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2001 8.1 Allison ABS Brake Light Probs

REKIII

By REKIII
in Ask A GM Technician

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REKIII Enthusiast

REKIII

Posted
Posted

When I first bought the truck (at 106K miles) it would randomly require 2 trys to start.

 

I would try to start it, let it crank for 5 seconds, stop then turn the key and it would start instantly. I was told this was the ignition switch failing so I bought one from a guy on here and ripped me off and never sent it, so I haven't replaced it yet.

 

Then I got a Westers computer. Very good mod, love the extra power and MPG. However, recently (about 3 weeks after installing westers) it is now randomly taking 3 trys to start and if it does start on the first try the ABS and Brake lights stay on, and the ABS doesn't work when this light is on.

 

Any ideas, I really doubt the westers is causing any probs, but there is going to be snow in a couple of months here and ABS would be nice.

 

Thanks for any help.

 

Bob

GM-Tech Senior Enthusiast

GM-Tech

Posted
Posted

It'd be nice to know the ABS code before taking a wild guess. It might be related to voltage.

 

The starting problem *may* be related to loss of fuel in the line when you shut it off. That is, the check valve in the pump is bad, allowing the fuel to drain out of the line. Then it takes a lot of cranking before the line fills back up before pressure can build and allow the vehicle to start. You need to put a fuel pressure gauge on it to see if it holds when you shut the vehcle off.

 

I'd want these basic diagnostic questions answered unless you want to use the shotgun method of repair.

REKIII Enthusiast

REKIII

Posted
  • Author
Posted

What is my best bet on getting the code, and where do I want to connect the FPG to get a decent reading?

 

I prefer not using the shotgun method either and appreciate the help.

 

Thanks

 

Bob

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