LS6427

iTrader: (2)

The other day all of a sudden while driving my engine starting running terribly. Like it was on 4 cylinders and the smell of raw gas when I stopped. I got it home and haven't had a chance to look at anything yet.

But I can hear the miss is coming from the drivers side cylinders. Whats the best way to check the coils.

No SES light. There may be a code but I can't drive it like this and my friends OBDII scanner took a **** on him.

Fuel pressure is fine.
The rest of the cylinders are getting spark because everything else is firing except for the miss I hear on the drivers side.

I'm thinking a bad coil or a real bad leaking injector. Maybe a failing coolant temp sensor. But I think a failing coolant temp sensor for 1998's causes all cylinders to miss randomly. I'll have the plugs out to look at them also tomorrow.

Thanks.

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dutinsss

iTrader: (2)

i've done it the ghetto way, which is while it's running pop the plug off the coil and see which one isn't arcing. i know you can ohm them out and it's safer and more accurate, but this has worked for me a few times when that wasn't an option.

LS6427

iTrader: (2)

So just pop them off, start the engine, and I will see the blue-ish colored sparking at the coil port?

Can I do all 4 on that side at once or should I do one at a time?

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99huggerorangeZ

iTrader: (2)

i would check you coil harness to check for any breaks/loose connection. then take a coil from the passenger side and swap it to the driver side and see if the miss follows it. if still nothing then pull the plugs.might have to do a compression test to check for a burnt valve. i have even had the rocker arm studs/bolt get pulled out the boss in the aluminum head causing a missfire.

dutinsss

iTrader: (2)

if you go with my method, i'd just do one at a time. and yea you'll be able to see the bluish spark arcing if it's firing. that being said, a lot of people would probably speak against doing it this way, but i've never had a problem with it and it's worked for me. if you have an ohm meter, it's not hard to test them that way, just have to look up the resistance that it should be within.

dutinsss

iTrader: (2)

most auto parts stores will have a book full of test sheets that explain how to test them behind the counter. they'll probably also have a multimeter you can use. if who you ask there doesn't know about it try to find a manager because they rarely use them.

LS6427

iTrader: (2)

Thanks for the info. I'll be checking it using "dustinsss" method in about an hour. I assume if the coils are all sparking, I'll put new wires on which I have, then the plugs.

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LS6427

iTrader: (2)

Had to run out for awhile, I'll be doing it tonight.

Thanks.

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fleetmgr

The one thing that a multimeter won't check for is high voltage breakdown. All it can tell you is that each side of the coil doesn't have an open circuit or a short. HV breakdown will only show by seeing what's not giving spark.

LS6427

iTrader: (2)

Well guys...listen to this wierd ****.

I went out just now, pulled the drivers side "2nd plug back" off and started it up. It sparked once, then nothing for like 3-4 seconds, then hit again, then nothing for a few seconds again, then started to spark rapidly but in no timed order while it was idling. It was all random sparking.

I then snapped that wire back on and did the same with the front coil on the drivers side....same ****.

Then the 3r one back and the back coil......same ****.

Then I went to the passengers side and pulled off the front wire and started it back up. This thing sparked once, then nothing at all after that. Nothing.

You think I have a bad coolant temp sensor?

Or is there one item that runs all 8 coils that might be toast?

So it appears that all coils are hitting in this random wacky order.

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99huggerorangeZ

iTrader: (2)

the coil packs are not going to be constantly spark,each one will spark when the coresponding piston is at TDC on the compression stroke,when recieving the signal that comes off the reluctor wheel from the CamPS and crankPS.

LS6427

iTrader: (2)

Right, but while its idling shouldn't I see some kind of set timing for those sparks? Liek say every 1.5 seconds it should spark.

I'm seei ng crazy out of timing sparks, then dead periods with nothing for like 3-5 seconds. Then one hit once and never hit again.

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99huggerorangeZ

iTrader: (2)

ya there should be a constant break between firing and dwell.

LS6427

iTrader: (2)

I'll be back, gonna limp it 2 miles to Advance Auto for a scan.

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LS6427

iTrader: (2)

Damn....no SES light...no codes.

Gonna try a new coolant temp sensor tomorrow I guess.

I know what a Crank Shaft Position sensor does when its failing and I've seen none of those symptoms yet.
But what are the main symptoms of a bad Camshaft Position sensor?

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99huggerorangeZ

iTrader: (2)

the camshaft position sensor has more to do with the firing of the coil packs. if you have a scan tool you can check what the coolant temp sensor is reading and then use a infrared temp gun to measure the temp and compare your readings,they should only be with a few degrees of each other.

LS6427

iTrader: (2)

I really don't have any tools at all. Well a couple philips head screw drivers...lol

I think I'll go get a CamShaft sensor and a new coolant temp sensor. I can return them if they don't work.

Do you know if the 3.8 L temp sensor is the same for the LS1 for 1998. I have the 3 prong and so do the 3.8's. All other years are 2 prong.

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LS6427

iTrader: (2)

Where is the camshaft sensor located anyway????

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99huggerorangeZ

iTrader: (2)

starter side of the block,you have to remove starter to gain access to the CPS.

LS6427

iTrader: (2)

Thats the Crank Shaft sensor isn;t it.

I thought the Cam Shaft sensor was under the intake? NO?


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