Mechanics

92 , LS400,, V8 NO SPARK...

1992 Lexus LS 400 • 277,000 miles

Hi Guys, 1992 Lexus, v8, no spark any ideas, not very familiar with the Lexus, not getting spark, any help greatly appreciated, thanks.
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Pearlhickory
October 10, 2012.




Scan for codes first. Then go to teh site here under tune up it will explain how to diagnose your system.

Hmac300
Oct 10, 2012.
First thing you need to check would be power supply to the ignition coil.
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KHLow2008
Oct 10, 2012.
Ive checked relays and fuses, all seem ok, no voltage at coil packs, power supply to ignition? Does it have separate component to power coil packs? I was about to look at the crank position sensor, the car starts at times and wont other times, .

Tiny
Pearlhickory
Oct 10, 2012.
If either the carnk or cam sensor is bad the car wont' start so check both or actually all as you have two cam sensors.

Hmac300
Oct 10, 2012.
I got the crank sensor out, any particular steps to test the sensor? I hooked up my meter, im getting 1100 ohms, I looked up the average reading should be 2200 to 5000 ohms, correct me if im wrong, what about the cam sensors? Any readings I should be looking for thanks.

Tiny
Pearlhickory
Oct 10, 2012.
It may be the cranks sensor as the ohms are low but if it's cold that may be why. We havn't any specs for those. But they should have ohms as well.

Hmac300
Oct 10, 2012.
If you don't have battery voltage to the coil packs, you are not going to start the engine. Sine problem is intermittent, you caould have a faulty ignition switch or an intermittent break in the circuit due to a loose connection somewhere.

KHLow2008
Oct 10, 2012.
I got the part about lack of voltage to coil packs ive looked over most wiring looks ok, im fixing to pull cam sensors out and test them, I found a source telling me I should have between 800 to 1400 ohms on the sensor and to do a voltage test also, with sensor connected and motor spinning.

Tiny
Pearlhickory
Oct 10, 2012.
Did you check for trouble codes?
The cam sensor should be 950 to 1250 ohms for your model.

KHLow2008
Oct 10, 2012.
No codes, im trying to locate the cam sensors, cant see them.

Tiny
Pearlhickory
Oct 10, 2012.

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