freezer

So I ended up with the 98 Suburban 4x4 5.7L that started out with many problems.

I have replaced:

Intake Gasket (fixed twisted off intake bolt)
Distributor
Plugs and Wires
Master Cylinder
Both Rear Wheel Cylinders
Catalytic Converters
Bank 1 #1 and 2 and Band 2 #1 O2 Sensors
Battery

This cleared up all the codes. There is still a spot where the engine dies out about 20mph and over all the 5.7 have very little get up and go. It was drivable and I was going to troubleshoot fuel system next. BUT THEN...

The wife took it down to the store and when she tired to start it, it would not crank. I can jumper the starter relay and it will crank and start.

I have now replaced the Neutral Safety Switch and put in a new starter relay and still no crank. Fuse 8 - Crank has 12V all the time and when you go to start, the starter relay terminal 86 so no voltage. The other symptom is that the Dash P,R,D,3,2,1 indicator only lights on the bulb check. When running it is out.

Also, I am now getting Bank 1-2 and Bank 2-2 O2 sensor heater codes again.

Here is the diagram I am working off of:
http://www.justanswer.com/chevy/35zv...ow-in-key.html


I am really pulling out my hair on this truck. Never seen one with so many separate issues and once I fix one, a new one pops up. Any suggestions would be appreciated.

Rod

freezer

Okay, let me ask a different question. Does anyone know if the ignition starter switch could interfere with the dash shift indicator light. Or if the problem is more likely a wiring issue / neutral safety switch.

From the wire diagram at the link above, it seems like the Crank fuse should only have volts when the ignition switch is in the start position, yet my has a constant 12 V. But that would seem to have it cranking constantly and that is not the case. So i am wondering if the diagram is correct the 98.

With a new neutral safety switch, i have a constant 12 volts on the crank fuse and no voltage at pin 86 on the starter relay in any key position. I have not found any diagram that shows how the dash gear indicator light works to see how that is related to the no crank condition.

freezer

Okay, the black wire out on the starter relay had 12V. The numbers were backwards from what the diagram shows. Inspected wire harness and everything looked good. Then found a small ground wire by the harmonic balancer that was loose. Now everything is working again and the 02 sensor codes are gone.

Seems so odd that one small ground wire would cripple so many systems. The big ground wire was good and tight.

Now back the the lack of power problems!

warthogcrewchief

Glad you found the fix. You'd be surprised at how often a little ground can cause big problems!

My recommendation would be to do (I think it's called) the big 3...as soon as you fix the other gremlins. Add another ground wire (larger gauge wire) from 1) battery to alternator 2) engine block to frame and 3) battery to frame.

I have yet to do this in my Suburban, but have heard great results.

I have done this on almost all of the motorcycles I have owned over the last few years...and it does a great job of allowing the electrical & charging system to work.