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Help find out whats going on with my 1st front left cylinder

W

wild2crazy

New member
Ok long story short my father gives me a 2000 gtp 3.8 supercharged before he had the piston replaced and told me he felt the car never ran right since then.
I notice about 3 weeks ago its running real rough when trying to take off it stutters. i check around and notice the vaccum line tee to the super charger/intake manifold was cracked so ordered new from GM still get a rough idle so i clean the coils check the plugs and notice the front left cylinder spark plug is completely bent in(WOW) almost like it was dropped when being reinstalled after new piston and rings put in. So i changed all the plugs car runs smooth again oh got a p0300 (cyl misfire) but after fixing that plug that went away. Then she stays quiet for a day then i get a p0113(ect circut low) noticed car never rose above 70 degrees so low and behold i found out the thermostat was stuck open all the time, replaced and made that code go away.Then the nice car just as i recheck all my tools are put away i notice my idler pulley for SC AC is completely gone and belt is just laying on top, So i run to the GM and get a idler pulley pop that on and good to go again she stays quiet for a day and what do you know the magical check engine comes on again p0114 (ect circut high) found out yellow wire at connect direct on ect sensor was pulled right outta the terminal so the pcm had no idea what temp the car was actully running at, so soldered that connection light goes out happy happy and now tonight the big one.

always heard a chatter around the supercharger front left did some research most people say it was the coupler inside, I was starting to think that. until i pulled away from work tonight and that rattling noise was really happening now louder then before and little white smoke coming out exhaust check engine light comes on and not only does it come on i can only do about 40km/h and stutter is crazy but get quieter around 1600 rpm. i pull over and take off the supercharger /AC/tensioner/idler pulley/ belt and notice that the noise is still there(Damm not that coupler like i thought) let it idle for a 10 mins to find where that knocking sound is coming from i get the flashing check engine light now which means shut down time. But it never did so i figure why not lets check that 1st front left cylinder spark plug lets see if its bend in again, well after trying to change a spark plug in the middle of the night just to get home work i noticed that the spark plug was filled with oil sludge and completely detonating black so i go buy a new one car runs better enough to get me home but that rattle sound was so loud i pretty much struggled to get to 60 but after that car was smooth all the way up to 120km/h to get me home.

oops forgot something don't know how ****ing car been ****ing killing me i was pulling into GM to get the vaccum line way back then hop back in the car and get a low oil light which was strange i have a look and she was only down a little bit maybe half a quart i fill her up and lights gone now before the rattling that light came back on again low on oil so i fill her up wondering where the hell the oil is going there's not a leak on the car and absolultey nothing in the antifreeze rad or spill over container. (yay no head gasket leak at least) but now i notice the oil is going directly into the resonator exhuast which means its getting into the combustion chamber then out the exhuast valve.

all this happens in a span of 2 weeks well now iam stuck here and asking any suggestion which might be happening to my 1st piston the check engine light is on and sometimes flash but wont get access to my scan tool till tomorrow to pull codes.

thinking that there"s oil all over the spark plug that must mean i got a piston ring gone correct? is it possible to get oil in there if the piston was chipped from the first time the mechanic replaced it and then it bent the spark plug, funny thing now is its not bending the spark plugs now. but just to do my short trip home that new spark plug is toast thank god they come in 2s lol. is it possible that it could be the head or a rod could cause this sound and oil getting in?

Any suggestion would be very helpful cause iam at wits end with this car right now.
 


There are several possible scenarios. All coming back to that cylinder: Rings are stuck, piston is damaged again, cylinder wall is hosed, etc.

Since you have chatter and not a knock....and if I understand correctly, the new spark plug is bent, too......its possible the wrist pin or wrist pin holes on the piston have taken a crap. Could be a pricey fix to do it right. If there are quite a few miles on it, you may be best to hunt for a lower mileage engine in a salvage yard or Craigslist and just swap the entire engine out.
 
This sounds like it has a spun bearing on the crank, or a rod bearing. The power issue and the car eating spark plugs makes me think its self-destructing from the metal in the engine. Have you even looked at the oil is it glittery?

X2 on finding another donor engine. This one sounds like a basketcase.
 
no the new spark plug is not bend just covered in sludge and obvious misfire going on in there
i'll check the oil tomorrow that.
Mainly funny how when the rpm increase the noise gets quieter until she sits at about idle at 800rpm and that when shes the loudest knock/chatter or wheni push the gas i hear more noise but when i let off the chatter slowly dies down.
 
You probably have multiple issues/sounds going on. You may still have a worn coupler on the SC.....which is where some of your noise is coming from. If you are getting oil soak that bad, that fast.....I would say it is not seal related. Myself and others can sit here and play the guessing game all night, but, on an issue where there are so many possibilities......and the fact we don't have the car in front of us....it is kind of pointless. You really should have it looked at.
 


Whitby-20131102-00763.jpgOk heres update from this morning checked all plugs and the other 5 are looking like they're brand new since replaced so that limits the issue to that front left cylinder.

I also drained and checked the oil and amazing there is no debris or metal shavings inside the oil or the filter at all, but i did notice only about 3 litres of oil came out which pretty much means 1 and a bit got thrown out the exhaust.

still waiting on the scan tool to come back from my brother. i'll also send some pics of the bad spark plug to see what you guys think.
 
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do compression test on that cylinder, if its low find a used engine.

if its the rod or piston thats knocking, find a used engine as well. replacing a piston dont always work out well. id think its a paper weight at this point.
 


matt5112 said:
Standard will have a bunch of L26s in stock for a good price.
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and Ya standard had the gt versions in scarborough but the only sc motor they had was in new york for $500 but has 312000km on it mines only got 225k so i might be just as bad swapping that one straight in there.

where you located matt? iam in the whitby area


what do you mean l26 is that the lower block number? do they use the same pistons? i thought the SC version would be higher compression pistons?
i thought i had the l67/l32 motor.

So scotty would you think a chipped piston would let oil right into the sparkplugs/ combustion chamber and if so would i need to machine the bore or sleeve it or would it just be a swap of the piston piston rings and rods? i know its just theroy until i get a compression test and pull codes but at least i could sleep better knowing that tonight lol

That could be causing the detonation. i hope so cause i hate to pull the motor if that was only the case.
 
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wild2crazy said:
So scotty would you think a chipped piston would let oil right into the sparkplugs/ combustion chamber and if so would i need to machine the bore or sleeve it or would it just be a swap of the piston piston rings and rods? i know its just theroy until i get a compression test and pull codes but at least i could sleep better knowing that tonight lol

That could be causing the detonation. i hope so cause i hate to pull the motor if that was only the case.
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if that piston is chipped toss that motor in the junk pick up a used engine swap it in there. the only way to rebuild these engines is to do so with lots of expensive machine shop work.


a used engine is the cheap way to go in the end. you'll spend way more rebuilding it vs a used engine.
 


wild2crazy said:
and Ya standard had the gt versions in scarborough but the only sc motor they had was in new york for $500 but has 312000km on it mines only got 225k so i might be just as bad swapping that one straight in there.

where you located matt? iam in the whitby area


what do you mean l26 is that the lower block number? do they use the same pistons? i thought the SC version would be higher compression pistons?
i thought i had the l67/l32 motor.

So scotty would you think a chipped piston would let oil right into the sparkplugs/ combustion chamber and if so would i need to machine the bore or sleeve it or would it just be a swap of the piston piston rings and rods? i know its just theroy until i get a compression test and pull codes but at least i could sleep better knowing that tonight lol

That could be causing the detonation. i hope so cause i hate to pull the motor if that was only the case.
Click to expand...

I'm in the Whitby/Oshawa area as well.

The NA engines have 9.x:1 CR pistons. SC is 8.5 I believe.

If you went with the higher comp short block, I'd suggest headers or a larger supercharger pulley.

Don't know if this link will work properly: http://car-part.com/cgi-bin/search....570945&userUID=0&userBroker=&userPage=1&iKey=

I'm not sure you can trust the mileage on engines from Abe's.

So the older supercharged engines are L67. low comp.

The older NA engines are L36s. Newer NA engines are L26s. Here are the L26s: http://car-part.com/cgi-bin/search.cgi?userSearch=int&userPID=1000&userLocation=Canada&userIMS=&userInterchange=A%3D%3DD&userSide=&userDate=2005&userDate2=2005&dbModel=61.11.1.1&userModel=Pontiac%20Grand%20Prix&dbPart=300.1&userPart=Engine&sessionID=200000000000000000634959350&userPreference=zip&userZip=L1R2A2&userLat=43.9103&userLong=-78.9311&userIntSelect=570952&userUID=0&userBroker=&userPage=1&iKey=

You'd need to change a few things over to run the aluminum pan, or just put your steel pan back on. You'd need to buy head gaskets, head bolts, LIM gasket set, valve cover gaskets, rocker bolts, coolant and oil/filter for two changes.

It's a lot of work, but you'd have a lower mileage short block. Worth it? Up to you. Hollywood wreckers might be worth checking out, reasonable price.

What you should do is get a scope in there and find out what the condition of the piston is.
 
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ok pulled some codes. p0134 02 sensor no detect
p0301 cylinder 1 misfire

now maybe cause my cat is full of engine oil maybe fowled the 02 i can see that happing but getting a knock like this from a bad 02 would be wierd.
anyways cyl 1 is getting the oil in it

so compression test coming in a couple of hours. Yay
 
WOW this car completely is impressing me everyday now.

Compression test the front 3 cylinders 1. ,3 , 5
here the readings

1cyl
dry 153psi
wet 175psi

3cyl
dry 160psi
wet 175psi

5cyl

dry 160
wet 178

now question i got is can i still have this type of compression and have something wrong with the lower part of motor or does this almost gaurentee its the heads? oh yeah 26000kms on motor which i think this is still producing alot of compression
 
you did say cylinder one piston and rod was replaced already right? if so junk that engine. its never gonna be right ever again.
 
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