Tagahoe

'98 tahoe 2door 5.7 4x4 wont turn. when i turn the key to 'start' nothing happens, except for ac working, lights working, radio working, but when i say nothing happens, i mean starter wont turn, fuel pump wont turn on, gauges do nothing, not abs light comes on, no dash lights come on like they normally would.
yesterday, my oil pressure gauge dropped to zero, and my check gauge light came on, then my oil pressure went back up to normal. I checked my oil and it was good, so i thought it was my oil sensor (sending unit). upon looking for it today, i found that my knock sensor wire was burnt about 6" from sensor, i guess it burnt from the exhaust manifold. could this be the problem?
i tried finding the other part of the wire that burnt off, but i can not locate it, its like its gone . i tried tracing it back from the ECM, but im not sure which wire it is. the schematics in the haynes manual doesnt help much, besides saying it goes from the sensor to the ECM. no pin number or plug color !
i tried jumping the battery, and that did nothing, cleaned the terminals and nothing.

horse482

You may have a problem with your ignition switch. Have you tried testing the starter to see if it even works? Knock (denotation) sensor just senses knocks or pings in the engine and will retard the timing when they are detected to stop the pinging. I would look to see if the ignition switch has come loose or has just gone bad. It is at the botom of the steering collum near the fire wall.

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NO 4 N JUNK

1994 GMC K1500 XC 5.7L
2004 Chevy Avalanche 4X4 5.3L (sold do to gas prices last year)
2007 Chevy Impala

Tagahoe

thnx, i will go out and check once it stops raining. it does sound like something isn't 'clicking.'

horse482

Let us know.

__________________
NO 4 N JUNK

1994 GMC K1500 XC 5.7L
2004 Chevy Avalanche 4X4 5.3L (sold do to gas prices last year)
2007 Chevy Impala

777stickman

Looking at my '98 C/K manual. There are 5 contacts in the ignition switch. 3 of those contacts power the things you have described. Those 3 contacts are powered by the IGN A-fuse 6-40a in the underhood fuse block. REPLACE that fuse even if it looks good and post back.

The knock sensor wire being burnt will set a code for that sensor system and turn on the SES light but will not cause the trouble you are having.

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"R57 3CAR" 210 2dr post. 420HP 355 F/I 4sp 3:42 posi. (Dale Earnhardt tribute done by me.)
75 GMC Vandura 3/4 Ton
78 Chevy K5 Blazer
98 Chevy K2500 Suburban LT/7.4
05 Dodge Ram 3500/Cummins (Wifes horse hauler)

Tagahoe

all the connections look good and connected under the steering column.
I will try fuse 6-40A, and let u all know.
Thanks.

Tagahoe

turns out, it was the 40amp ignition fuse under the hood. goota love quick easy CHEAP fixes.
Thanks guys!
if anyone knows where the knock sensor wire goes to, please let me know. I know it goes into one of the connectors on the ECM, but im not sure if it goes on the white, black, blue, or red connector. Its a huge bundle of wires.