mentioned.

 

T

Thatguy2017

Member

:

2003 MP5

• Nov 22, 2017

• #13

Ok imma check that tomorrow since i have nothing else to do lol. I do know the positive terminal on the bat gets hot as hell while trying to crank it over. Burnt my hand last time.

 

P

pcb

The Diagram Dude

:

2002 MP5

• Nov 22, 2017

• #14

Thatguy2017 said:

... I do know the positive terminal on the bat gets hot as hell while trying to crank it over...

Click to expand...

Check that terminal specifically... Make sure it's nice clean wire going into you new lugs and that the wires are snug.

 

T

Thatguy2017

Member

:

2003 MP5

• Nov 25, 2017

• #15

Got 12v to it but no joy

 

P

pcb

The Diagram Dude

:

2002 MP5

• Nov 25, 2017

• #16

I don't know ?? That's all I can think of.

I still think it's some kind of connection issue.

Did you take your grounds off, clean them and reinstall them ??

 

P

pcb

The Diagram Dude

:

2002 MP5

• Nov 28, 2017

• #17

Check the voltage between terminal 1 under the rubber boot and the metal casing of the starter motor While it's cranking...
Then check the voltage between the positive and negative battery posts.... While it's cranking.

If there is a difference in voltage then you have a bad connection between the battery and the starter motor.

If both readings at the battery and the starter motor are below 8 Volts, then you have a bad battery.

 

Last edited: Nov 28, 2017

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pcb

The Diagram Dude

:

2002 MP5

• Nov 28, 2017

• #18

Thatguy2017 said:

.... the positive terminal on the bat gets hot as hell while trying to crank it over. Burnt my hand last time.

Click to expand...

If the positive terminal is hot as hell but at the same time the negative terminal isn't hot, then you almost certainly have a bad connection between the positive post and the lug or the lug and the wires going into it...