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DRGrocho

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I'm supposed to be moving in 2 days, so I need this to be fixed asap so that i can concentrate on other things

 

Its a 99 Lumina LTZ, 3800 II, 12x,xxx miles

 

Cars been running just a little bit rough lately, but today when I got off the interstate it seemed to be running even rougher. At the light, I put it in neutral and revved it a bit and each time the RPM's would drop down below 500, and then work their way back up to about 1000. Then from a stop light, I hit the gas and it was hesitant and bogged down, almost like the timing was off. It threw a code so I decided to go to a local parts store and have it scanned. On my way there, there were no problems. I pull into the parts store and give it a little rev and then it dies and hasn't started since.

 

The scanner says (of course) Random Cylinder misfire, I was going 29 mph when it happened, the engine was 212 deg, the crank sensor seems to be working fine (it sees rpms).

The fuel pump sounds like its working when the key is turned to on, and without a gage, it seems like it has pressure (by pressing the pin on the schroeder valve and watching it squirt).

 

My thought was that there was no spark because there is fuel (in the fuel rail at least) and I'm fairly certain that there is air unless all the intake valves stopped working at the same time. So, since no cylinders are firing, I figured the ICM, replaced that and the relay for the ignition, and still I have a no start condition.

 

Help

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The Crank sensors purpose is not to control your tach, you cannot rule out a crank sensor because your tach is working. My best guess is in this order.

 

 

1. Crank Sensor

2. Coil Pack

3. Ignition COntol Module.

4. Faulty Fuel Injector

5. FPR

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i tried calling you and your not answering. i was going to say cps, especially since you didn't have any change after the icm. maybe broken or melted wire? if it is one coil pack, it should still kinda run?

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I said the crank sensor is fine because that was the conclusion that the guy with the scan tool came to...not because my tach is working...How can I check the CPS anyway?

 

If it was a coil pack, I would think it would still kind run, or I'd have at least a couple of detonations while cranking.

 

ICM was changed and nothing changed

 

Faulty Fuel Injector - After reading a bit, I think I may check this one, from reading it seems that one bad will kill a whole bank, and on top of that, I got to thinking and the return line seemed to be high pressure, normally if I monkey with it, drips will come out, today, there was a spray that came out. I guess I should check the resistance and do the NOID light thing to figure it out

 

FPR - how can I check it? It mostly says that on the 3.8, you can rebuild it, and its easy but doesn't give checks...

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I have a scan tool toot myself, and rarely does random cylinder misfire code rule out CPS, use a DMM to test your injectors the desired resistance reading is posted here on the forum somewhere. And usually how I test the FPR is suck on it with a vacuum pump and if fuel comes out the top of the diaphram its bad.

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So we're clear, its not the kind of scan tool that you can use at Auto Zone, this was slightly bigger and more advanced....he said the CPS was registerring something....I'll check it though, it seems like an easy enough test with a DMM...

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if your return line had a lot of pressure, maybe that is a another clue that the injectors are not firing, and the fuel is going back to the tank? not sure if that is how it works.

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Alright, my resources are pretty limited but here's what I got...

 

I checked the resistance on each of the Injectors and it is between 12 and 13 ohms for each one. I didn't have any help for most of the time so I didn't buy a NOID light and check, but I did plug my DMM into two of them and crank. I saw .1 volt fluctuation with one of them and zero on the other. My guess is that it is either a very very low voltage signal, or I didn't have one. I did however pull the corresponding spark plugs (3 and 5) and check that way, and both of them were pretty wet with fuel.

EDIT: I should have been checking Current on the injectors...will try that tomorrow

 

 

Which leads me to spark. I checked at the coil, and I only had time to check 3 of them before the battery died, but I did have probably about a 1/4" long white spark out of 3 of them (6,3,2).

 

So, I have a number 3 cylinder with fuel and spark and no explosion!

 

I tried the starting fluid, but definately could have used another set of hands, and I had no luck.

 

I have more than 10v to the CPS, but I don't know what I have with the engine turning (should be 10v, 0v, 10v...etc), but since I have spark and apparently fuel, that would mean that the CPS is sending pulses to the ICM and injectors right?

 

EDIT: Also, I saw reference of this but, I'll ask. Does anybody know for sure if the computer will shut down the whole car until the code is cleared? I have had the random cylinder misfire code before and it didn't shut the car down, but its worth asking I guess...I had the battery disconnected for about 15 minutes, but maybe it needs a code reader to actually clear it?

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So we're clear, its not the kind of scan tool that you can use at Auto Zone, this was slightly bigger and more advanced....he said the CPS was registerring something....I'll check it though, it seems like an easy enough test with a DMM...

 

My scan tool isnt what you use at Autozone either it's better as well and yes you can still refer to my list, as its hustlin just like me

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So we got it running and I noticed I was about out of Coolant....I put some in, and engine siezes. I break the starter trying to crank it, and then get a new starter, pull the plugs out, and coolant pours out of some of them before I even turn the motor

 

So, I got a 3800 Series 1 for $200. Is it the same block? Can I just swap the top ends over and call it a day?

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ha I did the same thing on a 95' park ave. hydro-locked the engine, after a headgasket job, the upperintake failed, hydrolocked the engine, all i did was pull the plugs and pump out the coolant, replaced the faulty intake manifold, and the car is still going today.

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ha I did the same thing on a 95' park ave. hydro-locked the engine, after a headgasket job, the upperintake failed, hydrolocked the engine, all i did was pull the plugs and pump out the coolant, replaced the faulty intake manifold, and the car is still going today.

 

i thought when you hydro-locked a motor, it was pretty much done for.

 

 

 

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ha I did the same thing on a 95' park ave. hydro-locked the engine, after a headgasket job, the upperintake failed, hydrolocked the engine, all i did was pull the plugs and pump out the coolant, replaced the faulty intake manifold, and the car is still going today.

 

i thought when you hydro-locked a motor, it was pretty much done for.

 

 

 

 

If you don't break a piston, rod, the crank, or crack the head i *guess* it'd run

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all depends on how it happened, when i hydrolocked the park aves engine, it has been running then i shut it off, and the cyls filled up with watter, then the car would not crank, like it was seized. then i removed the plugs and tried cranking again, water shot out the plug holes, replaced the upper intake and started it up, it smoked like a bitch for about 20 minutes burning off all the condensation, been fine for a long time now.

 

now say you were running 2000rpm or so it could have bent a connecting rod.

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Alright up date on his car. he went and pulled the upper. coolant everywhere. changed the gasket and put the car back together. changed the oil. started the car. ran for about 5 minutes. smoked at first, obviously, exhaust cleared up. shut it off went and got more coolant, came back, went to start it, broke another starter. from what it seems the combustion chambers filled with coolant again. he pulled a plug from the front, and it was dry but he didn't pull the rear, and now the oil is white. anyone have any ideas? did he blow the head gasket? crack the head? anyone have any more experience? could the coolant of gotten into the crankcase and it isn't another issue? but really there isn't much of anywhere that the coolant could drain down with just removing the upper intake manifold.

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wait wait wait.... this is an L36 correct?

 

ok now did you change the plastic intake manifold as well?

 

if not you just did alot of work for nothing, pull it again, and look around the EGR pipe i'll bet money it is leaking from there.

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he replaced the gasket, which i would assume is the whole thing. he said they saw where the failure was. so after running coolant went into the crank case.

 

 

99 LTZ with l36.

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